TheRailwire
General Discussion => N and Z Scales => Topic started by: CNR5529 on August 25, 2017, 02:39:17 PM
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As most of you know, the Athearn Bombardier BiLevel commuter cars are great looking models, which suffer the same problem as most other coaches with inside bearing truck, such as Amfleets: they dont roll particularly well. A friend best described these cars as rolling marginally better than a sack of hammers. This topic has been previously discussed here https://www.therailwire.net/forum/index.php?topic=39533.msg483403#msg483403 (https://www.therailwire.net/forum/index.php?topic=39533.msg483403#msg483403), and a practical solution was presented for Amfleets here https://www.therailwire.net/forum/index.php?topic=39504.30 (https://www.therailwire.net/forum/index.php?topic=39504.30) using miniature bearings.
The inside bearing trucks as designed cause a lot of rolling resistance, and I believe this is caused by two factors: the internal friction of truck clips holding the wheelsets, and the truck mounted couplers and excessive lateral play of the wheelsets causing the back of the wheels to rub on the truck frames in curves. This means that longer trains such as those typical of transit authorities such as GO Transit, with up to 12 cars pulled by a single locomotive, are not practically possible in miniature.
Using the bushings proposed by @mmagliaro in the previous thread, as well as accurate reference material, I was able to redesign a truck from the ground up for 3D printing, to replace the original trucks.
[attachimg=1]
[attachimg=2]
[attachimg=3]
This conversion reuses the original wheelsets, and will require body mounted couplers as well as the bushings in question. Test prints have been ordered from Shapeways, and will be tested on a 7 car trainset once the conversion is complete. I hope to be able to report operational and aesthetic improvements in the near future!
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Interesting project!
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The key to decreasing rolling friction is the minimize the contact area between the axle and the bearing. Kato so far is the leader by using 1mm dia. steel axles and copper bearing plates with a very small contact area in the bearing.
Your design appears to use rather large diameter axles and bearings. I don't see how that will roll much better than the stock trucks. I think that using Kato wheels/bearings in your design would dramatically decrease the rolling friction. But if course that would be quite expensive.
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Very interested as well.
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@peteski Keep in mind that the stock athearn axle is 1.2 mm in diameter, vs the kato axle that is only marginally smaller at 1mm in diameter. What you see there as the "large axle" is the O.D. of the bushings, as well as the plastic tube used to isolate the two wheels and split axle. The actual axle is inside the bushings and tube.
Either way, testing will show if this is better or not than the stock truck. If it is, I'll make these available. If not, then no harm done trying to improve something that we can both agree is already a poor performer. :)
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This reminds me of similar problem I dealt with back in the 1990's when I built a detailed car-for-car replica of an Amtrak San Diegan I rode on when I was a member of the Belmont Shore Lines Model Railroad Club in San Pedro, CA.
All we had then was a choice of Model Power and Life-Like (my ultimate choice) F-40PH's and the Bachmann Amfleet 1 cars.
I rebuilt the F-40PH with an N-scale of Nevada replacement metal chassis and did some serious surgery to rebuild one Amfleet coach into a Food Service Cafe car and a second coach as a cab control car.
Finally, I had to do something about those horrible trucks. The rebuilt (and now heavier) locomotive could only move three cars on a straight and level track.
I ended up discarding the cars' wheels and axles and then cutting off the ends of the plastic truck frames. Next, I acquired a bunch of Micro-Trains "pizza cutter" wheel sets (I had plenty as I had been converting my entire fleet of cars to Micro's low-profile 1008 wheels.) Two reason for this: the Pizza Cutters had thinner and more true-running Delrin axles which minimized friction, and 2. the deeper flanges would help keep the cars on the rails during extended high-speed running in "push mode".
To hold the axles to the truck frames, I made short bearing boxes from precisely cut lengths of C-shaped styrene and cemented them to the ends of Bachmann's plastic central truck frame components while trapping a wheel set inside the bearing box. I had to make a simple alignment jig to ensure all the axles were parallel to each other as well as perfectly perpendicular to the bolster pin hole. NOTE: The cab control car didn't need any of this as it rides on conventional drop-equalizer outside bearing trucks.
The end result is a very smooth rolling eight car 1990's vintage Amtrak train that allows me to go up 2% grades with a single F-40PH, exactly as used on the prototype: five coaches (including one business class car), one food service cafe car, one cab control car, and one short baggage car with single centrally located doors on both sides which I semi-scratchbuilt using Con-Cor car body components as a starting point. The baggage car rides on conventional outside-bearing trucks like the cab car, so only a total of six cars use inside bearing trucks.
I ran this train in both push and pull modes many times as a member of the BSMRR club and still have the train today.
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@peteski Keep in mind that the stock athearn axle is 1.2 mm in diameter, vs the kato axle that is only marginally smaller at 1mm in diameter. What you see there as the "large axle" is the O.D. of the bushings, as well as the plastic tube used to isolate the two wheels and split axle. The actual axle is inside the bushings and tube.
Either way, testing will show if this is better or not than the stock truck. If it is, I'll make these available. If not, then no harm done trying to improve something that we can both agree is already a poor performer. :)
If you made the bushings (or whatever the axle is rotating in) about 0.5mm wide or less (instead of how wide they are now) that would decrease the contact area and the friction. I was thinking of etching the bearings out of thin (0.005") stainless steel or brass to minimize the contact area.
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Following!
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Hello all. I'm the person that brought this to Fredrick, and boy am I glad I did. First off the design is incredible and even if it rolls the same as the Athearn car, it will look wayyyy better so it's a win no matter what.
My train is seven cars so we'll be using it as a test bed. I plan to body mount 1015s.
I'll start by converting one car to the new trucks. I'll set up an incline with two identical lengths of track. Testing will simply be to set them both rolling down the incline and onto a flat. The car that rolls the farthest obviously had a lower coefficient of friction.
These are the bushings I ordered, and that Fredrick based the design on:
http://timesavers.com/i-9605176-13-bergeon-style-american-made-bronze-bushing-20-pack.html
I measure the axles on several trucks and found they were all around 1.2mm and so we settled on a 1.25mm bushing for a clearance fit. When they arrived I test fit them and they slipped right on.
They almost fit without modifying the axle tube as you can see here, compared to a Fox Valley wheelset:
(https://www.therailwire.net/forum/gallery/2/2507-250817225712.jpeg)
Once I knew they fit I used a precision Dairy Caliper to grip the bushing and roll the truck. It was extremely free rolling, albeit with no weight of any kind and being pushed by a giant hand.
(https://www.therailwire.net/forum/gallery/2/2507-250817230202.jpeg)
I'm really looking forward to further testing on these once they arrive.
Thanks again for your effort Fredrick. They look amazing.
Craig
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I'm very curious about the results.
I agree that the truck design looks very good, as you said, much better than the original trucks.
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The 1960s Minitrix F units had "bearings" made from brass tubes, about as simple as they could get, and the dummy versions actually rolled fairly well.
Knowing nothing about these cars, my biggest concern would be whether there is enough side play for the wheels, or the center tube, to rub on the sides of the bushing. If so, that would be a major source of friction, and could cancel any benefits from the better bearings.
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First off the design is incredible and even if it rolls the same as the Athearn car, it will look wayyyy better so it's a win no matter what.
Thanks! Indeed, accuracy of the truck was a big part of this exercise for me personally. It helps when one works with some of the guys that designed the original 1:1 truck... So far they are impressed with the CAD renders! Another requirement Craig and I agreed on early on was the need to develop lower rolling resistance using parts that are available to everyone. I cant design a truck, make it available through shapeways, and expect everyone who buys it to machine their own custom bushings, or etch brass pickup tabs like what Kato has done, its just not realistic. Many modelers/operators/collectors wouldn't have the equipment or the skillset to do this. That is why we settled on these tiny brass bronze bushings. Again, testing will either confirm any improvement or show that it was waste of my time. So far though, we both are confident that there will be an improvement.
Knowing nothing about these cars, my biggest concern would be whether there is enough side play for the wheels, or the center tube, to rub on the sides of the bushing. If so, that would be a major source of friction, and could cancel any benefits from the better bearings.
I completely agree with this, and will show you how we are addressing it in a minute. Part of the design philosophy here is maintaining tighter lateral play tolerances. I believe that a secondary source of the friction in the original truck was from excessive side to side "slop". As forces in the couplers made the truck pivot (particularly while curving), this slop caused one wheelset to move sideways to the left and the other to move sideways to the right, until both wheels were rubbing against the frame, and angling excessively. In railway vehicle dynamics jargon, we say that there is excessive angle of attack. By removing the truck mounted coupler, and ensuring that the wheels cannot touch the frame directly (only metal on metal contact with the side wall of the bushing), we hope to eliminate the second source of friction altogether. To ensure that there is no contact with the center tube, I designed an assembly jig to help modelers with wheelset refurbishment:
[attachimg=1]
First, trim the axle tube so that it fits between the mounting fingers (go/nogo). Next, mount the bushings on each stub axle, and press the stub axles on the axle tube. press until the wheels make contact with the outside of the jig mounting fingers. At this point, the wheels will be perfectly in gauge, and there will be enough built in clearance with the bushings and tube. :) As an added bonus, I included a drill template on the back of the jig to drill the new coupler mounting screw hole. This jig will be included with replacement truck sets.
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I am gunning to have two operating GO Transit L10 set-ups on my layout. There will be a helix with a 1.5% grade. Smooth rolling and all the extra weight I can add to a Kato MP36 will hopefully allow for it.
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Any thought for allowing electrical pickup? I am in the starting phase of putting LED lights in a cab-car of these units (headlight & flashing ditch, red rear class lights). I have the Streamlined Backshop Wheel Wiper kit for use with the standard trucks, but if these trucks pan out, would love to improve the overall performance.
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Any thought for allowing electrical pickup? I am in the starting phase of putting LED lights in a cab-car of these units (headlight & flashing ditch, red rear class lights). I have the Streamlined Backshop Wheel Wiper kit for use with the standard trucks, but if these trucks pan out, would love to improve the overall performance.
Pickups which rub against the wheel backs increase friction. But making the brass bushings/bearings into electrical pickups should do the trick without increasing friction.
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There are the bronze Bergeon bushings, right? Durability and pickup will be much better from those than with brass.
So, if I understand this correctly, the bushings will be mounted in the frame such that they cannot slide inward and touch the plastic axle tube? And the slight lateral play in the wheelset will be accomplished by letting the axle slide back in forth in the bushings, so the wheel backs can touch the outside faces of the bushings only (not the frame) and the bushings cannot move inward to touch the axle tube? If so, I completely agree that is the way to go. (And it's exactly how I designed my 0-6-0 engine project, by the way).
As long is there is just a hair of "play" or "float" of those bushings in the frame, they will happily fine a place to align themselves on that axle and it should roll smooth.
If you want to, you can lay one of those bushings flat on a piece of 400 grit sandpaper and swirl it around with your finger to sand it thinner. Peteski is correct in that the thinner you make that bearing, the less friction you will have.
A bushing bore of 1.25mm with an axle of 1.2mm leaves .002" of slop. That is a little high for a bearing, believe it or not, so they might be a little too sloppy in there. But time will tell.
This is a great project for so many reasons. Watching with great interest!
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Watching with interest as well!!!
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Any thought for allowing electrical pickup? I am in the starting phase of putting LED lights in a cab-car of these units (headlight & flashing ditch, red rear class lights). I have the Streamlined Backshop Wheel Wiper kit for use with the standard trucks, but if these trucks pan out, would love to improve the overall performance.
That was one of the reasons for leaving the bottom of the bushings exposed. I wont go too deep into the electrical design yet, as this is where @craigolio1, AKA the lighting package whisperer, really um... shines... But yeah, we figure pickup should be fairly simple to do should it be needed.
There are the bronze Bergeon bushings, right? Durability and pickup will be much better from those than with brass.
Yes, the bushings chosen are bronze, sorry about the confusion.
So, if I understand this correctly, the bushings will be mounted in the frame such that they cannot slide inward and touch the plastic axle tube? And the slight lateral play in the wheelset will be accomplished by letting the axle slide back in forth in the bushings, so the wheel backs can touch the outside faces of the bushings only (not the frame) and the bushings cannot move inward to touch the axle tube? If so, I completely agree that is the way to go. (And it's exactly how I designed my 0-6-0 engine project, by the way).
As long is there is just a hair of "play" or "float" of those bushings in the frame, they will happily fine a place to align themselves on that axle and it should roll smooth.
Exactly.
If you want to, you can lay one of those bushings flat on a piece of 400 grit sandpaper and swirl it around with your finger to sand it thinner. Peteski is correct in that the thinner you make that bearing, the less friction you will have.
I suppose there is nothing stopping us from doing this anyways in the future. I just made the truck frame that wide to prevent it from cracking, but the bushing itself could be thinner. You would just need to ensure that the bushings are seated slightly proud of the truck frame.
This is a great project for so many reasons. Watching with great interest!
Thanks! I am excited to see results (good or bad) when the new trucks come in!
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My idea for electrical pick up was to solder a magnet wire to the outside of each bushing, coming off perpendicularly. Once snapped in the frame the wire would be open to the exposed part at the bottom and won't affect fit or come any where near any moving parts. I'm going to mount my cab car wheelsets with Micro Trains king pins. The centre can be drilled out, all four magnet wires fed up through the centre, and the truck will swivel with out any issue. I'm in the process of installing a decoder in my cab car with the hope that I can reveal the completed working product shortly after the truck testing.
Apparently NEO Lube conducts and it was suggested that perhaps a bit of that in each bushing would improve the efficiency and promote conductivity.
And about the 1.25mm bushing on the 1.2mm axle. That was the closest size I could find and when I slipped it on it didn't feel to me that there was any play. Obviously my fingers are crude instruments for measuring those kinds of tolerances but I'm still optimistic. We're not dealing with a shaft spinning at 12,000 RPM hear. That said my experience with this stuff is very minimal.
I hope it works!
Craig
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My idea for electrical pick up was to solder a magnet wire to the outside of each bushing, coming off perpendicularly. Once snapped in the frame the wire would be open to the exposed part at the bottom and won't affect fit or come any where near any moving parts. I'm going to mount my cab car wheelsets with Micro Trains king pins. The centre can be drilled out, all four magnet wires fed up through the centre, and the truck will swivel with out any issue.
Apparently NEO Lube conducts and it was suggested that perhaps a bit of that in each bushing would improve the efficiency and promote conductivity.
Can magnet wire handle enough current for a decoder? I have always thought it was limited to max of between 20-30ma. Would your idea still be viable with decoder wire (36 awg)?
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My wire is 34awg. Totally different. Haha.
With four wheel pick up those 4 combined 34awg wires effectively create the equivalent of a 26awg conductor, which I think is plenty. I doubt the wires on my decoder are any bigger.
Also this may be carnival math, but current out can't really be too much more than current out and I'm going To be running 5 little LEDs with larger than normal resistors (I don't like my trains to have blinding lights.).
Maybe someone who knows for sure can chime in.
Edit: alternatively, instead of soldering, I could probably just pinch the wire between the bushing and the top of the seat when I install the bushing. The wires are so fine I doubt it would change the fit much, and every one would be the same.
Craig
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I'm so glad to see that upon revisiting the thread, electrical pickup has been addressed. :D
Can magnet wire handle enough current for a decoder? I have always thought it was limited to max of between 20-30ma. Would your idea still be viable with decoder wire (36 awg)?
With four wires to each rail that could handle roughly 3-4 times as many amps (allowing for intermittent contact at times). If you're just doing lights I can't imagine it would cause a problem. If you're doing sound as well... How many wants does a sound decoder draw if it's just horn and bell? Note that if you don't have a continuous use (i.e. no prime mover sound playing constantly) then the thermal load on the wire will be less.
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CNR5529: Looks good to me.
Peteski: I have long suspected that part of the reason Minitrix used their bushings was for better pickup. The zinc alloy(?) frame wasn't polished, and would have had about the same pickup quality as the early Atlas/Kato RS3s, which is to say, not the greatest. The bushings would have been much smoother, so make better contact with the axles, and stationary in the frame, so would at least have consistent contact there.
As for magnet wire, what are our motors wound with? It has to be able to handle the full motor current whenever the motor is running, and I can't imagine a passenger car decoder drawing more current than a working motor.
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Three words: Micro Roller Bearing.
The type used for the counterweight in automatic watches or something similar.
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In the Kato Amfleet thread someone was experimenting with tiny roller bearings. I think the same size or slightly larger than the bushings we chose here.
There were a couple of things that turned me off.
First they are wayyyy more expensive. I need 54 of them and I couldn't afford them.
Then, roller bearings don't from what I understand pick up electricity well especially if you lube them, so then you have to use wipers which adds more friction.
And finally, I was able to find bearings with 1mm bores but not 1.2mm. Doesn't mean they aren't out there. I just couldn't find them.
I'm sure there better, I'm just optimistic that the bushings will be good enough.
If someone can find a 3mm bearing with a 1.2mm bore then use it instead.
Craig
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1. Magnet wire comes in many thicknesses and is available as heavy as 12 AWG or heavier if that is what you need. :D So, you could get for example 28 or 26 AWG magnet wire. But I agree, for a function-only decoder driving few LEDs the total current will be fairly low.
2. Why is (insulated) magnet wire needed? The truck is made from a non-conductive material and the car is made from plastic. You can use bare conductors to pick up current from the bearings. Then bundle each side together at the top of the truck and solder to a flexible insulated stranded wire to route it inside the model. If you need thin bare wire just strip some stranded wire and then use the strands.
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Since the bearing isn't turning you wouldn't have to solder the wire to it. Use a piece of spring wire, such as phosphor bronze, and bend it so that each end presses against a bearing. Then solder the lead into the car to that, and you won't have to try to solder to the bearing without damaging the truck, or the bearing.
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Peteski,
I'm planning to use drilled out Micro Trains king pins to router the wires up into the car. Are you saying to use bare conductors, and then transition to an insulated conductor before all four come together in the kingpin?
Nkalanga, that's a good idea as well.
Does anyone know what, if any, risk there is to soldering directly to the bushing? Deformation perhaps?
Craig
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Test trucks were ordered on Friday, and I just got notice that they are shipping out today. That is probably the quickest turnaround I have experienced yet. Awesome!
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Peteski,
I'm planning to use drilled out Micro Trains king pins to router the wires up into the car. Are you saying to use bare conductors, and then transition to an insulated conductor before all four come together in the kingpin?
Nkalanga, that's a good idea as well.
Does anyone know what, if any, risk there is to soldering directly to the bushing? Deformation perhaps?
Craig
Exactly. Bare wires within the truck assembly and then thin flexible insulated stranded wore up into the kingpin. Something like TCS decoder wire (I fund it more flexible and easier to solder than Digitrax wire). Or ESU also sells excellent decoder wire.
I would not worry about deforming the bushings by soldering anything to them. And I do like solid soldered connections. Do you know if those bushings are brass, bronze, or sintered brass or bronze?
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I doubt that soldering to the bearings would damage them. My concerns were heat damage to the frame, if the soldering was done after the bearing was installed, or the bearing being forced out of alignment if the wires didn't sit exactly right. Very fine wire probably wouldn't exert enough force to twist a bearing, but if it wasn't rigidly attached, even that small chance would be eliminated.
Plus, by not soldering, assembly, and disassembly if needed, would be that much easier.
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Peteski, the description says bronze.
Nkalanga, the plan was to solder the wire to the bushings prior to installation. The magnet wire is so thin I just can't see it putting enough strain on the bushing to move it out of alignment, but that is something I hadn't thought of and it makes me want to use the thinnest wire possible for sure. I agree about the ease of service without the wire being permanently attached to the bushing. Thats something to consider for sure.
Craig.
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There's a flaw in your current measurements. You cannot assume that just because you have 4 wheels on the track, each with a magnet wire to its bearing, that you can conduct 4x the capacity of the magnet wire.
There will be moments when only one of those wheels is actually conducting, and during those times, all the current will flow through one magnet wire.
So you need to design this so that each individual magnet wire can handle the total current.
#34 magnet wire is only rated at 56 mA
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There's a flaw in your current measurements. You cannot assume that just because you have 4 wheels on the track, each with a magnet wire to its bearing, that you can conduct 4x the capacity of the magnet wire.
There will be moments when only one of those wheels is actually conducting, and during those times, all the current will flow through one magnet wire.
So you need to design this so that each individual magnet wire can handle the total current.
#34 magnet wire is only rated at 56 mA
While I agree with your assessment, IMO for very short runs the wire can carry much greater current. It is all about the resistance.
Resistance of 34AWG copper wire is 0.261ohms per foot. The wire leads in the trucks will probably be less than 1" in length (before they are bundled together and soldered to a thicker feeder wire. So 0.216/12=0.018 ohms per inch. From that you can calculate a voltage drop and power dissipation with a known current. I'm not going to calculate the voltage drop or power dissipation for higher current. It's fusing current for duration of 10 seconds is 5 Amps. So I think it is quite safe to use 34AWG wire in this application.
My info came from "Tables of AWG wire sizes" section of https://en.wikipedia.org/wiki/American_wire_gauge (https://en.wikipedia.org/wiki/American_wire_gauge)
Craig, so the bushings are bronze. It also solders well. If it is sintered bronze, some of the solder might soak into the microscopic voids in the metal, but I don't think that will affect bushing's functionality. But if it is already impregnated with lubricant, it might be difficult to solder.
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I won't try to use lube to impregnate the bushings until after I solder. I hope someone hasn't already impregnated my bushings.
Craig.
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I hope someone hasn't already impregnated my bushings.
That just sounds strange. :)
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Haha. I know. I couldn't resist. Sorry.
Anyway. I have some extra bushings so I think I will solder one to see how that goes. I've taken apart enough of my projects because something isn't working (actually working on an Atlas loco right now that is about to have motor leads soldered to the motor tabs because it stopped working). I'm a big fan of trying make it so that I never have to get back into it and like to solder what ever is practical.
Craig
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I'm a big fan of trying make it so that I never have to get back into it and like to solder what ever is practical.
Craig
You and me both! Except when it comes to the wiring between the shell and chassis. I like to be able to remove the shell without having an umbilical cord connected to the chassis. :)
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:D
[attachimg=1]
[attachimg=2]
So the trucks finally made it across the border, and already got their 24 hr bestine soak. Now I will procede do defuzz the prints before handing them off to Craig for testing with the bushings. We will soon know if this endeavor was worth while!
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Watching patiently. This might get me to by so GO Transits.
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While I agree with your assessment, IMO for very short runs the wire can carry much greater current. It is all about the resistance.
Resistance of 34AWG copper wire is 0.261ohms per foot. The wire leads in the trucks will probably be less than 1" in length (before they are bundled together and soldered to a thicker feeder wire. So 0.216/12=0.018 ohms per inch. From that you can calculate a voltage drop and power dissipation with a known current. I'm not going to calculate the voltage drop or power dissipation for higher current. It's fusing current for duration of 10 seconds is 5 Amps. So I think it is quite safe to use 34AWG wire in this application.
My info came from "Tables of AWG wire sizes" section of https://en.wikipedia.org/wiki/American_wire_gauge (https://en.wikipedia.org/wiki/American_wire_gauge)
....
Peteski, your calculations about how much current a short length can carry are correct. I am more worried about how hot that little filament-sized wire will get, even if it doesn't "fuse" (burn through) in a short-circuit condition. 5A (typical booster limit) through that length at that resistance works out to about 1/2 watt of power. That's a lot of heat for that little wire to dissipate.
I agree that it will support the required current if nothing goes wrong. I'm still a little worried about what happens when something does go wrong. I guess my only advice would be to try to make sure that wire doesn't touch anything plastic.
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Peteski, your calculations about how much current a short length can carry are correct. I am more worried about how hot that little filament-sized wire will get, even if it doesn't "fuse" (burn through) in a short-circuit condition. 5A (typical booster limit) through that length at that resistance works out to about 1/2 watt of power. That's a lot of heat for that little wire to dissipate.
I agree that it will support the required current if nothing goes wrong. I'm still a little worried about what happens when something does go wrong. I guess my only advice would be to try to make sure that wire doesn't touch anything plastic.
You are correct of course. It would be prudent to use heavier gauge wire of possible.
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Why not add a small slit for 010 PB wire to be visible in the snap pocket and when the bearing is snapped in it will make contact with the PB wire (and maintain that contact). The pocket would need a groove for the wire to deflect into so the bearing will still fully seat. The wire would exit out the top or bottom of the truck and could have grooves to glue it in place to hide it and then it bends up like a truck tab piercing a small hole in the bottom of the car where a connector could be added or a wire soldered to that. Red below is the wire.
________ ________
| \ || || / |
| \|| ||/ |
| |\_____________________________/| |
O
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:D
(Attachment Link)
(Attachment Link)
So the trucks finally made it across the border, and already got their 24 hr bestine soak. Now I will procede do defuzz the prints before handing them off to Craig for testing with the bushings. We will soon know if this endeavor was worth while!
Awesome work! Looking forward to phase 2.
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Why not add a small slit for 010 PB wire to be visible in the snap pocket and when the bearing is snapped in it will make contact with the PB wire (and maintain that contact). The pocket would need a groove for the wire to deflect into so the bearing will still fully seat. The wire would exit out the top or bottom of the truck and could have grooves to glue it in place to hide it and then it bends up like a truck tab piercing a small hole in the bottom of the car where a connector could be added or a wire soldered to that. Red below is the wire.
Why of course! I like it!
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@Lemosteam I like that idea! We'll see how initial tests fair, but that would be pretty easy to implement going forward.
Also, while waiting to meet up with Craig, I got some paint down.
[attachimg=1]
And a side by side with stock trucks:
[attachimg=2]
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Looks good. Too bad you didn't show a side by side comparison of the truck's sides. The top view doesn't seem all that exciting.
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If a side view is what you want, then just ask! :)
[attachimg=1]
To be honnest, I didn't post this view earlier because I find the detail didn't pop as well as the closeup did. Stuff like the longitudinal dampers, traction rods, casting core holes, tread and disc brake units and some of the more hidden details like the elastomeric sidebearers are hard to see in the photographs. The real point of the top view though is to show that the bolster is the proprer width. To me a major flaw in the looks of the Athearn truck is that all the secondary suspension components are flush with the wheels (the truck is too narrow). The top view illustrates how this truck looks more appropriate. Consider this photo of the West coast express BiLevel truck.
http://www.canadianrailwayobservations.com/RESTRICTED/2016/October2016/via.htm (http://www.canadianrailwayobservations.com/RESTRICTED/2016/October2016/via.htm) scoll down a bit.
Also for full disclosure on prototypical accuracy, I did not include the lateral rods and dampers as they would have interfered with the truck rotation...
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Thanks - they look good from the side too.
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Thanks! Only one thing left to test...
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One thing indeed.
The bushings came in the mail a while back and I haven't lost them.
I have my drill press all ready to go.
The decoders in the loco and cab car should be done tomorrow.
I'm picking up my MT True Scale couplers on my way home after I pick up the trucks from you.
I'm hoping to post a video of a simple test of two cars, one equipped with the new trucks, and the other stock, rolling down a pair of inclined tracks, on Monday night.
Following that I'll work on the rest of the fleet and then we'll get some footage of a train, hopefully being pulled effortlessly by one loco. I only have seven cars but I understand three or four are about the limit as they are now.
Craig
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Well, I can now confirm two things:
- Conversion is literally a snap! The bushings snap nicely in their seats, with just enough pressure to hold them firmly from moving, but not so much that the FXD frame would be at risk of cracking. Using the assembly jig made quick work of prepping the wheelsets.
- Even with just one truck converted, with no time spent optimizing the bushing positioning and no use of any lubricant, there is a noted reduction in rolling resistance.
The rest of the trucks have been handed off to Craig for installation in his test consist, so he will be able to report back soon with more objective findings. Until then, here are more progress photos.
[attachimg=1]
[attachimg=2]
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Now I am starting to get excited. After not being able to pull 6 cars up a slight grade, I put my cab conversion on hold, awaiting these results.
Any estimates on costs for these new trucks and bushings?
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This is making me regret selling my Sounder consist I had, Since that was one of the reasons I sold it....
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Any estimates on costs for these new trucks and bushings?
Cant say just yet what the final price will be, because there may be a few alterations to the CAD model based on our testing, which would change the price a bit (so far there is one minor change to address). That said, there will be some savings for both the bushings and the trucks when purchasing in larger quantities. The bushings are 4-5$ per 20 pack (8 needed per car) depending on how many packages you order, and the trucks are in the neighborhood of 4-6$ per truck IIRC. That will include the wheelset assembly/drill jig as well. Once we are done with the testing and modifications (and the project is actually deemed successful), I will be able to formally release these at Shapeways.
Thanks for the interest!
This is making me regret selling my Sounder consist I had, Since that was one of the reasons I sold it....
Too bad, Sounder is one of the more stylish BiLevel paint jobs...
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Those look great!
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I was able to get a six car consist converted last night. I still have 1 car left but it will require modification in order to run the wires through the kingpin for power pick up.
The result. It definitely rolls better that the original. Not nearly as much as I had hoped. I have a video but can't figure out how to post it. What it shows is two parallel 6 foot runs of flex track. One end is elevated about 4" and gradually slopes down so that second piece of track is flat.
When the two cars are released at the same time, the car with bushings accelerates faster and rolls farther making it right to the end of the 6 ft run. The original car fell short about two car lengths.
So it's no Microtrains truck. But it's an improvement for sure. You can really feel the difference when pushing the cars with a finger. The original feels like all its brakes are stuck on. The new one feels like half its brakes are stuck, haha.
I tried lubricating one set of bushings with graphite spray. It may have made a little difference but I didn't have the chance to properly test it. I'm also going to try some ceramic wax I have for my triathlon bike chain.
http://www.finishlineusa.com/products/chain-lubricants/ceramic-wax-lube
The biggest thing with the trucks are assembly. You really have to make sure that everything is in there just right otherwise something might rub. The disc brake hanger for example, I unknowingly bent it in on one truck and it actually works like a brake! Amazing. And not good!
All and all I'm still optimistic but I thought results would be better. The real proof will be when I can test the train on a layout in a few weeks time.
I'll post more after I can experiment with lube.
Craig
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The results are what I expected. :| I mentioned making the bearing sleeves narrower to decrease the contact area (and friction) between the bearing and the axle. If the bearings were made very thin that would be ideal.
Do you happen to own one of the Kato Amfleet cars (or a pair of the Amfleet trucks)? It would be interesting to see how your design compares to the Amfleet truck design.
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I mentioned making the bearing sleeves narrower to decrease the contact area (and friction) between the bearing and the axle. If the bearings were made very thin that would be ideal.
So when Craig picked up the trucks for testing, he left some spare bushings to experiment with. I was able to test the effect of adding different types of lubricants, and ended the night by carefully cutting the bushings in half with a wire saw to test the effect of reduced surface area, as you had previously mentioned. The bushings are now roughly 1/3rd of their original thickness (0.5mm / .020"), but this only marginally increased the distance traveled compared to the full width bushing. It was way tougher to ensure proper alignment, and in the end provided very little reward.
[attachimg=1]
The results are what I expected. :|
The car does roll better than a stock Athearn car and looks better too, so all in all it is a step in the right direction. :) That said, there is still room for improvement. I do have another idea I want to try (inline with what @Loren Perry described on page 1), but it is going to take a bit of time to get it worked out. Craig also has some interesting lubricants that might help, so I am looking forward to the next round of experiments.
If it was an easy problem to solve, someone would have already solved it! :D
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Thanks for this info. So, one possible modification to the design has been verified as a solution with diminishing returns. I'm still curious how your trucks compare to the Kato Amfleet trucks which to me are as close to the ideal design as possible (thin axles and narrow bearings). But Kato also puts a dab of grease in each bearing - I'm not sure if that really makes things better.
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What about using neolube?
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I did try neolube, but it didnt help in this case. We tried some better graphite lube and it made things better, but I'll let Craig speak to that.
Pete, I dont have any Amfleet cars, so can't compare. But stand by, I have a solution in mind that will very much reduce the contact surface area, and that people will still be able to do at home with minimal effort.
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Neither Fredrick nor I have those trucks on hand. If anyone has one they would be willing to disassemble and document please feel free to post the results.
Keep in mind while this isn't a holy cow result it's by no means a failure. I'm still looking forward to seeing how many cars my F59 can pull as there was improvement.
My goal here isn't to get a magic carpet. It's to get a train that moves. This isn't the subject of the post but while installing the decoder I've noticed there is room in the loco for some weight so I'm looking at some options there. Combining the two may result in a much better train.
Craig
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Neither Fredrick nor I have those trucks on hand. If anyone has one they would be willing to disassemble and document please feel free to post the results.
I have these Karo trucks (and cars) and I have even posted some truck photos (it might have been back on the A-board). What I was asking for is not to see the truck's construction (I know it well) but how the those truck's rolling characteristics compare to your trucks. It would be good to see how the Kato Amfleet compares when rolled down the same slope you tried your cars on.
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Indeed. I see what you mean now.
How about this. You weigh your Amfleet car and I'll weigh mine. I'll send you the parameters of my ramp which will be very easy for you to duplicate. We match up the weights and perform the same test and compare how far the cars roll. Do maybe three tests and average the results.
Would you be willing to do this?
Craig
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Indeed. I see what you mean now.
How about this. You weigh your Amfleet car and I'll weigh mine. I'll send you the parameters of my ramp which will be very easy for you to duplicate. We match up the weights and perform the same test and compare how far the cars roll. Do maybe three tests and average the results.
Would you be willing to do this?
Craig
That sounds reasonable but with the amount of projects waiting to be completed (and lack of space for a decent length ramp) I will decline the challenge (at least for now). But I am curious about the results. Do you possibly know any modelers around your area (or in your country :) ) who own Kato Amfleet cars? Maybe they could lend you one for testing? I'll be even willing to go as far as reimbursing you for buying one Amfleet car on your next model train order. That way you could own one for testing and for evaluating the truck's construction. :)
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Ok. So conceptually the idea here is to reduce the amount of surface contact for friction reduction. Been mulling this...
I have a couple thoughts on this.
Metal rides well against FUD/FXD. Not as slippery as delrin, but hard like metal on glass.
What if you designed the snaps back down to the axle diameter +0.3 mm on the radius. Then to keep the axle centered you added a cone around the OD of the snap radius with a small, like 0.3mm wide, flat on top with that flat having about 0.7mm gap to the back of the wheel on each side. This would allow 1.4mm of lateral side play.
(https://www.therailwire.net/forum/gallery/2/2711-150917140431.jpeg) (https://www.therailwire.net/forum/index.php?action=gallery;sa=view&id=2308)
When the wheel does make contact, iut will only be on one side and the surface area is minimized to the 0.3mm flat on top of the cone. The axle shaft would have only a line contact at the top of the axle to the ID of the snap pocket for the length that the sideframe there is thick.
Note- all printing artifacts would have to be cleaned from the snap pockets.
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Tossing another idea into the ring - micro ball bearings have fascinated me since I was disassembling servo motor gearheads back in the '60s. Here's a supplier (https://www.lily-bearing.com/ball-bearings/miniature-bearing/miniature-metric-bearings/) of super-miniature ball bearings. Have no idea of cost, but if you want a truly free-rolling solution, here you go.
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@Lemosteam, I have an idea that incorporates some of the elements that you described. However I believe I can further reduce the contact area. That said, I am waiting for the final test on if Craig's loco can haul all the modified cars before starting revision 2. I believe he is almost done with the conversions. My second idea also gets rid of the bushings, in favour of materials most of us have on hand. The lateral boss is also part of that plan.
@C855B we did look into this, but enough bearings for an 8 car train was close to 700$... :(
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Tossing another idea into the ring - micro ball bearings have fascinated me since I was disassembling servo motor gearheads back in the '60s. Here's a supplier (https://www.lily-bearing.com/ball-bearings/miniature-bearing/miniature-metric-bearings/) of super-miniature ball bearings. Have no idea of cost, but if you want a truly free-rolling solution, here you go.
IIRC @mmagliaro experimented with using (inexpensive) micro ball bearings in his scratchbuilt loco but abandoned that idea. One of the problems was very poor electrical conductivity. Yes, you can install wheel wipers but that increases friction . . .
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In looking around I was able to get that down to $15 an axle (http://www.vxb.com/SMR681-Bore-Dia-1mm-Outside-3mm-Width-1mm-p/smr681.htm), but... yeah, I see what you mean. Too bad.
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I have finished the conversions. It took some time to sort out how to get wires run to the powered trucks on the cab car but I solved that last night. I need to revisit the alignment of the bushings as some cars roll very well and others not so much. Just need to find some time that's not at 0300 in the morning. I have less patience then. Haha.
I'll post photos soon.
Craig.
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I tried using a drilled out MT king pin to attach the trucks but drilling out the truck frame damaged it so I needed a way to do it with out modifying the truck. I found some styrene tube that fit the hole in the truck perfectly. I flared the end with heat to create a flange and then filed under the flange a little so that once installed, the truck could rock.
Then I drilled out the frame. The rod was a tight friction fit but I still wanted to have a locking device so I found a larger styrene tube and sliced through the side, creating a clamp that slides on from inside the car. I beveled the end of the tube to make it easier to slip the clamp on.
34awg wires fit through no problem. Larger wires would too.
(https://www.therailwire.net/forum/gallery/2/2507-150917195004.jpeg)
I soldered the wires onto the bushings prior to assembly and then built the trucks, inserted the tubes and fed the wires through.
(https://www.therailwire.net/forum/gallery/2/2507-150917195157.jpeg)
(https://www.therailwire.net/forum/gallery/2/2507-150917195435.jpeg)
Once the trucks were mounted on the frame I slipped the clamps on over the ends and it was done. Between the friction of the tube in the frame and the clamp they are held in very strongly.
At the end in the photo I've removed seating to make room for electronics. At the other end I made the tube long enough that the clamp sits just above the seats.
I'll probably put some kapton tape under the trucks to keep the wires flat. But you can't see them as is unless you really get down and look.
Craig
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This weekend is the Brampton Model Railway show (now also known as the Greater Toronto Trainshow). Craig and I will be conducting tests with his newly retrofitted BiLevel consist on 300+ ft of the Ntrak Roadshow layout. If any Railwire members are in the Toronto area this weekend, come by and say hi!
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Well it wasn't the success I'd hoped it would be, but I would still call the experiment a success because we improved on the performance of the original design. I think there's more that can be done but we're headed in the right direction.
This link shows my seven car trainset on the N-Trak Roadshow's layout at the Brampton train show (thanks guys for inviting me. I had a great time and enjoyed meeting all of you!).
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Modifications:
The cab car has a TCS function decoder wired for track pick up via 34awg magnet wire to each of the 8 bushings. The loco had a Digitrax decoder. Aside from the decoders and the addition of LED lighting, I also upgraded the entire trainset to Microtrains True Scale long shank couplers. The couplers have whiskers trimmed to allow the freedom to swing side to side in the draft gear, and the two coupler halves are fused together since the whiskers are no longer there to keep them together. I did this because the couplers are very stiff in the boxes and I was afraid it would cause the cars to push outward in the turns and put additional pressure on the trucks. Finally, I moved the couplers in a little to allow for closer coupling. These couplers don't have a slinky effect and can there for be closer together and work more reliably in pushing mode.
Observations related to the modified train's performance:
We started with a train of 8 modified cars. Fredrick has one too. It pulled no problem for the most part but did struggle a little through some of the sections of the layout. Then we added a single Unmodified car and that brought things to a halt. Literally. It was slow on a straight and then stalled in the first curve. Fredrick made a good point in that the addition of that one car was like adding another four modified cars. We removed the unmodified car, and Fredrick's modified car so that just my 7 car set was running. The train ran fine with no problems related to the trucks. I wish I'd filmed it but the highlight was watching the train negotiate snaking through a three track cross over from the inside most to the outside most track.
Observations not related to the performance of the trucks... and struggles.
Even though Fredrick carefully calculated where I should mount the couplers, with my ham hands (and I think might need glasses) I mounted the couplers so that some of the cars were too close together, and the diaphragms fouled in some of the turns. This caused the train to slow or derail. Moving from the inside track to the outside track helped this.
Due to some issues with connector tracks on the N-Trak modules I had some uncoupling issues. This was brutal as due to my modifications and the close coupling, it was a real test of patience to couple these cars.
I'll be switching the train to 1015s, at least until testing is complete, as the True Scale couplers are just complicating things.
The decoder in the cab car needs keep alive capacitors big time, but, the power pick up experiment was a success.
Conclusion:
Good:
We basically doubled the useable train length.
Non friction adding power pick up proof of concept was a success. And my cars didn't catch fire or melt..... yet.
Bad:
We wanted to get to 10 cars so the GO transit guys can be happy too. I would say the reliable limit is 7.
Assembly needs to be done PRECISELY. A deviation as little as a few .001" has a noticeable effect on the rolling capabilities and tuning is difficult once assembled as it's hard to move the bushings around once clamped in.
Recommended improvements:
Fredrick made a kick a$$ assembly fixture. It made assembling the wheel sets in gauge very easy and quick. The issue is getting the bushing to seat in the best spot when snapping them in. This is where I spent literally HOURS messing with the bushings. I feel like a set of shims could help here, or possibly an improved version of the truck could include a slot for the bushing to seat in so it self located the same way every time.
That's it for now.
Fredrick, @CNR5529, you did an absolutely outstanding job on the truck. It looks 1000 times better and performs 100% better. Hopefully we can find a way to make that 200% better.
Craig
PS: Fredrick I'm still pissed off that my Dinner Train was a complete fail so if you feel I've embellished at all in an effort to have SOME success from the day please add any corrections. Folks Fredrick has no feelings. Only computations and hypothesis.
PPS: That was supposed to be a joke either in case Fredrick has feelings and is insulted, or in case I'm right, and he had to be told it was a joke.
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Well it wasn't the success I'd hoped it would be, but I would still call the experiment a success because we improved on the performance of the original design....
Craig
PS: Fredrick I'm still pissed off that my Dinner Train was a complete fail so if you feel I've embellished at all in an effort to have SOME success from the day please add any corrections. Folks Fredrick has no feelings. Only computations and hypothesis.
PPS: That was supposed to be a joke either in case Fredrick has feelings and is insulted, or in case I'm right, and he had to be told it was a joke.
These kick-a$$-in-the-head moments are often ROFLMAO ones too... glad you pro's know what you're doing !
BTW, my first ever Rapido souvenir (CBQ) Baggage car will roll onto a Kato CZ as a 'replacement' car at some stage.
Hope to try more in future,
regds Dave
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or in case I'm right, and he had to be told it was a joke.
Noted...
LOL, the results of my analysis match your findings. The new trucks are an improvement over the stock arrangement as we were able to pull a 7-8 car train. (And boy was I pleased to see that train start to roll!) However the coupler/diaphragm problem caused binding on some curves which stalled the trainset. That and the true scale couplers were infuriating to couple without the centering!!! I also agree on the keep alive caps.
Bottom line, this is a partial success. I think grades would have been problematic, and there is still room for improvement. Stay tuned for Rev. 2.
P.s. I was so focused on programing the ditch lights on your loco and cab car, I never even saw the whole diner train on the track! :facepalm:
P.p.s Pics or it didnt happen. :trollface:
glad you pro's know what you're doing !
It only looks like we know what we are doing... HAHAHA. To be fair, and I've said this before, if this was an easy problem to solve, someone would have solved it already. So yeah, a bit of engineering and a bit of experimenting is going on here.
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IIRC @mmagliaro experimented with using (inexpensive) micro ball bearings in his scratchbuilt loco but abandoned that idea. One of the problems was very poor electrical conductivity. Yes, you can install wheel wipers but that increases friction . . .
Exactly correct. Not only that, but the decrease in friction from using miniature ball bearings vs a thin steel axle in a bronze bushing is not very guaranteed. Those little 681 and 681x bearings don't roll as smoothly as you'd think. Where they might shine over a bushing would be with heavy loads, but that isn't the case here with a little N Scale car to carry.
A thought on getting the bushings located exactly right so they are both centered on a given axle... Yes, this is an absolute must. And if they are mounted in a rigid way, I don't think you can ever make it work. They have to float just a little so that the axle can find its happy place going through the two bushings. My experience with this from my 0-6-0 mirrors yours with regard to a misalignment of only .001" being "huge". I have an idler gear running in two of those bushings. I found that the only way to make it work so that the gear axle would spin freely in the bushings was to put the bushings into their holders, put an axle through them, clamp everything down, while repeatedly spinning the axle with my fingers to make sure it was free
when I got the clamps right. THEN solder the bushings in place so the wouldn't move. And yes, an error of only .001" or so would make the axle bind up badly. There is not a lot of slop in those bronze bushings (which is as it should be).
My case was with a gear, so I couldn't allow any slop in the bushings. But for wheels in a truck, you certainly can.
Perhaps reaming out the insides of the bearings just a hair would make the whole thing very tolerant of any slight misalignment when assembling them. They make 1.55mm chucking reamers. http://www.northbaycuttingtools.com/0610-155mm-hss-chucking-reamer-53300610 (http://www.northbaycuttingtools.com/0610-155mm-hss-chucking-reamer-53300610)
You could spin one of those through the bearing to open it up from 1.5 to 1.55 (that's only .002"). But the assembly tolerance and rolling quality would improve.
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A few weeks ago, @peteski asked about how the Athearn inner rolling bearings fare against the Kato Amfleet bearings (and, also, these new ones, which are still a work in progress). So, I decided to give it a test myself. I strung together 23 of the Kato Unitrack 248mm (9.75") straights. I created an ~8% launching ramp (4.5" in first 55") and then a long straight track (which scared the heck out of the cats).
The launch point
[attachimg=1]
[attachimg=2]
Looking back from end to launch
[attachimg=3]
I tested not only the AmFleet and Athearn Bombardier, but a number of other cars, too. You can see that I had a number of Kato passenger cars that ran into the bumper at the end of the 23 sections of track. The Kato CalTrain coach 3860 hit the bumper at speed, while most of the others were already slowed down.
While the Kato Amfleet cars did better than the Athearn Bombardier, neither do very well compared to the others.
[attachimg=4]
Also, here are a couple videos of the testing. First the Athearn Bombardier
And a Kato Bi-Level Cal Train car
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Great info Rick - thanks for setting up this experiment! You could have most likely got valid info from a much shorter track with gentler incline but you went al out with a huge ramp and long coasting truck - I like it! :D
What is not surprising is that all of the 2-axle outside-bearing (axle-point/bearing cup) trucks had much less rolling resistance than any inside-bearing trucks. Those trucks have very low rolling resistance.
One thing which is skewing the results is the mass of those cars. The heavier cars will have more momentum. The ideal test would be to run each pair of trucks under the same car test body. Or I suppose the mass coudl be used alongside of the rolling test results to nullify the effect of the car's mass. We would need one of our resident math experts to come up with a formula to do that (and we would need to know the weight of each car).
For example I wonder if the Athearn Caltrain cab car has a different mass than the coaches? That could explain the difference between these cars (even though they use identical trucks).
I'm also surprised by the difference between Kato Amfleet Cafe and Coach. They weight just about the same and use identical trucks. Is is possible that one of them has more running time (more broken in) than the other? Kato greases the Amfleet trucks with small globs of grease in each bearing - maybe if the grease is thoroughtly spread into the bearing changes its rolling resistance?
What is missing from this test (and what I was hoping for) was a comparison between the Kato Amfleet and those custom built Athearn inside-bearing trucks we are discussing here. But I realize that you had no way to test that truck.
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Agghh, I had meant to weigh the cars, but when my wife got home, I got distracted in cleaning up my experiment. I no longer have access to good lab scales, so will have to use a kitchen scale. May not be sensitive enough.
Both Amfleet cars are brand new, delivered today. I also order a pair of replacement Kato trucks, so I can check if they make a difference.
I went for the steeper slope after I couldn't even get the Athearn cars to roll down the full length of a 1.5% grade on the JACALAR. Then I just kept lengthening the coasting track for the cars, until I ran out of easily accessible straight Unitrack, so that most cars didn't reach the bumper.
I had fun :-)
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Love it! Thanks for sharing your results. We should be able to duplicate the ramp to compare any mods here as we carry forward. I should also be able to duplicate the unmodded result as a control...
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Besides mass(weight), I might try rerunning part of the test, to measure the exit velocity from the ramp. With mass, initial velocity and distance, we can calculate friction. Granted, it will be in scale-mph, but converting is easy.
The videos show how much slower the Athearns are vs the regular truck Katos on exit of the ramp.
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In theory, the mass wouldn't affect the exit velocity from the ramp, Galileo proved that. It would affect the momentum, and thus the roll-out distance. In practice, it would also affect the exit velocity, because it would affect the friction in the trucks.
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OK, a little more data on my experiment (just wish I could test the new trucks). I found a really cool little electronic balance, for all of $12 on Amazon. 0-500g range (approx 1 lb) with 0.01g readout. Seems to be fairly accurate with high precision (repeat ability). I measured the mass (weight) of each of the cars, and also the velocity of the car, using my Accutrack II speedometer, at the point the car hits the bottom of the ramp, and starts across the flat. This is the point where there is no additional acceleration due to gravity.
I also converted units into metric, for anyone interested in doing further calculations. Distance traveled is from the first experiment, but the cars were all behaving the same for this retest.
It is interesting to note that in addition to the inside roller bearings, the Athearn cars are significantly heavier.
[attachimg=1]
Items of note:
(1) on the Amfleet Cafe, I tried replacing the trucks with the spare pair I ordered from Kato. Car would barely move (and yes, I checked for everything I could think of). When I replaced the originals, it actually rolled a bit better (exit velocity was measured prior to my playing with trucks)
(2) When I added the decoder and extra lighting to the Kato Cab Car, I also added extra weight, hence the difference between 4024 and 3860
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So its been a few weeks since last checking in with the somewhat improved BiLevel trucks, and I spoke of a version 2.0. Got a bit swamped with the day job, as well as other projects, but here is what I have been working on so far.
The idea was to do away with the bushings and associated misalignment issues, reduce contact area thus reducing friction, and generally simplify assembly. In this case, the truck frame has a series of holes pre-drilled in specific locations.
[attachimg=1]
These holes will allow for thin brass/steel/material of choice wire to be installed and act as very small load bearing surfaces. The horizontal wires will provide single point contact on the top of the axles, while the vertical wires have 0.0005" clearance (0.001" total clearance) for longitudinal play. Only one vertical wire should make contact with the axle at a time at each axlebox. The total contact area for the entire car is now reduced to 16 single points of contact (ok ok, not really if you consider actual hertzian contact theory, but we are talking microscopic contact areas), and I see no way to get less. Slight misalignment should not be problematic, as the wheelsets would still only make single point contact on each wire.
[attachimg=2]
[attachimg=3]
[attachimg=4]
[attachimg=5]
[attachimg=6]
The idea will be to simply glue the wires in place, trim to length, install wheelsets, and off you go. I still need to put in an upstop/wheelset retention method, which might just be a retention wire under the axle or a bit of a plastic protrusion to snap the wheelset in. I will also add the lateral bosses similar to what @Lemosteam had sketched out previously. After that, these will go to the printers for testing!
At this point I anticipate that electrical pick up will be completely unreliable, so the bushing trucks might still be necessary for electrified cab cars, but we will see during the next round of testing.
Oh, and just for clarification @peteski, I hid the plastic axle tubes in these screenshots to make it easier to see, but they still hold the wheelset spacing as before. :D
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Oh, and just for clarification @peteski, I hid the plastic axle tubes in these screenshots to make it easier to see, but they still hold the wheelset spacing as before. :D
Oh come on - I'm not that bad! :D
I'll be curious how these roll and how close the tolerances are between the design and printed item.
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I love this idea. Having been the poor SOB that assembled, aligned, installed, and realigned the test trucks on the 7 car train, (which took HOURS!) I look forward to this much simpler installation procedure.
In the event that this works and the bushings ARE required for reliable power pick up, I have 6 sets of assembled trucks for sale for those who want powered cab cars, haha. (Seriously though. Just the cost of the parts.)
Thanks so much for the effort in design version 2.0!
Craig
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Craig - if this works, count me in for 2 sets of trucks with the bushings -- 2 cab cars = 4 trucks.
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I love this idea. Having been the poor SOB that assembled, aligned, installed, and realigned the test trucks on the 7 car train, (which took HOURS!) I look forward to this much simpler installation procedure.
In the event that this works and the bushings ARE required for reliable power pick up, I have 6 sets of assembled trucks for sale for those who want powered cab cars, haha. (Seriously though. Just the cost of the parts.)
Thanks so much for the effort in design version 2.0!
Craig
I suspect that the electric pickup will be good on the revised truck. Since the contact area between the axle and one of the small-diameter wires is very small, the pressure at the contact area should be more grams per square millimeter than with the brass bushings. That seems like it'll actually improve the electrical contact. This desing is very innovative and "outside of the box". I hope that it shows a large improvement of the rolling ability.
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I suspect that the electric pickup will be ....
This design is very innovative and "out of the box". I hope that it shows a large improvement of the rolling ability.
Pedants alive! :scared:
"out of the box" would be the same... :o "outside of the box" would be different = innovative. :-X
Heh, so many munged metaphors from :ashat: , musta been a heavy weekend!
Regards Dave
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Pedants alive! :scared:
"out of the box" would be the same... :o "outside of the box" would be different = innovative. :-X
Heh, so many munged metaphors from :ashat: , musta been a heavy weekend!
Regards Dave
Part of it is my Polish heritage, and part of is inattention after a brain-melting 8-hour class. Is that good enough of an excuse? Give me a break - I only missed 4 letters. :D
Don't let the sleeping dogs bite, eh? :D
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It would be awesome if the new design provides good electrical pickup.
The bronze bushings worked well but did exhibit random drop outs. A keep alive would be needed, but I suspect we might see the same with the new design. You see it with Kato cars and they are what I consider to be the gold standard in passenger car trucks.
The holy grail here is electrical pick up AND better rolling.
Looking forward to testing the new design.
Craig
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Powdered graphite in the bushings? or maybe Conductalube?
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So its been a few weeks since last checking in with the somewhat improved BiLevel trucks, and I spoke of a version 2.0. Got a bit swamped with the day job, as well as other projects, but here is what I have been working on so far.
The idea was to do away with the bushings and associated misalignment issues, reduce contact area thus reducing friction, and generally simplify assembly. In this case, the truck frame has a series of holes pre-drilled in specific locations.
(Attachment Link)
These holes will allow for thin brass/steel/material of choice wire to be installed and act as very small load bearing surfaces. The horizontal wires will provide single point contact on the top of the axles, while the vertical wires have 0.0005" clearance (0.001" total clearance) for longitudinal play. Only one vertical wire should make contact with the axle at a time at each axlebox. The total contact area for the entire car is now reduced to 16 single points of contact (ok ok, not really if you consider actual hertzian contact theory, but we are talking microscopic contact areas), and I see no way to get less. Slight misalignment should not be problematic, as the wheelsets would still only make single point contact on each wire.
(Attachment Link)
(Attachment Link)
(Attachment Link)
(Attachment Link)
(Attachment Link)
The idea will be to simply glue the wires in place, trim to length, install wheelsets, and off you go. I still need to put in an upstop/wheelset retention method, which might just be a retention wire under the axle or a bit of a plastic protrusion to snap the wheelset in. I will also add the lateral bosses similar to what @Lemosteam had sketched out previously. After that, these will go to the printers for testing!
At this point I anticipate that electrical pick up will be completely unreliable, so the bushing trucks might still be necessary for electrified cab cars, but we will see during the next round of testing.
Oh, and just for clarification @peteski, I hid the plastic axle tubes in these screenshots to make it easier to see, but they still hold the wheelset spacing as before. :D
Cool!
I realize you are still in progress on this design so I have some thoughts.
How will you trap the axle from falling out now? I would not bend the wires over to trap the axle as it will close off your 0.005" gap in a hurry.
It might be good to design a 5-10% snap into the slot and leave the wires vertical, and with the extra material you could add a downward stop with a small pocket for the wires to prevent the loose wire ends from moving toward the axles, which I would bend in an inverted U first before insertion.
if the top wire is the electrical contact, I assume there is a way to connect to it somewhere in the truck?
Since the top wire would likely be phosphor bronze, would it make sense to have a side view parabolic curvature or gentle radius to force (under the weight of the car) the axle up and toward the four center wires (toward thew bolster center) for improved electrical contact? I realize this will double your friction but it may be a reasonable trade-off.
Enjoying this progression of design!
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The road testing of the train was done with graphite on the bushings. I graphite spray was apppied prior to assembly.
Craig
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Craig: You're ahead of me! So much for that idea...
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@craigolio1 , @CNR5529 -- just bumping this thread; wondering if there has been any new progress with the new design?
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I don't think this will ever be perfect but I do think something with reasonably reliable pickup could be made and it might be able to be done as a mod to the existing truck. At least for prototyping. I've acquired pretty extensive experience with this issue working on my miniature power trucks and have a few approaches that might be able to be adapted. If somebody has a truck or two that I could look at I would be willing to give it a try. Keep in mind though, in these ventures and in short quantities, ultimately cost can be an issue.
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@craigolio1 , @CNR5529 -- just bumping this thread; wondering if there has been any new progress with the new design?
The latest test prints should be here any day! I will then set up a test ramp to compare a stock car against rev 1 and rev 2 of the new truck design. Should be able to report on this very soon.
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[attachimg=1]
:D
These are soaking in bestine as we speak. You can see the channels for the wire bearings, as well as how the wheels will be retained (snap in place). I just hope the printing tolerances are good enough...
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(Attachment Link)
:D
These are soaking in bestine as we speak. You can see the channels for the wire bearings, as well as how the wheels will be retained (snap in place). I just hope the printing tolerances are good enough...
Suggestion, while soaking, snip off a piece of wire that you plan to use in the channels at a high angle and using a pin vise to gently rotate the wire like a drill to clean out the wax that I know is in those holes.
Will make your final assembly much easier.
Might want to re-soak after the wire is in, to clean off any wax transferred to the wire as you are feeding it into the holes.
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This is awesome. I can't wait get moving on this again. It was really exciting the first time.
Craig
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So an update is long overdue... I had assembled the trucks and conducted testing right before Christmas, but unforeseen circumstances kept me otherwise occupied and I wasn't able to write up a summary of my findings. So without further delay, here it goes!
After the bestine soak, installation of the bearing wires proceeded fairly uneventfully. I tried trimming the wire with a high angle per Lemosteam's suggestion, in order to "drill" out the holes. What I found however was that it tended to force the wire out of the channels in the openings, which in turn pinched the axles. When I cut the wires flush, and inserted them straight in (think pressing rather than twisting), the wire cleaned out the channel seats much more effectively, and the longitudinal axle bearing tolerance was restored.
[attachimg=1]
[attachimg=2]
It was then a mater of snipping off the excess wire and snapping in the wheelsets. (Though the excess wire was not yet trimmed in this photo)
[attachimg=3]
As is, the truck is now extremely free rolling. If I set it down on my desk, which apparently has the slightest grade, it rolls away on me without needing a push to break friction. That's a step in the right direction!
Next, I assembled a test rig, with dimensional parameters similar to that of @RBrodzinsky 's rig.
[attachimg=4]
[attachimg=5]
Tests were conducted with the rev 1 truck, the rev 2 truck and a stock car to act as a control and compare to previous test results. I also repeated the tests with the trucks by themselves, and assembled to the vehicles. This shows the influence of carbody weight on the various truck designs. So how did we do? Well here is some data:
[attachimg=6]
[attachimg=7]
[attachimg=8]
So what does this all mean? Well, generally speaking, Rev 1 trucks are better than stock, and Rev 2 trucks are better than Rev 1 trucks when considering distance traveled. In total, the rev 2 truck traveled almost 45% further than the stock truck. When the carbody was installed, the added weight did cause more friction to occur, and the end result is we have a vehicle with inboard bearing trucks which is now closer in performance to the Kato Amfleet Coach. Keep in mind I have yet to test the effects of lubricants on the Rev 2 truck.
One big improvement to the Rev 2 truck was a much reduced tuning time. It took Craig and myself quite a bit of time and effort to tune and align all the bushings in the Rev 1 truck for his train. In this updated version, it was a bit more work to thread the wires initially, but once this was done there was no need for optimizing or tuning. Also, if the installation was not done correctly (i.e. the wires aren't seated correctly or there is some print fuzz left), you know right away because the axles are not free to move.
On a level layout with fairly broad curves, we were able to haul a 7 car consist with the Rev 1 trucks using a single locomotive. Adding an 8th car would cause slipping to occur in the curves. I am guesstimating that the rev 2 truck should bring us closer to the 9-10 car mark, but this has yet to be tested.
Contact between the truck frame and axle has now been reduced to 2 points of contact at each journal, so I see no way of further optimizing the truck design. At this point the only way I see to get better performance would be to make the cars lighter. I am looking forward to testing out a complete trainset in the near future!
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Great work, and nice writeup!
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Looking at your first chart, I'm surprised by the difference between the MT hopper and reefer. I would have thought they'd be very close to the same.
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When I ran those, I too was very surprised. All my cars (the ones in green) have FVM metal wheel sets. Notice the reefer's performance is very similar to the cattle car, even though its mass is similar to the hopper. Made me wonder about differences in the trucks (but I didn't take it any further than wonder).
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Amazing!
Time to order some trucks and fit tiny Helium balloons in my cars.
Craig
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I hadn't caught up to the latest on this until now. Very interesting.
On electrical pickup... 4 wires from each truck? Do the three different wires of each bearing make good enough contact with each other that all provide reliable pickup?
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I haven't seen the trucks yet but when I did the ones with the bronze bushings I soldered one magnet wire to each of the four bushings on the truck, and then ran them up through the middle of a hollow king pin.
I would attempt to do the same here, somehow soldering the wire to the horizontal wires as that would be the one which was in contact most often. I haven't assessed how I'll do that yet. If it proves to look too ugly or just not work, I'll use the bushing equipped truck as before and equip the rest of the train with the new design.
Craig
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Rick: Does the hopper have 100-ton trucks with 36 inch wheels? If it does, maybe the 33 and 36 inch wheel axles are slightly different, or it could be as simple as one or more of the sideframes have been spread, or pinched, just a little over time. It is interesting, though.
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Sorry for the bad advice, @CNR5529 !
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So an update is long overdue... I had assembled the trucks and conducted testing right before Christmas, but unforeseen circumstances kept me otherwise occupied and I wasn't able to write up a summary of my findings. So without further delay, here it goes!
So what does this all mean? Well, generally speaking, Rev 1 trucks are better than stock, and Rev 2 trucks are better than Rev 1 trucks when considering distance traveled. In total, the rev 2 truck traveled almost 45% further than the stock truck. When the carbody was installed, the added weight did cause more friction to occur, and the end result is we have a vehicle with inboard bearing trucks which is now closer in performance to the Kato Amfleet Coach. Keep in mind I have yet to test the effects of lubricants on the Rev 2 truck.
This seems to confirm the suspicions I had at the beginning of this thread that (without using some esoteric design and components) Kato's inside-bearing truck design is as free-rollign as possible.
Contact between the truck frame and axle has now been reduced to 2 points of contact at each journal, so I see no way of further optimizing the truck design. At this point the only way I see to get better performance would be to make the cars lighter. I am looking forward to testing out a complete trainset in the near future!
Making the car lighter will decrease the reliability of electric pickup (for lighting). Probably an undesired consequence.
Thanks for your through and scientific presentation.
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Sorry for the bad advice, @CNR5529 !
Not at all. I had planned to do basically this anyways, but discovered that the alternate version (plunging straight in) provided better results in the fud/fxd material. This is of course purely a problem due to the half exposed wire geometry; a normal blind or thru hole should be "drilled" instead.
This seems to confirm the suspicions I had at the beginning of this thread that (without using some esoteric design and components) Kato's inside-bearing truck design is as free-rollign as possible.
Making the car lighter will decrease the reliability of electric pickup (for lighting). Probably an undesired consequence.
Now someone has to come up with a design using actual ball bearings, and keep it cost effective... :D
I suspect that any solid electrical design will require heavy use of "keep alive" capacitors. The rev 1 truck with bushings wasn't great pick-up wise, I'm guessing this one will flicker quite a bit as well.
Well, at least we have a better looking truck with improved performance. I am calling it a win!
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Now someone has to come up with a design using actual ball bearings, and keep it cost effective... :D
I suspect that any solid electrical design will require heavy use of "keep alive" capacitors. The rev 1 truck with bushings wasn't great pick-up wise, I'm guessing this one will flicker quite a bit as well.
Well, at least we have a better looking truck with improved performance. I am calling it a win!
I agree that for minimizing friction, ball bearings and very tight tolerances would be optimal. But ball bearings are very poor at conducting electricity. @mmagliaro tested that configuration and IIRC abandoned using ball bearings on his steam loco in favor of friction-type bearings to minimize electrical conductivity.
But yes, on couple of fronts, your design is an improvement over the original.
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You might be surprised how reliable this will be as long as you connect all three wires at each corner (two corners per side obviously).
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I'm not sure I'm following what you mean by "all three coroners, two corners per side".
On the previous design I connected one wire per wheel, for a total
Four wires per truck and four points of contact on each rail.
This provided power but we still saw spilt second interruptions in power, which with the car trailing means we would get brief flashes of the head light as the decoder powered up and then switched to the marker lights again.
The TCS decoder I used has attachments for a keep alive cap which will solve this issue. So I planned to use the same plan of four wheel pick up.
The issue is that the wires that the axles will be contacting are hidden in the truck now where as the bushings were on the axle and had the bottoms exposed which made it very easy to solder a wire into the bushing prior to installation, and the wires were not visible while running.
What I'm trying to figure out here is how to attach wires and have them hidden. My plan right now is to flare the hole in the end of the truck a bit so that I can solder the magnet wire to the end and when inserted, the solder connection will be hidden in the hole. The wire is then bent around the end, passes under the axle and up the king pin tube as before. The down side here is that if the wire ever breaks off I can't see a way to get the brass wire out of the hole in the truck.
My other idea was to cut a channel across the end of the side frame so that the wire pick up can be bent in at a 90 deg angle. The groove would mean the bent wire is flush with the end once inserted. The wire is soldered to this and if it breaks of it can be soldered back on or the brass wire removed and then resoldered. Having that bent piece of wire would leave a sort of handle.
Craig
Craig.
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I was under the impression that the bushing was held securely in between the wires (no play). If that's the case, using just s single wire for reliable pickup should suffice, no?
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I believe what Lemosteam was talking about was the three bearing wires that make up a single axle box (which now replaces a bushing). Only two wires are ever in contact with the axle at each corner because of the longitudinal clearance in the design. As you go from pull to push, the one wire would no longer make contact, and the one that was free will now be in contact. Thus, each corner of each truck would in theory need 3 wires to be joined together for robust electrical pickup. Thats a total of 24 points to solder together per car!
If it was my train, I would use rev 1 trucks with bushings for the cab car, and include keep alive caps... but we can still conduct some tests if you want with the rev 2 trucks and pickup.
I was under the impression that the bushing was held securely in between the wires (no play). If that's the case, using just s single wire for reliable pickup should suffice, no?
The bushings are no longer in use on the newest truck design. The bearing wires rest directly on the axles, effectively replacing the bushings. There is 1 thou total longitudinal play between the two guide wires and the axle, to allow for some freedom of motion.
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The bushings are no longer in use on the newest truck design. The bearing wires rest directly on the axles, effectively replacing the bushings. There is 1 thou total longitudinal play between the two guide wires and the axle, to allow for some freedom of motion.
Um, looks like I had a serious senior-moment. Never mind. :facepalm:
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I'd like to revisit this one since I'm just about done with my CalTrain MP36.
I originally just lurked on this one since I only ever planned to pull 5 cars; figuring a heavy unit like the MP36 would have no trouble there.
But after running a quick test with my new power, and having it stall on nothing more than medium curve on level track, I am now officially joining the quest!
Am I understanding this correctly that things were left off with only a 15% increase in rolling distance? As in, if the stock car rolled 100 inches, the improved car rolled 115 inches?
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Ah, this was a fun thread to follow!
I'll be interested to see how Rapido will handle inside-bearing truck design in their Comet cars. So far Kato seems to have the best design, but still far from what we would like. Unfortunately I think we have laws of physics working against us having really free-rolling inside bearing trucks in N scale.
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Bushings and the wire low friction trucks were an improvement over the stock arrangement, but not quite as much as we were hoping. The last attempt will be made inline with how Rapido is doing the comets and LRCs... actual ball bearings. I did source some that should work, but after two full trainsets worth of testing, hobby funds are temporarily being diverted to other projects. Now that I have a photon though, I can print prototypes at home!
Having seen the Rapido samples, I am confident that this will be the way to go, a good looking truck that rolls!
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Bushings and the wire low friction trucks were an improvement over the stock arrangement, but not quite as much as we were hoping. The last attempt will be made inline with how Rapido is doing the comets and LRCs... actual ball bearings. I did source some that should work, but after two full trainsets worth of testing, hobby funds are temporarily being diverted to other projects. Now that I have a photon though, I can print prototypes at home!
Having seen the Rapido samples, I am confident that this will be the way to go, a good looking truck that rolls!
Yes, ball bearings will work well (assuming that no grease but very light oil is used). The huge trade-off though is very poor electrical pickup (and passenger cars are often illuminated or even have DCC decoders for the cab lights). Max tried to use those on his steam loco and due to poor electrical performance decided against it. One could install wheel wipers, but that sort of defeats ball bearings. @mmagliaro - maybe you can chime in and explain? Or maybe Rapido solved the poor electrical conductivity? I guess I'll find out when I get my batch of Comets.
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For illuminated cars, why not use batteries? No track pickup needed.
For DCC it's more complicated, and I don't have a solution there, unless one wants to use head-end power, like the prototype. Two wires could do it, and they could be hidden by the diaphragms.
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For illuminated cars, why not use batteries? No track pickup needed.
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Because I hate batteries ! The need to be replaced (which means opening the car up), and often will leak electrolyte if left in the model, making a mess.
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I have seen this mentioned numerous times now, so...
Yes, I tested ball bearings for my 0-6-0 engine project. I was thinking they would be super cool, would provide almost frictionless motion in the driver axles, and with all those balls rolling around between the two races, I figured there would be excellent pickup. But slipping one on some axle stock, and turning the bearing while connected to an ohmmeter, I found that there actually was continuity through the bearing SO INFREQUENTLY as to be useless. I'd say I was lucky if there was a complete circuit even 10% of the time.
I did consider using them with back-of-the-wheel wipers. But I hate wheel wipers. I went with the bronze bushings.
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For illuminated cars, why not use batteries? No track pickup needed.
For DCC it's more complicated, and I don't have a solution there, unless one wants to use head-end power, like the prototype. Two wires could do it, and they could be hidden by the diaphragms.
I've stated using Rapido's Easy peasy lighting system on my passenger cars. Basically drop in, and can be turned on and off with a magnet. They use button Cell batteries.
Looking at their design, It would be fairly simple to modify their boards to use in pretty much anything....
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Having seen the Rapido samples, I am confident that this will be the way to go, a good looking truck that rolls!
Did you get any photos? I'm intrigued.
I did some initial experiments and my MP36 can now easily pull the 5 unit Baby Bullet without issue (and my 44 toner can pull 4 of them!), but I'm still struck by the challenge to get a 10 car train.
At this point, acquiring 5 additional Bombardiers may be just as difficult.
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Side note, if anyone has any sounder cars they want to sell, Let me know! lol
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Watched a set of 4 Bombardiers go for over 300 on eBay today. Guess I won't be getting more for myself anytime soon! :scared:
Here's my initial rolling test with a 3D printed 'knife edge' truck vs the original trucks. Originals didn't even make it down the ramp! :facepalm:
I also grabbed a Kato Amfleet for tinkering. My 'knife edge' truck rolls slightly better than Kato, however I believe I can do a similar treatment to the Kato metal edge bearing and achieve even better rolling and maintain electrical pickup. I have 5 pairs of Amfleet trucks on the way and will report back as testing continues.
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Well, I know this is a very old thread, but did anything ever come of your rev3? Did you publish rev1 or rev2 to Shapeways or Thingiverse?
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We shelved the project until the Rapido LRCs came out to see how those trucks compared. And they were terrible. Haha. Actually they roll very well now after some tuning. And during the tuning process @CNR5529 snapped some of the Rapido LRC wheels and bearings into his V1.0 truck (the bearings conveniently were the same size as the bushings.) They roll beautifully on their own and even better with some weight. Which is the opposite of the other Two designs. So the concept would would for the bombardier trucks as well. We just need to source the bearings that will fit the Bombardier axels. I haven’t looked in a while but they were pricey so we held off until we could play with the LRC trucks. I’m interested in moving forward with a V3.
Craig
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I’m a new participant on The Railwire, and have already learned a lot from recent discussions on Rapido’s N scale Canadian and FP9A releases. This got me thinking … “Jeez, if anyone might have come up with a way to improve the horrid rolling characteristics of those Athearn Bombardier N scale coaches, it would be these guys”. So, I did a search and found this topic.
Just had to laugh at Mark’s incline test - unfortunately, it is reminiscent of how, earlier this year, Rapido’s The Canadian coaches similarly got stuck at the top of a ramp, while Kato coaches would roll forever.
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I’m a new participant on The Railwire, and have already learned a lot from recent discussions on Rapido’s N scale Canadian and FP9A releases. This got me thinking … “Jeez, if anyone might have come up with a way to improve the horrid rolling characteristics of those Athearn Bombardier N scale coaches, it would be these guys”. So, I did a search and found this topic.
Just had to laugh at Mark’s incline test - unfortunately, it is reminiscent of how, earlier this year, Rapido’s The Canadian coaches similarly got stuck at the top of a ramp, while Kato coaches would roll forever.
The Canadian coaches roll well with some easy modifications/tuning. These Athearn cars how ever are paper weights if you train is longer than three cars. Since the replacement trucks stalled until a suitable bearing can be found, I moved onto modifying locomotive to have a couple of traction tires. It’s done but I don’t have a layout to test it on yet, and COVID killed any chance of my N-Trak group getting together.
Speaking of which, if you are in Toronto you should come and hang with us at a show sometime. We started as an N-Trak group and are now making the move to Free-Mo-N as many of us a trying to model more prototypical scenes.
Welcome to TRW. The quality of modelling, and people, here will inspire you.
Craig
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Craigolio, thanks for the warm welcome. I am indeed in Toronto. Well, Markham, to be more precise. In fact, I’m only 20 minutes from Rapido’s facility, so I had them scallop the I-beam under The Canadian coaches to improve rollability. It helped a lot, but I’ve since had to do lots of other tweaks. They roll much better, but still not as smooth and effortless as my Kato coaches, so I remain vocally critical, mainly because of the Rapido price point - premium cost for mediocre performance just rubs me with perpetual annoyance!
In non-covid times I frequent several annual train shows, and would very much like to meet you guys. My guess is that the Barrie show might be the first opportunity to do so, hopefully February 2022 … fingers crossed!
Within the last three days, I’ve been exploring DecoderPro for the very first time. Question- where do folks find those little loco icons that I see in their JMRI rosters?
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Clearly Rapido found more problems with micro roller bearings than they solves as they went with a solid bearing on the Comet cars.
I wish I could locate a good source for jewel bearings as they have solved the same issues in the watch industry for over a century. Obviously ordering a bearing custom made for this would be insanely expensive, but I wonder if two small jewel surfaces would work. This would essentially replace the wire bearing surface on your trucks with either a flat edge or rounded bearing.
This wouldn't conduct electricity, but I'm more concerned with just getting a sound equipped Kato F40PH to pull 5 or more cars.
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Clearly Rapido found more problems with micro roller bearings than they solves as they went with a solid bearing on the Comet cars.
I wish I could locate a good source for jewel bearings as they have solved the same issues in the watch industry for over a century. Obviously ordering a bearing custom made for this would be insanely expensive, but I wonder if two small jewel surfaces would work. This would essentially replace the wire bearing surface on your trucks with either a flat edge or rounded bearing.
This wouldn't conduct electricity, but I'm more concerned with just getting a sound equipped Kato F40PH to pull 5 or more cars.
I’m not really the guy to talk to about the engineering side of this. I’m more the testing and good humour side of things (and that’s a stretch - trying to make it look like I bring more to the table here). @CNR5529 may want to chime in here. He did all of the design on our two test versions.
Craig
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I was looking up bearings and found this:
https://www.microlap.com/products/jewel-bearings/olive-single-cut-bombe/olive-hole-single-cup-bombe-mt8004/
No idea what each one costs, but here you have a small inner shelf that reduces friction along the axle and a tapered end that would reduce friction if the wheel back rubs against it.
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I was looking up bearings and found this:
https://www.microlap.com/products/jewel-bearings/olive-single-cut-bombe/olive-hole-single-cup-bombe-mt8004/
No idea what each one costs, but here you have a small inner shelf that reduces friction along the axle and a tapered end that would reduce friction if the wheel back rubs against it.
While not fully enclosed Kato Amfleet truck bearings are pretty close to what you are looking for. I don't think that having the bearing closed (circular instead if U-shape) would give any benefits. Only to top part of the bearing is really being utilized in those trucks (since it always supports the weight placed over the bearing (the weight of the car). Also the more precise (tight fitting) the bearing is, the more critical the more perfect the alignment has to be. Tolerance-wise an N scale truck is nothing like a wristwatch movement.
As I see it the problem is that even at 1mm, the axles are very thick compared to the shafts in wristwatches. You could probably thin down the Kato bearings to reduce the contact area between the axle and bearing,
As for the ball-bearing experiment Rapid did, as soon I've seen that design, I knew it would be trouble. Unless fully sealed, ball bearings are very unforgiving of any debris that will get inside (and train layout is far from clean). Also, any lubricant applied to the bearing will dampen its ability to roll freely. Not a good idea for N scale trucks.
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I wonder if one more iteration of the PB wire trick could work. What if, from the center of the truck, the wire was fully sprung resting atop the axle with no direct hard contact to the truck frame, other than a groove for the axle to ride in vertically. This would leave only four single point contacts of friction to the wire to both axles. The only other source of friction would be the groove, which could be designed as a blunt knife edge in the plan view to minimize contact. Different diameter wire could be experimented with to determine the most appropriate spring rate for the weight of the car.
(https://www.therailwire.net/forum/gallery/26/2711-271021071344.jpeg) (https://www.therailwire.net/forum/index.php?action=gallery;sa=view&id=26256)
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Pete:
The bearings I linked to are a stock item and not custom made, so they might be attainable. I bet if the inside diameter of the jewel was larger than the axle, this would only have two points of contact across the entire axle and both would be a minimized jewel surface. Polishing the surface of the axle would also help greatly.
John:
I actually did this exact experiment with the new Bachmann Amfleets when they came out. It DID reduce friction, but not enough to make it on par with the Kato Amfleets. Even with a knife edge frame (in my case Delern, but this would be Shapeways plastic), there appears to be a lot of friction on the plastic-metal interface. I am convinced that we have hit a wall with what we can do with design, and now we need to focus on materials.
One of the things I noticed with the new Comets is that bearing appears to be machined and the bearing surface on the wheels is dull. That makes sense for a production model as this is the cheapest way to produce the cars. But both surfaces should be lapped and polished to a mirror shine. I have several polishing products used for watches - diamond paste in several sizes to remove scratches from sapphire glass and Cap Cod Cloth to remove scratches and polish steel watch cases. I think both might work here.
In addition, I think polishing the wheel tread may help as this is another point of friction we have not addressed yet.
I'm not expecting big improvements with any of these. But if we have a 15% reduction in rolling resistance with one and a 10% reduction with another idea, well that would equal another car on the train.
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The latest results from testing were a quick and dirty attempt at installing the Rapido LRC wheelsets and ball bearings in the Rev 1 (bushing) truck. It worked remarkably well, and was a direct fit in the truck frame. The big advantage I noted here was that where the bushing and wire truck versions were very free rolling on their own, they suffered from increased rolling resistance with the weight of the carbody, while the ball bearing truck seemed to decrease rolling resistance with the added weight. Bearings similar to the ones Rapido used are fairly cheap to source too, case in point:
https://www.aliexpress.com/item/32519049244.html?spm=a2g0o.productlist.0.0.50c01f72TM7xxv&algo_pvid=2738780c-8a1c-4443-9abe-cd34f397f04b&algo_exp_id=2738780c-8a1c-4443-9abe-cd34f397f04b-50&pdp_ext_f=%7B%22sku_id%22%3A%2257448762734%22%7D (https://www.aliexpress.com/item/32519049244.html?spm=a2g0o.productlist.0.0.50c01f72TM7xxv&algo_pvid=2738780c-8a1c-4443-9abe-cd34f397f04b&algo_exp_id=2738780c-8a1c-4443-9abe-cd34f397f04b-50&pdp_ext_f=%7B%22sku_id%22%3A%2257448762734%22%7D)
The problem people ran into with LRC cars not rolling was actually a problem with the Rapido truck frames and pickups being bent, and the bearings ending up being out of alignment. When I used those wheelsets in my straight/square rev 1 BL trucks, they ran perfectly so this should not be a problem.
Now for the bad news: the Athearn wheelsets do not have the same size axle diameter as the Rapido cars. Rapido went with a 1mm axle dia meaning they could source cheap bearings, while Athearn used a 1.2mm diameter (cant you guys just adopt the metric system already? :trollface:). This means we either need to source custom bearings, or get custom wheelsets to replace the Athearn wheels... both solutions are beyond my hobby budget for cars I basically have no need for.
So, TRW collective, here is the mission: Find a cheap ball bearing with a 1.2mm ID and approximately 3mm OD (the truck can be tailored to suite slightly different OD), or source inexpensive replacement wheels/disc brakes with 1mm axles.
I wonder if one more iteration of the PB wire trick could work. What if, from the center of the truck, the wire was fully sprung resting atop the axle with no direct hard contact to the truck frame, other than a groove for the axle to ride in vertically. This would leave only four single point contacts of friction to the wire to both axles. The only other source of friction would be the groove, which could be designed as a blunt knife edge in the plan view to minimize contact. Different diameter wire could be experimented with to determine the most appropriate spring rate for the weight of the car.
While that is an innovative solution to provide a sprung suspension (which would potentially mitigate derailment issues if there were any), I am not sure I understand how this would be a better solution than the Rev 2 truck with the straight wires. In the rev 2 truck, all the vertical load was already in single point contact with one wire at each wheel, and there was only a single point of contact at each wheel in the longitudinal direction as well.
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One thing I have learned about FUD is that it is very much like glass with respect to hardness, so the knife edge would be similar to the jewel bearing that Daniel posted. Also since the wire contact is never hard against another surface , the sprung wire will mitigate any variation in the axle position or diameter and under the weight of the car will always be in contact The travel limiter button I show, would only be contacted under severe loads (more than the car weighs) essentially haven a fully floating axle with one or two points of contact at a time depending on the direction of travel.
This is the difference from REV 2, which the wire is fully supported on both ends as it passes through the axle pocket and provides no deflection whatsoever. Rigid=suceptible to variation, i.e good on one side, more friction on the other.
Wondering if my idea provides the jewel bearing contact simulation, while removing the stiffness and rigidity from the contact wire.
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... while Athearn used a 1.2mm diameter (cant you guys just adopt the metric system already? :trollface:).
LOL! 1.2mm is as metric as they can get. 1.2mm = 0.047" so it is not a converted Imperial size. While it is not a whole number, it is just as metric as 1.5mm.
Early N scale manufacturers in Germany used 1.2mm shafts and axles in some of their models even before American manufacturers started offering domestically produced N scale models.. Yes, 1.2mm is a pain to deal with (since it is not as popular as 1mm, or 1.5mm), but it "metric system".
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I agree Daniel: even with minimizing and polishing the contact surfaces to reduce the friction in these internal-bearings trucks in N scale, it is likely a losing battle. But there is nothing wrong with trying. I just have a chuckle that at some point we might have N scale models with 8 (ruby?) jewels in them (like fine watches). :D
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LOL! 1.2mm is as metric as they can get. 1.2mm = 0.047" so it is not a converted Imperial size. While it is not a whole number, it is just as metric as 1.5mm.
To be fair, 0.047" is also 3/64" rounded off to the nearest thou... so I feel like it is meant to be a metric conversion of a fractional inch value... Either way, it is a difficult diameter to find cheap bearings for. :|
But I do agree, fleets of ruby/sapphire bushing trucks would be amusing!
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Beg to differ. :trollface: :trollface: :trollface:
3/64 = .047 x 25.4 = 1.1938, when rounded is 1.19, where rounding to the significant metric digit equivalent to thousandths of an inch (0.000 in. vs. 0.00mm)
So if you measured the diameter in three places it should average to 1.19, not 1.2 if it were 3/64" material.
Less than hairs I know, but 1.2mm material is a standard nominal metric wire diameter. :D :D :D
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All this renewed discussion of poor rolling performance inspired to pull out my N scale Athearn F59PHI loco and all six Bombardier bi-level coaches (GO train livery), and try them on my test oval of sectional Kato track (12 3/4” radius curves).
I had bought the six cars (two 3-packs) quite some years ago, and picked up the loco maybe one year later. It was disappointing to discover how dismal the rollability of the coaches was … to find that the loco couldn’t pull any more than three cars on my layout’s 1.5% grades was genuinely maddening. As a result, the set-up barely/rarely got any use.
So, as I said, I just revisited my GO train, only to find that the single loco could barely manage four coaches on that flat, level, simple test oval of Kato track. All these years, I have resisted trying a tiny blip of LaBelle 108 oil on the axles, but at this point, figured I had nothing to lose. It helped marginally - I added a fifth coach, and the loco could almost make it around the bends. I temporarily stuck a small weight on the cab and managed to get the five cars around the oval. But six? Forget it.
But it did get me wondering - did anyone ever manage to improve things by adding some weight to the loco? And if so, how much weight, where, and with what material(s)? I don’t think I saw any reference to this approach, anywhere in this entire thread. Just curious!
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There isn’t much room in the loco for additional weight. Although in my case I added a complete lighting package that took up space for wiring and such.
Craig
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Yeah, after posting the above I removed the shell, and Craigolo is right … there is no wiggle room in which to add any appreciable weight. I suppose there are other possibilities such as traction tires and/ or that frog snot stuff, but I’m not big on either of those.
When all is said and done, it looks like finding replacement trucks is the only viable option. But … which ones???
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A heavier locomotive would help. I haven’t investigated the Kato MP36. I wonder if it’s heavier and if so, could the chassis be fitted under the Athearn F59 shell? And then with investment and effort… how much would it help? I guess if we compared weights, found the difference, stack that much on the Athearn and see if it changes things?
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Just last night I did a quick-&-dirty weight test on the Athearn loco. I used tiny bits of sticky-tac, and gradually added 4” strips of plumber’s solder (the heavy stuff that’s 1/8” diameter and is used to sweat joints on copper pipe etc) to the shell exterior.
Started with a strip along the bottom edge of each side (ie - just above the fuel tanks and trucks). I then added two more on the roof, and then two more again on the roof, for a total of six 4” strips of solder weights. I had no way to actually measure/quantify the weight change, but my rough guess is that I was probably close to doubling the original weight.
Net result? The grossly overburdened little loco DID manage to pull all six crappy coaches around the oval, but not without STILL suffering some wheel spin on the curves.
So, I’ve decided “screw it”. I just picked up two packets of Microtrains “4-wheel Lightweight Passenger Car Trucks” (1017) and will finangle them onto two coaches to see what happens. I’m beyond caring about the prototypical truck appearance. No one who views my layout will ever know any different (mostly four little grandkids, their parents, my wife, the odd brother- or sister-in-law etc).
At this point, some ten years down the road, I’d rather see the F59HPI pulling six cars having plain black conventional trucks on them, rather than a maximum of only three cars which happen to have shiny brake rotors like the real thing!
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Just last night I did a quick-&-dirty weight test on the Athearn loco. I used tiny bits of sticky-tac, and gradually added 4” strips of plumber’s solder (the heavy stuff that’s 1/8” diameter and is used to sweat joints on copper pipe etc) to the shell exterior.
Started with a strip along the bottom edge of each side (ie - just above the fuel tanks and trucks). I then added two more on the roof, and then two more again on the roof, for a total of six 4” strips of solder weights. I had no way to actually measure/quantify the weight change, but my rough guess is that I was probably close to doubling the original weight.
Net result? The grossly overburdened little loco DID manage to pull all six crappy coaches around the oval, but not without STILL suffering some wheel spin on the curves.
So, I’ve decided “screw it”. I just picked up two packets of Microtrains “4-wheel Lightweight Passenger Car Trucks” (1017) and will finangle them onto two coaches to see what happens. I’m beyond caring about the prototypical truck appearance. No one who views my layout will ever know any different (mostly four little grandkids, their parents, my wife, the odd brother- or sister-in-law etc).
At this point, some ten years down the road, I’d rather see the F59HPI pulling six cars having plain black conventional trucks on them, rather than a maximum of only three cars which happen to have shiny brake rotors like the real thing!
I hear you. I hate shelf queens.
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I did a quick test on an incline track and found the Comets do run much better than the Kato Amfleet cars.
They seem to roll about 20-25% better. And about 4X better than the modified Bachmann Amfleet cars. Yikes! I don't have the Athearn bi-levels to compare it to.
One interesting note... I polished the wheels and axles of one Comet truck and found it to be more resistant than the non-treated comet truck. I have not treated the bearing cut yet so that may be the reason, but I would have thought any polishing would improve rolling qualities.
I did buy two additional cars - Con-DOT to replace broken parts on my MBTA cars as well as provide parts for experimenting on these trucks to get them to run better.
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I did a quick test on an incline track and found the Comets do run much better than the Kato Amfleet cars.
They seem to roll about 20-25% better. And about 4X better than the modified Bachmann Amfleet cars. Yikes! I don't have the Athearn bi-levels to compare it to.
One interesting note... I polished the wheels and axles of one Comet truck and found it to be more resistant than the non-treated comet truck. I have not treated the bearing cut yet so that may be the reason, but I would have thought any polishing would improve rolling qualities.
I did buy two additional cars - Con-DOT to replace broken parts on my MBTA cars as well as provide parts for experimenting on these trucks to get them to run better.
@daniel_leavitt2000
Could you perform another test for me (since you have a good setup for this test)? Disassemble the Kato Amfleet trucks and remove all the lubricant (Naphtha, lacquer thinner, or acetone, are perfect for degreasing), then test how well they roll. I suspect that the lubricant dampens their rolling ability. I think that is why Rapido doesn't lubricate them.
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Finally, success with a single Athearn F59 loco pulling six Bombardier bilevel passenger cars.
As mentioned above, I picked up a couple packets of Microtrains passenger trucks (kit 1017). After assembly, the shank is maybe 1 or 2 mm longer than the Athearn truck, and although the fit on the under-car truck mounting stem is a tiny bit on the loose side, the stock retaining screw does hold the MT truck in place.
Just out of curiosity, I quickly tossed together a 3 foot long incline with roughly a 3% grade, and let fly with a stock, crappy-rolling OEM coach. It was a slow crawl down the incline, with a couple of finger nudges as well. I then tried the coach that had just received the new MT truck … that’s right - just a single MT truck on one end, and the crappy stock truck on the other end. Suffice to say that this “hybrid” coach literally flew down the test ramp.
Based on this encouraging result, I outfitted five of the six cars with this hybrid truck arrangement. I left the sixth coach in it’s original despicable rolling condition. Even so, I’m pleased to say that the F59 loco actually pulled all six cars with no wheelspin whatsoever. For me, this is the first time that this has ever happened.
One slight downside - the MT trucks can’t accomodate my 12 3/4” radius test oval because the wider truck frame hits the coach body shell. The coaches did however work fine on a 19” radius curve.
With a successful test under my belt, I’ll be picking up enough MT trucks to replace all of the poorly designed Athearn units. It’s nice to finally see a reasonably lengthy GO Transit get-up work the way one expected it to ten years ago. In fact, I suspect that a 9 car train might even be possible on a layout without grades.
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MTL makes inside-bearing MTL trucks?
But seriously, if you don't mind losing the unique look of the prototype trucks, any Micro Trains truck will run as well as if it was sliding on ice. That is not surprising at all. I am however surprised that changing just one truck made such difference.
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I’ve always thought inside bearing trucks looked anemic anyway (literally - an iron deficiency).
Seriously, getting your cars to operate with the wrong trucks is better than not having them operate at all.
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I’ve always thought inside bearing trucks looked anemic anyway (literally - an iron deficiency).
Seriously, getting your cars to operate with the wrong trucks is better than not having them operate at all.
I find it interesting that in this day and age, on one hand we (well, many modelers) literally count rivets or critique shade of paint on a model, but on other hand we are ok to change trucks to something totally unprototypical, to be able to run the models on the layout. Not that there is anything wrong with that. :)
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Hey there Peteski, thanks for weighing in, because I always respect your comments.
Although I don’t consider myself a rivet counter, I DO have a very strong affinity, admiration and regard for prototypical details and accuracy replicated in miniature. And I gotta tell ya … it took me a long time to make the change to those Bombardier coaches (over 10 years in fact). I did so with some regret, since the original trucks do, admittedly, LOOK really nice.
Many times over the years I did online searches looking for corrective measures, to no avail. It was maybe five years ago while visiting an open house event at Scarborough Model Railroaders where I saw an Athearn F59 pulling nine coaches. I asked the owner how the heck he accomplished that, and he said that he had to swap in Kato trucks (turned out that this fellow is one of the top tech guys at Rapido Trains).
My most recent attempt to preserve the OEM trucks was the google search that brought me to this thread, and the impressive amount of R&D conducted by more accomplished folks than I, which still left things unresolved. I feel that I have truly given this issue a fair shake; I’ve looked and waited patiently for solutions; in short, I’ve tried. But after weighing all the pros & cons, I think Angus Shops summed it up best … for me, seeing six cars operating successfully with the wrong trucks is better than being limited to pulling only three coaches bearing the OEM trucks (or not operating them at all, which had been my situation for several years). Cheers.
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Well I did a bit of tinkering tonight:
Polished the wheels, bearings and plastic axle of the Rapido trucks with diamond paste (.25 micron) and Cape Cod Cloths. reinstalled in a stripped down Rapido truck - removing the brake shoes parts to avoid any contact.
Took apart a Kato Amfleet truck and washed with alcohol to remove lubrication.
I tested the trucks without car bodies as they are different weights and this could skew the test. They were tested with a grade, unscientifically, by nudging them with my finger.
The Kato truck was by far the best rolling truck of the group. It rolls almost as well as an outside bearing truck with metal wheels. This really surprised me, and proved Pete's theory right.
Next best rolling truck was the untreated Rapido truck. This rolls about 75% the distance of the Kato truck. Following this was the treated Rapido truck with about 50-65% the distance.
None of the trucks are what I would consider sleds. They all roll pretty well and I have a feeling that none should pose a problem with 5 car commuter sets.
As to why the Kato trucks roll better - I have a few theories.
1. The larger wheels create more angular momentum, keeping the wheel turning once in motion.
2. The thin wheel treads minimize contact area on the rail, reducing friction.
3. The bearing surface is minimized - a small blade of steel on a very thin axle.
4. The Rapido bearings may rub against the plastic axle if on a curve, causing increased friction.
Clearly my idea to polish the bearing and wheel surfaces didn't work out. Why is this? I'm not sure. Maybe the wheel coating also has some friction reducing properties?
Ideas to minimize friction on the Rapido trucks.
1. Adding graphite powder may help burnish the bearing surfaces, especially the plastic axle against the bearing.
2. Adding a Teflon thrust washer between the bearing and plastic axle.
3. Shortening the plastic axle enough so that it does not interfere with the bearing.
4. Adding a step inside the bearing to reduce the contact surface area with the axle.
Another idea would be to basically build a new truck:
1. Modify ESM wheels by cutting them in half, stubbing the ends and reducing the axle width to .75mm.
2. Use a jewel bearing that minimizes contact with the wheel face and axle.
3. Use an axle sleeve that does not touch the bearing surface under any conditions.
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Only partly relevant, but I attempted to improve the rolling qualities of the original Bachmann Amfleet trucks once, using graphite powder (Kadee Grease-em). It helped a lot, but only for a short period of time, then they reverted to their original sled-like characteristics.
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Thanks for verifying my idea about Kato trucks. We usually think lubricants will decrease friction but they are also viscous (even light oil), and they dampen the movement. This is even more pronounced with very small bearings, like in N scale trucks.
I agree with you that the (dry) Kato trucks roll so well because the axles are small the smallest diameter of the trucks you tested, and they are spinning in a relatively thin phosphor-bronze bearing. Kato also likely has the tightest tolerance of the bunch, and keeping everything aligned also minimizes friction.
I discovered the damping effect when playing with small ball bearings. They spun very freely when dry, but any lubricant (grease or even light oil) would impede their free spin. But I also discovered that they spun the longest when lubricated with a very low viscosity fluid (Naphtha). But unfortunately it evaporates rather quickly. That was an accidental discovery while I was cleaning the lubricants out of the bearing.
I do like the idea of trying dry lubricant like graphite or Teflon. That might work.
The tread width IMO has no bearing on this. Only a very narrow area of the thread is on contact with the rail with any width tread.
Looking at the construction of the Rapido truck, I don't think that the plastic axle tube ever comes in contact with the brass bearing. The bearing has a hollow area on its inner side to prevent that from occurring. I think that the inside face of the wheel on the opposite side contacts its bearing before the plastic axle can come in contact with the bearing.
(https://www.therailwire.net/forum/gallery/26/2700-201021160420-26180522.jpeg)
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Funny you mention this, as I just shot myself in the foot with this very concept (oil) on my little 1829 "Rocket" project.
Let's just say that with such a tiny, extremely light engine, you want everything spotlessly dry and clean. Oil, even a drop of very light oil, just made it sticky and made the wheels drag. So, after taking things apart and cleaning it all with acetone, it is back to it's dry, clean self. I can't believe I even tried oil. I always tell people not to try oil to fix *anything*. :facepalm:
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Is it possible to obtain these trucks at all? It's been a while and I haven't heard anything from this.
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Is it possible to obtain these trucks at all? It's been a while and I haven't heard anything from this.
So @CNR5529 and I kind of stalled on the project. The bronze bushings worked much better but not remarkably. The next version using a PB bronze wire suspension system worked as well but not much better than the bushings. The next thing we wanted to try was bearings. But we couldn’t find any that fit the odd size Athearn axel that weren’t prohibitively expensive.
So as far as availability? Well I should let @CNR5529 chime in here but I’m willing to bet he’d print them for you if you want to play but with the caveat that they may not work and you are experimenting at your own investment/risk.
Now, I bought a bunch of Rapido LRC cars and a half dozen of them didn’t roll. Rapido repeatedly sent me new trucks until I had enough to make the cars roll. They didn’t ask for the old trucks back so I started to play with the parts from them. Specifically the wheels and tiny wheel bearings. Conveniently the bearings snapped perfectly into the V1 bronze bushing truck. They don’t fit the Athearn axels, (remember the odd size?), so I used the Rapido wheels as well. They are a slightly smaller diameter and they don’t have the disc brakes. However they do roll remarkably better.
It’s not reasonable, I don’t think, to purchase mass quantities of LRC trucks from Rapido but it shows that the possibly of using bearings has merit.
Also I had two wheels on the F59 modified by a friend to add traction tires made from black shrink tubing. It fit and tan fine but unfortunately I didn’t have a loop to properly test it’s capabilities at the time. Since then the tubing has become brittle and failed. Also since then I’ve acquired several Rapido locos tat had TT wheels which I removed. So with some spare traction tires in hand I planned to use THEM on the F59. Buuuut they are slightly wider than the grooves I had cut. So next up is a planned trip to see my friend and get wider groves cut.
I still don’t have a loop to test them on but that’s coming soon. In the next couple of months track work around my room will be complete and I’ll have a 40ft race track. At that time I’ll get the loco done and pull the test train with a combination of V1 bronze bushing cars and V1 Rapido bearing cars.
That’s where I’m at on the project right now.
Craig.
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So @CNR5529 and I kind of stalled on the project. The bronze bushings worked much better but not remarkably. The next version using a PB bronze wire suspension system worked as well but not much better than the bushings. The next thing we wanted to try was bearings. But we couldn’t find any that fit the odd size Athearn axel that weren’t prohibitively expensive.
So as far as availability? Well I should let @CNR5529 chime in here but I’m willing to bet he’d print them for you if you want to play but with the caveat that they may not work and you are experimenting at your own investment/risk.
Now, I bought a bunch of Rapido LRC cars and a half dozen of them didn’t roll. Rapido repeatedly sent me new trucks until I had enough to make the cars roll. They didn’t ask for the old trucks back so I started to play with the parts from them. Specifically the wheels and tiny wheel bearings. Conveniently the bearings snapped perfectly into the V1 bronze bushing truck. They don’t fit the Athearn axels, (remember the odd size?), so I used the Rapido wheels as well. They are a slightly smaller diameter and they don’t have the disc brakes. However they do roll remarkably better.
It’s not reasonable, I don’t think, to purchase mass quantities of LRC trucks from Rapido but it shows that the possibly of using bearings has merit.
Also I had two wheels on the F59 modified by a friend to add traction tires made from black shrink tubing. It fit and tan fine but unfortunately I didn’t have a loop to properly test it’s capabilities at the time. Since then the tubing has become brittle and failed. Also since then I’ve acquired several Rapido locos tat had TT wheels which I removed. So with some spare traction tires in hand I planned to use THEM on the F59. Buuuut they are slightly wider than the grooves I had cut. So next up is a planned trip to see my friend and get wider groves cut.
I still don’t have a loop to test them on but that’s coming soon. In the next couple of months track work around my room will be complete and I’ll have a 40ft race track. At that time I’ll get the loco done and pull the test train with a combination of V1 bronze bushing cars and V1 Rapido bearing cars.
That’s where I’m at on the project right now.
Craig.
If it's not that much of an improvement then I think I will be fine.
I wonder if there are any tips on getting the rapido Budd cars to roll better. Their amtrak horizon cars roll amazingly well like the kato autoracks, and yet the via rail Canadian cars do not roll as well, despite both trucks being outside bearing.
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Simsuper, you’ve touched on two of my biggest disappointments in fifty years of N scale modeling … dismal rollability of Rapido’s The Canadian coaches, and the star of this thread … Athearn’s horrible Bombardier trucks.
Regarding the former, my solution was two-fold - I dropped off the coaches at Rapido so that they carried out their prescribed fix (slight improvement), and then added a dcc-equipped Intermountain B unit … the ABA consist pulls the coaches effortlessly, and looks magnificent to boot.
With the latter, I ended up replacing the useless Athearn bogies on all six coaches with Microtrains 1017 lightweight passenger car trucks. My preference was to give up prototypical wheelset appearance for functional on-layout usability. My single Athearn F59PHI loco now hauls all six coaches, up 1.5% grades, all day long. The difference in rollability was nothing less than astounding.
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Simsuper, you’ve touched on two of my biggest disappointments in fifty years of N scale modeling … dismal rollability of Rapido’s The Canadian coaches, and the star of this thread … Athearn’s horrible Bombardier trucks.
Dwigth,
You forgot to also mention Bachmann Amfleet cars with their inside-beating trucks (both he original release and the "new improved" models). They are on par with Athearn Bombadier cars. :)
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If it's not that much of an improvement then I think I will be fine.
I wonder if there are any tips on getting the rapido Budd cars to roll better. Their amtrak horizon cars roll amazingly well like the kato autoracks, and yet the via rail Canadian cars do not roll as well, despite both trucks being outside bearing.
I did a few things to my Canadian trainset which improved the rolling quite a bit,
1. Check the trucks for flash. A few of mine had it.
2. File a notch out of the centre sill to keep the inboard axel from rubbing
3. Gauge the wheels
There may have been some other things. Grant from SAR did a great video on tuning the set:
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Craigolio - thanks for taking the time to respond with the pointers.
As I said, within a few days of receiving the set, Rapido carried out the prescribed “dremel surgery” if/where required, and I studied Grant’s instruction videos and had some ensuing correspondence with him. And yes, when all was done, the coaches rolled significantly better.
Maybe I’m being overly critical, but I can’t help comparing the 10-car Canadian to my 12-car Kato Morning Daylight coaches. The latter are truly impressive, smoothly gliding along the rails with the slightest touch. A single Rapido locomotive can easily pull all 12 lighted Kato cars, but still struggles with The Canadian even after all the changes. At this point, I feel the Rapido set is as good as it’s gonna get, and I can’t help thinking “if Kato can do it, then there’s no good reason why Rapido should be any less capable”.
Above ALL else, I am genuinely grateful that Rapido produced The Canadian, in N scale, in such remarkably admirable detail. It’s a beautiful, museum-quality piece, and it remains my premiere pride & joy. It’s better to have The Canadian with a niggly shortcoming or two, than to not have The Canadian at all!
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I did a few things to my Canadian trainset which improved the rolling quite a bit,
1. Check the trucks for flash. A few of mine had it.
2. File a notch out of the centre sill to keep the inboard axel from rubbing
3. Gauge the wheels
There may have been some other things. Grant from SAR did a great video on tuning the set:
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For me, the trucks themselves just do not roll well enough. I wonder if swapping wheels with different ones will help at all. How is it that the rapido horizon cars can roll so well, but their Canadian cars do not.
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You guys are so right. If Kato has been able to do it for so many years then why not Rapido. Same goes
For re inventing the wheel when it comes to loco mechs.
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You guys are so right. If Kato has been able to do it for so many years then why not Rapido. Same goes
For re inventing the wheel when it comes to loco mechs.
I'm just going to say Kato: in-house designed and made in Japan. I really think it's that simple