TheRailwire
General Discussion => N and Z Scales => Topic started by: Cajonpassfan on February 13, 2023, 01:22:10 AM
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In my opinion, Athearn's Challenger model is a great looking, good sounding, impressive locomotive. Given the complexity of the two independent driver assemblies and their siderod assemblies, the pilot and engine trucks, and the seven-axle centipede tender, it's an impressive feat of miniature engineering and design.
But, and I mean BUT: the electrical pickup is marginal, especially given the weight (6.7 oz.!) and the number of wheels available for electrical pickup: 34!!! My engine, with its ten axles only picks up power on the three rear drivers, and one of them has traction tires, pretty much negating its use for electrical pickup. The front engine, pilot and trailing truck have no pickup, as far as I can tell. So that's two out of ten axles... :?
The centipede tender has a fixed, five axle frame with the front four of the five picking up current, and a four wheel truck that's designed to pick up power except it doesn't. I haven't yet figured out why not; there are copper strips that should but don't. The four axles that do only have a 1.5" wheelbase, too short for reliable pickup.
And, issue number two (if I can overcome the pickup problem): my engine is a wimp as to its pulling power, as delivered. A much smaller and lighter Kato or BLI mikado will outpull it, hands down. I'm having a hard time understanding why a loco of this size and weight should have so much trouble pulling six MT (lightly weighted) Pullmans up a 2% grade. The mikes do it with no sweat....
I'm not here to bitch, just looking for solutions others may have found. The prototype was a powerful locomotive designed to handle heavy freights (and passenger trains unassisted). My Challengers (I own four :facepalm:) just don't do the job...
Suggestions and advice appreciated.
Otto K.
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Are these old release? 2017 release? Do all 4 of yours have the exact same symptoms? (i.e. electrically dead front engine trucks, dead front tender truck).
Those sound nothing like the couple of early Challengers I had here once to repair (for some of the motor and internal wiring problems that plagued some of the 1st release). They definitely are supposed to pick up power on both engine trucks and the front tender truck. At first, I'd say you have a broken wire or something like that. But not if all 4 of your engines have the same symptoms.
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As pointed out by mmaglario, your challenger SHOULD pickup from the loco's front driving truck (four wheels, since 2 have traction tires) AND the all four wheels of the front tender truck. I found the wiring on my 2017 release to be pretty sloppy... poor solder connections, pinched wires, the wiring connections of the front tender truck shorted out sometimes on curves, and more. As part of a decoder swap, I eventually re-wired the entire tender of my challenger, and it has great pickup.
As for tractive effort... my challenger isn't really a wimp, but does not pull as well as might be expected for it's wheel arrangement. It can pull 20-22 MTL freights/caboose around my small layout, which has 1.8% grades on 17" radius curves, before it starts to slip. Another challenger sent to me directly from Athearn (as a replacement/loaner when mine went back to the factory in China for warranty refurbishment, long story...) would barely pull 8 MTL freights around my layout. I watched it pretty carefully, and it became clear that the traction tires of the second were not actually making contact with the railheads (confirmed with a feeler gauge slipped under the wheels). As I was communicating with Athearn about this problem, mine came back from its trip to China, and I was able to do a direct comparison... and chose to keep my original and return the "loaner."
One of the things I contemplated doing with the anemic pulling challenger, should I need to keep ti, was to try to re[place the traction tires with something thicker, either from Athearn or maybe Love Hobbies. Another remedy I considered was to either scrap the tires and try building up the wheels with Bullfrog Snot, or maybe try a thin layer of Bullfrog Snot applied over or under the existing traction tires. I never did try any of these... so if you do, I'd be curious what (if anything) works. I wouldn't mind increasing the pulling power of my challenger... Good luck!
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Are these old release? 2017 release? Do all 4 of yours have the exact same symptoms? (i.e. electrically dead front engine trucks, dead front tender truck).
Those sound nothing like the couple of early Challengers I had here once to repair (for some of the motor and internal wiring problems that plagued some of the 1st release). They definitely are supposed to pick up power on both engine trucks and the front tender truck. At first, I'd say you have a broken wire or something like that. But not if all 4 of your engines have the same symptoms.
Hi Max, thanks for your response. Good questions. I have one of the original MRC equipped ones, two of the 2013/2014 releases, and another 2017 (couldn't help myself when the TTG scheme came out; too pretty even though they never ran over Cajon).
I spent a part of the day cleaning the wheels and contact points and only one has the dead front engine pickups, the others pick up okay when cleaned. I'll get in there to see what's going on when I have time, but I think I'm on my way to fixing the pickup issues.
The lack of pulling ability is another story. I can only get about 11 40' cars up the Hill, and maybe five plastic MT heavyweights. One of them threw a traction tire, again, so instead of replacing it, again, I ordered some Bullfrog Snot. (I find the very idea of it somewhat distatesful, but at this point I'll try anything: I need one Challenger to to pull the eleven car Pony Express, the last UP steam powered train in and out of Southern California, up and over Cajon Pass unassisted, just like the prototype. That was the whole point of assigning these engines to the train...
Dave, thanks for your comments also. One would think an engine that size and weight should pull stumps. No such luck. I'll try the snot I mentioned earlier, and also check the TT wheel contact with the rail...interesting observation.
If there is anyone out there who owns one or more of these, I'd be interested in your experience with the pulling ability of these things.
Thanks and kind regards,
Otto K.
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Honestly, Bullfrog Snot isn't going to grab as well as a rubber traction tire. You might be able to build it up thick enough to make better contact and work better than what you had, but not as well as getting the rubber tire wheels to really touch the rail properly.
There are some things you can try.
Cut a super thin strip of masking tape, (the width of the traction tire), with a steel straight edge and an Xacto.
Wrap it into the bottom of the traction tire groove (while the tire is out). Make sure you trim it so the ends
just meet together, do not overlap or leave a gap in the tape, or you will get a tiny hop or blip in the running.
Then put the traction tire on over it. This effectively makes that driver just a few thousandths bigger so the
tire will touch the rail better. Do that on both sides of the driver that isn't making good rail contact (which I would bet is the forward one) If that doesn't help, try a strip of electrical tape, which is thicker.
Do both engine trucks really swivel freely up and down so that over curves and imperfect track, those TT wheels
really lay down on the rail? Try to run it ultra-slow and shine a bright flashlight at the rail-to-wheel contact to see if there is a gap.
Do both engine trucks really drive? If it is sitting on its back running in a cradle, slowly, and you gently put some pressure on the forward drivers, do they by any chance stop and let the rear drivers keep turning (or vice versa)?
I fixed an early one that had a joint/ball problem that caused one engine truck to not really be powered, just free-wheel along the track.
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As pointed out by mmaglario, your challenger SHOULD pickup from the loco's front driving truck (four wheels, since 2 have traction tires) AND the all four
Ah, thanks for this explanation. I was confused by the "front truck" nomenclature. To me front truck (or more properly named "leading truck") is the 4-wheel free-rolling truck at the front of the locomotive, and rear truck (or properly named "trailing truck") is the free rolling truck in the back of the loco.
What you guys are calling "trucks" are the powered parts of the drive train. They have 8 wheels, siderods and cylinders. Those are actually called engines.
I was confused because the "front truck" you were describing, does not pick up power from the truck. Same goes for the "rear truck". But both engines are supposed to pick up power through all 8 (not 4) wheels (well except the traction tire driver which does have electric wipers, but the traction tire is an insulator). So actually 6 wheels on that engine would pick up power
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@mmagliaro Max, thank you for the response. Yes the engine assemblies swivel freely, and both sets of drivers exert equal effort. I took your flashlight advice and it seems that all wheels are seated on the rails. When I apply power and grab the tender, the wheels spin freely but the tractive effort is quite obviously weak. When pushed gently along the track, without power, the loco slides along quite easily, with very little apparent friction.
I did notice the TT slot is only .031" wide and the non-grooved part of the tire .022". Looking at where the wheels sit on the rail, it looks like the non-grooved outside surface rides the rail? This would be good news for electrical pickup, not so much for traction, pics attached. I do need to dust the old girl....
With all the Athearn Challengers sold, I'm surprised no one who has one has chimed in about their personal experience with these engines' tractive effort. It would be good to know whether this is common, or whether I got lemons...
Thanks,
Otto
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What you guys are calling "trucks" are the powered parts of the drive train. They have 8 wheels, siderods and cylinders. Those are actually called engines.
I was confused because the "front truck" you were describing, does not pick up power from the truck. Same goes for the "rear truck". But both engines are supposed to pick up power through all 8 (not 4) wheels (well except the traction tire driver which does have electric wipers, but the traction tire is an insulator). So actually 6 wheels on that engine would pick up power
Yes, on the prototype I would refer to them as "engines"... but it just didn't seem right referring to them as "engines" in the model (and what you refer to as forward and rear trucks I refer to as leading and trailing trucks). Since it is a challenger (4-6-6-4), and each "engine" has one pair of drivers with traction tires, there would be 4 wheels picking up power in each engine.
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Otto, even with those thin tires located close to the flanges I believe they will be in good contact with the track. If you have short piece of track, place it against the driver whit the loco upside down (so you can clearly see where the track will touch the wheel treads). That will likely show you that the traction tires are in optimal location, even if you shift the track from side to side until it hits each flange. Assuming of course that the wheels and track are in-gauge.
If the traction tires aren't working then I suspect that either the driver sits too high in the frame (not enough weight on that driver, or the tire lost some of its elasticity (stickiness).
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Yes, on the prototype I would refer to them as "engines"... but it just didn't seem right referring to them as "engines" in the model (and what you refer to as forward and rear trucks I refer to as leading and trailing trucks). Since it is a challenger (4-6-6-4), and each "engine" has one pair of drivers with traction tires, there would be 4 wheels picking up power in each engine.
You are correct of course - for some reason I had a Big Boy (4-8-8-4) on my mind. Sorry.
As for the names, I prefer (and think) it is clearer when using the names used for the 1:1 locomotive. There is nothing wrong with using the proper lingo.
Also, I did use "leading" and "trailing" truck names, but for some reason you edited that out your when you quoted my post.
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Okay, Otto. This is good work so far. You are narrowing it down.
What you said about the traction tire width made a lightbulb go on.
Have you carefully checked the wheel gauge on those drivers? The tires are thin, and set close to the flanges.
So if the driver gauge is narrow, then the tires will tend to ride inside the rails, as you are observing. I'd set the drivers on the "wide side" of "in gauge" in the NMRA notches to get the flanges a little more up against the insides of the rails, and see how that does.
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Also, I did use "leading" and "trailing" truck names, but for some reason you edited that out your when you quoted my post.
I missed that reference in my (too quick) reading... and just grabbed the later paragraph in my quote. My humble apologies.
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I missed that reference in my (too quick) reading... and just grabbed the later paragraph in my quote. My humble apologies.
No problem Dave. I too can too often be guilty of this. I just wanted to set the record straight.
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Is it just me or does it look like the wheel opposite the driver with the TT, does not have a TT? Maybe the image is just blurry.
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Is it just me or does it look like the wheel opposite the driver with the TT, does not have a TT? Maybe the image is just blurry.
I think you are onto something. If the TT is supposed to be black, the wheel at the top of the photo doesn't seem to show a black TT in the groove. It is just shiny metal.
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That wheel definitely doesn't have a tire on it. I didn't say anything because I assumed it was the one that threw a tire, as the OP mentioned several posts back. But maybe I'm wrong in that assumption.
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Guys :facepalm:
Yes, the pic is of the loco I mentioned in Reply #3, that threw the TT again, and yes it illustrates the empty groove that I measured and noted above. It also shows on the other side how narrow the black TT's are. Sorry about the pic quality, best I can do with an iPhone.
The point here is that NONE of my Challengers, with TT's intact, pull well, and never did, even when brand new.
I've been busy, so I've yet to try Max's suggestion to check the gauge and adjust it if under. He may have something there, that would in theory place a greater part of the TT over the rails where they might actually do some good.
Thanks for your interest,
Otto
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That wheel definitely doesn't have a tire on it. I didn't say anything because I assumed it was the one that threw a tire, as the OP mentioned several posts back. But maybe I'm wrong in that assumption.
A correct assumption, Max 8)
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Guys :facepalm:
Yes, the pic is of the loco I mentioned in Reply #3, that threw the TT again, and yes it illustrates the empty groove that I measured and noted above. It also shows on the other side how narrow the black TT's are. Sorry about the pic quality, best I can do with an iPhone.
The point here is that NONE of my Challengers, with TT's intact, pull well, and never did, even when brand new.
I've been busy, so I've yet to try Max's suggestion to check the gauge and adjust it if under. He may have something there, that would in theory place a greater part of the TT over the rails where they might actually do some good.
Thanks for your interest,
Otto
Ah, but the pic is with the text that mentions the drivers being on the track. As such I assumed that loco was the one you investigated for track contact.
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Is it just me or does it look like the wheel opposite the driver with the TT, does not have a TT? Maybe the image is just blurry.
Definitely no traction tire. That COULD be a problem, eh??
Cheerio!
Bob Gilmore
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Definitely no traction tire. That COULD be a problem, eh??
Cheerio!
Bob Gilmore
I give up :facepalm:
Let me say it again: "The point here si that NONE of my Challengers, with TT's intact, pull well, and never did, even when brand new"...
Otto
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What do I win?
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What do I win?
A Chocolate fish :D :D :D
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I give up :facepalm:
Let me say it again: "The point here si that NONE of my Challengers, with TT's intact, pull well, and never did, even when brand new"...
Otto
Otto,
I would think that having only one traction tire would be more troublesome than not having any...that was my point. On my engines, if one traction tire goes away, and I don't have a replacement, I take the other traction tire off until I can run it with both traction tires...especially steam engines. That probably doesn't increase tractive effort, but they run smoother.
I'd write a comment about all nine of my Athearn Challengers being great pullers/runners, but I only have one little grade on my layout, so my running experience isn't the equivalent of yours. Mine will pull 35 40' cars and a caboose without any slippage, but that's the maximum length train on my layout because of my center siding length, and all of my Challengers are relegated to freight/helper service since my era is later than yours. Incidently, that's also what my Athearn Big Boys pull without problems...adding a couple more cars to my Big Boy trains, and they start to slip on my short, little grade at Echo Curve.
Hope you find a solution...
Cheerio!
Bob Gilmore
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Dave, thanks for your comments also. One would think an engine that size and weight should pull stumps. No such luck. I'll try the snot I mentioned earlier, and also check the TT wheel contact with the rail...interesting observation.
If there is anyone out there who owns one or more of these, I'd be interested in your experience with the pulling ability of these things.
Thanks and kind regards,
Otto K.
Count me among the Athearn Challenger owners (in my case the Northern Pacific Z10 variety) who has one with poor pulling power.
It was immediately obvious to me when watching it that the drivers with the traction tires were not touching the rails, riding higher than the other drivers by a very tiny amount.
Fixing it has been on my to-do list for a while. Is there a bearing block under that driver where something can be inserted to make it sit lower? I was also wondering if a third party traction tire might be a little thicker and close the gap. Maybe some weight added inside the shell over the drivers will shift the weight distribution and hold the traction tires lower?
Jim B.
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What do I win?
Impressive! But you win nothing :D Not until you tell us what you did to it.
And I see flat track...what can it pull up a 2% grade?
Bob, I should have left the broken TT out of the conversation, I was just tired of having to replace them.
My other Challengers, with TT's intact can pull 30 cars on the level, but die on the mountain...
Thanks, Otto
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Impressive! But you win nothing :D Not until you tell us what you did to it.
And I see flat track...what can it pull up a 2% grade?
Yeah, Its all flat and level, I have not had much of an opportunity to run it on grades. I estimate it should loose about 10 cars with grades involved.
As for what I did, Added weight in the boiler, with as much as I can focused over the gear towers. Re-gauged everything to be dead on. Fine tuned all the The quartering to be as close to dead on as I could get it. biggest thing I did was widen the traction tire grooves in the drivers, and installed wider and thicker traction tires. I wouldn't suggest this to anyone, unless you got a lot of experience working on steam, and don't mind risking destroying parts. it wasn't easy.
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I dont own any steam but only pulling that car count seems kinda lethargic for a loco that heavy with 6 driven axles.
Heck I have an sw1200 weighing half as much that pulls 50 cars. Do all those idler wheels spin freely? Im thinking that there is one or more that have excess drag acting like a brake sled. Maybe the electrical pickups can be modified to minimize drag?
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You widened those grooves? ROCK AND ROLL, man. That is a great solution, but like you said, not easy.
Did you do it in a lathe or did you use some home-brew scheme like running it on its back and carefully holding
files or a Dremel in there?
Are the traction tire drivers on the Challenger pinned to the rods? Or are they just geared with the rods running around
in front of them for show?
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Yeah, Its all flat and level, I have not had much of an opportunity to run it on grades. I estimate it should loose about 10 cars with grades involved.
As for what I did, Added weight in the boiler, with as much as I can focused over the gear towers. Re-gauged everything to be dead on. Fine tuned all the The quartering to be as close to dead on as I could get it. biggest thing I did was widen the traction tire grooves in the drivers, and installed wider and thicker traction tires. I wouldn't suggest this to anyone, unless you got a lot of experience working on steam, and don't mind risking destroying parts. it wasn't easy.
Wow, you do win a prize! Like I said earlier, impressive!
Widening the grooves is way beyond my skills and tolerance for disaster. Just replacing the tires creeps me out, because (yes Max) they are pinned, and the rear one is especially tricky with multiple layers. And as to adding weight, I didn't think there was room, I sure would like to see how you managed that. Got any pics or advice?
Otto K.
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See, where I'm going with this is I'm wondering if the grooves could be widened in a lathe. The cutting is the easy part.
Figuring out how to hold them in a lathe chuck is the tricky part.
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I dont own any steam but only pulling that car count seems kinda lethargic for a loco that heavy with 6 driven axles.
Heck I have an sw1200 weighing half as much that pulls 50 cars. Do all those idler wheels spin freely? Im thinking that there is one or more that have excess drag acting like a brake sled. Maybe the electrical pickups can be modified to minimize drag?
Yea, Jeff, that the point, she should pull stumps but doesn't. I checked all the other wheels for drag, nothing out of the ordinary. The pilot and trailing trucks don't lift at all, just go for the ride. Baffling...😬
Stick with your stinky diesels :D
Otto
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See, where I'm going with this is I'm wondering if the grooves could be widened in a lathe. The cutting is the easy part.
Figuring out how to hold them in a lathe chuck is the tricky part.
Way beyond my paygrade, Max... :D
I tried to work with my newest Challenger tonight. I did widen the gauge a bit, per your suggestion. One of the TT axles was narrow. I also put two 1/4 oz. weights on TOP of the engine just to see what that would do. Substantial improvement in both pickup and traction, I was able to pull an eight car MT "heavyweight" train up the Hill. Not nine, and these cars are quite light, about 1.4 oz/40 grams for an 85' car. I felt good about it until I tried one of my stock BLI F units on the same trainset and it walked away with nine... So it's still a wimp in my book...
Otto
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Way beyond my paygrade, Max... :D
I tried to work with my newest Challenger tonight. I did widen the gauge a bit, per your suggestion. One of the TT axles was narrow. I also put two 1/4 oz. weights on TOP of the engine just to see what that would do. Substantial improvement in both pickup and traction, I was able to pull an eight car MT "heavyweight" train up the Hill. Not nine, and these cars are quite light, about 1.4 oz/40 grams for an 85' car. I felt good about it until I tried one of my stock BLI F units on the same trainset and it walked away with nine... So it's still a wimp in my book...
Otto
Diesel models will always have advantage over steam locos. Diesels usually have fewer wheels, so the axle load is greater on diesels (thus more adhesion).
Well, the only exception might be Kato FEF3 and GS-4 due to their intentional design of the driver suspension (where the TT-driver supports most of the locos weight). Those things are incredible. I guess that soon will will also see how Kato Big Boy is designed and pulls.
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Yes, unlike the prototype, a "huge" N Scale steam loco is not proportionally heavier than an F unit for its size. It's all about weight and wheel contact. So a big ol' Challenger with 12 driving wheels isn't necessarily going to pull as much as a 4-axle diesel. EXCEPT, in side that big Challenger body, you should be able to find some space for a lot of extra weight.
Do you happen to have a gram scale or postal scale of some kind? An old-school 1st-gen Kato F7 weighs about 125g, and one of those will pull 50 cars all on its own with no traction tires. How much does that Challenger loco weigh?
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Yes, unlike the prototype, a "huge" N Scale steam loco is not proportionally heavier than an F unit for its size. It's all about weight and wheel contact. So a big ol' Challenger with 12 driving wheels isn't necessarily going to pull as much as a 4-axle diesel. EXCEPT, in side that big Challenger body, you should be able to find some space for a lot of extra weight.
Do you happen to have a gram scale or postal scale of some kind? An old-school 1st-gen Kato F7 weighs about 125g, and one of those will pull 50 cars all on its own with no traction tires. How much does that Challenger loco weigh?
All good points Max. And the fact that an F unit, despite its shorter length, has a full width/full height body and a steam engine does not.
Yes, I do have a scale:
The Athearn Challenger weighs in at 6.5 oz/186 grams, the loco alone is 3.9/112 and tender 2.6/74
BLI F7, 2.7/79, BLI F3 2.6/76, KATO (new) 3.8/110
For comparison, the Kato UP 4-8-4 weighs in at 5.1 oz/144 grams, loco alone 3.6/103 and tender only 1.5/41
The Challenger tender is a bit on the heavy side, but that's where most of the electrical pickup is, six axles. The loco only picks up on three in each engine, and two of those have TT's.
Otto K.
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Well, even though 112 isn't terrible, I still say it needs to be a good bit more if you want it to climb hills with a long (i.e. say 30 car) train. That 112 is spread out over a lot of wheels, and it doesn't have the natty sprung equalized system that the Kato FEF has.
Is there enough room under the boiler shell to put metal plates all the way down the middle on top of the circuit board, with gaps where the motor and flywheels are? It would have to be tungsten and it could have a strip of Kapton tape on it so it won't short anything out. You could experiment with different thicknesses of styrene to figure out what thickness will fit, and then we can go hunt for tungsten pieces that size.
You put 14g on there and it helped, so I'm thinking if you could somewhere in the neighborhood of 25g on it, you'd reach your goal.
Try putting another 1/4 oz on top of the boiler over the FRONT engine truck, in addition to the 1/2 oz you had on the back.
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You could experiment with different thicknesses of styrene to figure out what thickness will fit, and then we can go hunt for tungsten pieces that size.
Here is a method I use to quickly gauge the amount of clearance under a shell: https://www.therailwire.net/forum/index.php?topic=55419.msg761385#msg761385 (https://www.therailwire.net/forum/index.php?topic=55419.msg761385#msg761385)
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could the motor not have good torque?
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could the motor not have good torque?
Well, a good question. So far, not an issue, just slips. But when close to maxed out with a load it's capable of handling, the loco does slow down on 18" curves and slightly steeper sections. I'll play with additional external weights, per Max, to see whether that's a concern.
Thanks, Otto
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On the motor, yes, let's all remember that the problem here isn't that the loco "stops" on hills or with a lot of cars.
It slips. So at present, this is purely a traction problem. Once we get it to stop slipping, if it actually slows down objectionably, then we have a new problem: not enough torque from the motor. But so far, it's never pulled enough cars to see that.
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If that weight test is favorable…
Maybe already in your head but tungsten putty works out to be similar density to lead
Particularly if space is limited as an alternate you can fit it in the nooks / crannies
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Max, as usual, you're right on. Time will tell, but I do sense that torque may become an issue with more weight. But first, I need to find a place to put it...
Jeff, I haven't yet tried additional external weight to test it, been busy. We had another op session today and even managed to run one of the Challengers with its full Pony Express train, but only westbound, downhill :facepalm: So for now, it's a one-way Pony...
As to adding weight to "nooks and crannies", there aren't too many of them, see diagram. Even the domes have weights in them, and a good chunk of the mech is taken up by the motor and flywheels. I'd be really interested to see where people add weight to these pups, so far no response to that question I asked earlier.
Otto
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The metal weights used in modern locos are not lead - they are made of lighter then lead zinc-based (white metal) alloy. My point is that if you were to replace the factory installed weights with lead or tungsten putty, you should be able to increase the loco's weight without finding any empty spaces to add weight. But if the only place this can be done is in the domes, then it is probably not worth the effort.
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What are 25 and 26 in the diagram? Are those the weights that go up in the domes? If so, how big are they and how much do they weigh? If they are just typical "white metal", they look big enough that replacing them with tungsten would be worth it.
I was more thinking about any air gap between the top of the circuit board and the inside of the boiler shell.
And what about right on top of the motor? Is there an air space there? Thin tungsten plates can really add up if you can stack
them in there. It also looks like you could stick some groups of tungsten cubes on top of the circuit board in the spaces between
the motor and the flywheels, and a long strip of little ones along each side right next to the motor.
While it hurts to give up the density of tungsten, sometimes a thin lead sheet is just easier to fit in there. If you could put in
a long narrow lead sheet (like 1/32" thick) formed up against the inside of the boiler, running all the way from front to back,
that could add a good bit of weight, and it would just come right off with the shell. Look for cavities where uniformly-shaped
weights can go - those are best suited to tungsten plates and cubes. Then go for things like inside of the boiler with thin
lead sheet.
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There is also the lead shot method to fill irregular cavities too. I still have 9 pounds of it.
You could make a silicone or JB weld mold of those two weights and cast your own lead replacements. The video of the mold is a wax melt-out, but the concept is the same.
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You widened those grooves? ROCK AND ROLL, man. That is a great solution, but like you said, not easy.
Did you do it in a lathe or did you use some home-brew scheme like running it on its back and carefully holding
files or a Dremel in there?
Are the traction tire drivers on the Challenger pinned to the rods? Or are they just geared with the rods running around
in front of them for show?
Sorry it took so long to get back to you guys, been a little bit busy lately. To answer a few questions, yes Max I took the drivers all apart, and chucked them into my dremel, the with a little tiny file and a lot of patience, (annd nervousness) I widen out the groove. One of the things I discovered is that the traction tires, as they came from the factory, we're way too close to flange and too narrow. They were only making a small amount of contact with the railhead. By widening Groove and putting a little bit taller Traction Tire on, I gained 20 cars. That also gave me an excuse to requarter everything. It does have a little bit of a wobble but I will take a small wobble over no traction.
If I remember correctly, the Traction tires are geared, but also pinned to the side rods.
We had a train show in Monroe Washington last weekend, and I ran the Challenger again, this time with my reefer string, and a special car right behind a locomotive, to prove that it's not going downhill!! :trollface: :trollface: :D I don't remember the exact count of cars but it's around 50 and a caboose. I actually threw his traction tire at this show, the first time since I have done this work. Luckily I caught it before it got wound up in the side rods! I was able to walk the traction tire back on with no issues, but I was ready to park the train at that point, it had been running for an hour and a half.