Best Of The Overland/Wiseman brass Western Maryland Shay thread

[u18b]

While I have not been commenting, I am closely following this thread in awe!

The construction of that engine is simlar to any 4-stroke internal combustion engine used in automobiles.  The rickers and "eccentric blades" are part of the valve gear.

The eccentric on the crankshaft would be equivalent to lobes on a camshaft, the blades would be like pushrods, and the rockers would be similar to rockers in automobile engines.  What is amazing is that all this detail was all modeled, and operational, on an N scale model!

That was my thinking as well.
But I didn't want to use terminology that was wrong.

Here is a video where you can see this part at work.  Skip to about 1:30 for a slow driveby.
You can see the eccentric bearings raise and lower the blades, but the prototype does something else.  The rocker itself not only rocks side to side but also raises and lowers and actuates a smaller piston above it.

Here is another video. Short.... and a bit less professional, but shows the action we're talking about pretty well.

[Chris333]

Same thing as a regular locomotive except they are hidden horizontal between the frame rails.

http://mikes.railhistory.railfan.net/r132.html

They time the steam inlet and exhaust from the cylinder.

A HOn30 shay I had only used one etching per side because of space. and the top just hooked onto something to hold it still.
https://photos.app.goo.gl/D8PDEC3xAaPb3ys98

[u18b]

Thanks for posting that Chris.
What an amazing model.

[u18b]

Crankshaft Almost Finished

I decided I wanted to be able to remove my crankshaft assembly in the future- not only for repairs, but also for painting.  Since you cannot spin the crankshaft the way Wiseman installed it….. when everything is soldered together- how do you fully paint the crankshaft parts?

On the other hand, if I can remove the entire crankshaft assembly, then painting will be a breeze.

Consequently, the rockers needed to NOT be soldered permanently.

I noticed the rocker casting had a small depression in the center.  I decided to drill this out- and thus the long shaft on the back of the rocker would be lost.

   

A steady hand and very tiny drill bit were required.




My plan was to run a retaining wire through all of the rockers.

With the hole drilled, I trimmed the outer rocker pins, and I soldered the rocker onto the two eccentric blades I had already installed on the crankshaft.  It was a tricky soldering job.  This piece is tiny.  I needed the extra hands of a soldering station with alligator clips.




Here is the whole assembly so far.   This is the part that goes inside the cylinder assembly housing.   The only thing missing is the Atlas thrust washers on the ends.



I made two more bearing/eccentric blades/rocker assemblies and installed them on the crankshaft.    I then test-ran a wire (.008” guitar string) through them all.



Later on, I’ll replace that stiff and hard guitar string with some .008” brass wire.

[u18b]

Crankshaft Assembly Completion

I’m now almost ready to install the crankshaft assembly.  But first I need to install the base for the universal joints.   The base looks like little footballs or barrels in the revised Shays.

The first run Shay employed tiny and very delicate forks onto the driveshaft.   But this barrel is MUCH better.  It is beefier and can take the stresses much better.

These barrels seal off all the parts on the crankshaft and along with the U-joint will complete the crankshaft assembly as one unit.



The photo below is part of a universal joint-- though we don’t need that square shaft in this photo.  This is a universal joint from a truck, but it shows how the barrel works.

As shown in the diagram on page 9, the universal joints are part of the line shaft system on a Shay.



As with other parts, I discovered the stock hole on the barrel was for a smaller shaft.  I therefore carefully had to drill the barrels out for a 3/64” shaft.  Here is a test fit. 

This one needs just a little more reaming so that the crankshaft comes all the way to the end.

I confess I was worried the walls of the barrel were getting a bit thin, but it worked out in the end.



I cut the crankshaft excess using my other Shay as a guide. 
I measured the other shay- though the measurement is a little bit imprecise since the spot I want is inside the universal joint.

My cut crankshaft ended up being 20mm.  In retrospect, 21mm or 22mm might have been better to give just a TINY bit more good fit for the sleeves and square shafts.  If the joint is too short, then the square shaft will come out of the sleeve.

But 20mm works and should be considered the minimum from end to end. I’ll save this number for future reference since I will be rebuilding another Shay one day.

I installed the barrels for the u-joints and soldered them in place.  This is now the entire crankshaft assembly.  It will be retained by two bearing retainers to be added later to the cylinder assembly frame.

The eccentric blades and rockers will be retained by the thin wire that runs through the rockers and cylinders at the top.
Thus, in the future, this whole assembly could be removed for painting or for maintenance/repair.

I think my solution is a definite improvement over my other two Shays- and even Overland’s original design.

[u18b]

Crankshaft Installation

I carefully lowered the crankshaft assembly into place in the cylinder assembly.  The middle eccentric blades/rocker combo have to go through a slot in the cylinder assembly at the middle cylinder which is a bit of a tight fit- so I had to be careful.

I temporarily installed a thin wire up top to hold the assembly in place.



In the view from below.  Notice the white Atlas thrust washers are just inside the cylinder assembly housing.

The crankshaft retainers will fit in the gaps and be soldered to the main bearing (but not the shaft!)




Here are the crankshaft retainers which were removed from the old Shay.  One is still pretty dirty, the other is being cleaned up.  Notice they are not symmetrical.

They are also pretty simple and I could make more if needed.




The skinny part goes to the outside.  You can see this from the shot of the main bearings.    Skinny side yellow, thick side blue.





The retainers were installed with just a little solder to hold them in place.

With the cylinder worm in place with its head gear temporarily installed, I was able to spin the crankshaft assembly by hand looking for catches, cogs and any roughness.  I’m looking for smoothness in every way.

So far so good.

In the future, when I want to drop the crankshaft assembly for painting, I’ll snip the copper wire running through the rockers and then unsolder the crankshaft retainers.

The whole crankshaft assembly will then be able to be dropped out.

Making progress!

The only thing left in this area is to add the universal joints with sleeves.

[u18b]

Universal Joints

I then turned to the u-joints.   The barrel was installed.   I should have mentioned before that I was careful to install the barrel perpendicular to the crankshaft- otherwise wobble would be introduced when running.

Now I need the line shaft sleeves installed on each end with its ring.
 
The crankshaft has sleeves.  The trucks have square shafts (although the truck under the cab has both).

The WM Shay follows the same pattern as in this drawing.  The crankshaft has sleeve shafts attached on each end.  The square shafts are located on the trucks.




I should add that the barrel system I’m using here is part of the revised/2nd versions Shays.    As released, the line shaft parts used cast parts which were VERY delicate- and often broke as seen here in this photo.   I am NOT using these parts.  You can tell this is a cast part because it has a 3-d effect.  It looks more prototypical, but I’ll take stronger in this case.




The stronger ring is just a piece of curved metal with four holes.   Here is a disassembled universal from a truck.



You have to bend the ring a bit to disassemble the u-joint.  And then bend it back when putting it all together.

Honestly, it is tricky to get it done.  And of course you want it all round when you are finished.  If it is not round, the eccentric wobble of the universal joint will be noticeable when the loco runs.

Here is the completed assembly. 


I then add a TINY bit of solder to the joint of the ring to lock the ring in place to keep it from bending (and to hide the gap).  I obviously don’t want to get solder inside the universal joint inner workings or pivot posts.

In this shot (from another Shay), you can see an unsoldered joint (red) and a joint that has been soldered (blue on the top side).



I then go back and file off the excess solder to clean it all up.



And here is a shot of all the parts in the final crankshaft assembly.
What you see is (with color coding):
u-joint- blue
eccentric blades and bearing- yellow
crankshaft retainer- red
main bearing- green (the solder joint of the main bearing and the retainer is between the red and green lines.  I only soldered one end)
Atlas thrust washer- purple



Whew.   This was the main task in this reconstruction.  The frame transplant is complete.
It was a lot of work to get to this point.

I can now begin to turn my attention to getting this mechanism to run.

[u18b]

Motor and Worm

Time to start making this Shay run!

The first step was to  temporarily install the front and rear trucks. 

With the lower crankshaft worm removed, I was able to place the chassis on the track and move the chassis back and forth by hand- looking for any catches, or any cogging, binding or hesitation.  All felt smooth and good.

Thankfully, I am not having to rebuild any trucks. (That process is covered earlier in this thread.)  However, I did need to tweak and tune them a little bit.  I’ll talk more about that in the future.

With a smooth running mechanism, it was then time to permanently install the lower crankshaft worm and then solder the cylinder head gear onto the shaft.  The cylinder head gear (as I’m calling it)  is the one recessed inside the cylinder.  You solder the tip of the shaft at the top of the gear.



I now turn my attention to the motor and the worm.
In the stock configuration, there is a large bushing installed on the worm shaft.
The motor and the worm shaft are connected by a rubber tube.

You can see the stock configuration in the “before” photo of the dead Shay.



My experience is that this configuration is ill-conceived and is in fact a disaster in the brass Shay. 

The wormshaft is 1mm, the motor shaft is 1.5mm and the bushing is about 2mm.  The end result is that the motor end of the equation slips because the tube stretched to 2 mm cannot compensate well down to 1.5mm!

In the photo above of  the dead Shay, when the motor was unscrewed from the frame, the motor shaft easily slid out of that tube.    There was no grip at all.

Another problem I have commonly seen is that the rubber tube over the   2mm bushing does not clear the floor of the motor frame very well.  The tube can scrape the floor of the motor mount plate.   This creates friction and can induce shaft wobble too.

I want to replace ALL of this mess.

The first step was to get the bushing off of the worm shaft.  It is soldered on.  I heated it with the resistance soldering station.



I then cut a small length of some transition tubing to take the worm shaft from 1mm to 1.5mm.  It is held on by a spot of superglue.

With this change, now the motor and the worm shafts match at 1.5mm.



I then like to use the u-joints from an old Atlas/Kato ALCO RS-3 (and also found in the old out of scale Kato GP7/9).  Man, I love these joints.  They are very helpful.   But they are long gone.   I like them so much I have actually stolen them from some old extra chassis I had lying around.

(If anyone has any extra u-joints, I’d be willing to buy them).

The rear motor shaft has been trimmed short with the edges rounded.  Sharp edges might cut wires and cause shorts.

Here is everything installed.  Please note how I used a motor tool and rounded out the motor mount base under the u-joints in order to give more clearance.



A little quick soldering of motor connections and now for a test run.
Yay! We have life!  A running Shay is in my future.

It doesn’t run as great as I want- but that’s OK at this point.   The goal here was just to get it running.



It has taken a LOT of time to get to this point…. And a lot of time still to go.   But I’m very encouraged.

[davefoxx]

Ron,

I can't tell how well it runs without video, but I sure can say it already looks 100% better.

Kudos,
DFF

[u18b]

Thanks Dave. 
It’s too loud and it’s unreliable. 
So I’ve got a long way to go.

But I’ve tinkered and adjusted these Shays before.  It will possibly take many hours, but it’s familiar territory. 

But doing a frame swap and making some design changes was uncharted waters.
I’m glad that’s behind me. 

And while not satisfactory yet, this Shay is already better than I feared when I started.

[u18b]

More Motor Area

Now, at present, the motor mount base plate is only retained by the upper worm gear screw (the worm gear is the transition gear between the worm and the cylinder head gear). 

Normally, this motor mount base piece would be soldered to the chassis, but I really REALLY like the modular approach.  I take things apart a lot- especially while building and tinkering.  So if I can make this modular- all the better.

Consequently, I drilled three extra holes for the new motor frame base mounting screws (the black screws in the shot below).

The motor mount plate holes were enlarged so these new screws will pass through.   

On the lower chassis frame plate, the holes were then tapped and threaded for the new screws (M1.4). 



I then installed a TCS micro plug and socket.  While I’m going to place a 2-pin plug on the motor lead,  I used a 4-pin socket because it is much stronger than the 2-pin socket.

The socket went onto a little copper clad board- and the board is superglued to the frame.  This board is for the insulated wires.  The board has to be placed in such a way that it is away from the cab wall of body shell when put in place.  Remember that the shell and frame are all electrically charged and not insulated (typical of most brass locos).  This pad is for the insulated side.

The truck wires from the insulated truck wheels are soldered here to the back of this pad.



A plug is installed on one of the motor leads.  I experimented as to polarity so that the loco goes in the same direction in analog mode as other locos.



The other motor lead goes to the frame.  But I want to be modular.  So I made a tab.  The wire is soldered to the tab.   The tab is secured by the motor screw.

The tab is actually one of the piston rods.  Since I’m not using them in the pistons, then this seemed like a good use.



Now we are modular!  I can assemble and disassemble this mechanism all day long without having to solder anything.



And I’m sure I have a lot of cycles of disassembly and reassembly ahead of me.

[u18b]

Correcting Some Problems

The resurrected Shay runs…. which is really satisfying compared to where this project began.

But there were some serious problems.   The Shay was noticeably leaning to the left.  It was also not running reliably.

First, the power reverse on the right side under the cab is an obstruction.
I have seen this on other Shays and I consider this a design flaw.

In this photo of another Shay from years ago, you can see the top of the truck sideframe hits the bottom side of the power reverse detail.   The same was happening with this Shay.




If this is not corrected, there is only one other solution- and that is to add shims to the bolster and raise the body away from the truck.  But when that is done, it makes the lineshafts no longer be “in a line”.  Look at this photo from years ago on a previous Shay and see how uneven the linshafts have become.



I chose to correct this problem on this Shay.   I removed the rear truck and then removed the power reverse with the resistance soldering station.

Part of the problem is that the power reverse detail itself is too tall.
The mounting portion up top can be shaved down a little with a cut-off wheel and a motor tool.  Here is a stock piece.  Once trimmed, it can ride higher away from the truck and closer to the floor of the cab.



But it turns out the mounting bracket itself is also an obstruction!  This photo just astounds me!  Did no one at Overland and M.S. Models of Korea see this as a problem?  Look at how the truck’s top surface is actually riding right on the right side of that mounting bracket.



I trimmed the excess from the bracket, cut the slot deeper so the detail could be moved higher (away from the truck).  I also trimmed the base of the bracket so that it could be moved closed to the frame.   

I then resoldered all of this back to the frame.

Studying photos of the prototype, I concluded the power reverse should be more forward and deeper than OMI’s placement.

Compare this photo by Bob Vogel of the Shay at Cass Scenic Railroad….

http://www.rrpicturearchives.net/showPicture.aspx?id=2073449

And this photo of the stock Overland placement.

 

You can see the OMI placement was poor.  The power reverse sticks out MUCH too far on the N scale model.  It should be recessed up under the can more.

After correcting, this is now a much better look and the obstruction with the truck is gone. There is a slightly larger gap in the back and the power reverse is much more away from the outside edge.  I think this looks much better.  The model definitely runs better.



(I now have to do this to my other Shay’s one day!).

[u18b]

Another Problem

Another problem I discovered was in installing the screw which retains the truck under the cab. 
The T-nut in the bolster is threaded, but the frame opening inside the motor well is not.

I determined the pass thru area in the frame in the motor well was not big enough.  It placed a bind on the screw.

So I carefully used the motor tool to open up the hole on one end- without damaging the bolster screw hole underneath.

Here is the before photograph--



And here you can see the hole opened up.  The screw is not so tight now.  (sorry the photos are not oriented the same way)



The jury is out on whether I’ve helped or hurt by opening this hole so the screw is not so tight.  One possibility is that the hole was designed to be tight intentionally so that the screw would be retained whether seated or not.   But if you have seen stripped heads from owners using flat blade screwdrivers trying to get this screw out, you would understand why I did it.

However…. Even after correcting the power reverse problem, the rear truck was still leaning- not only side to side, but also from front to back.

I determined that the rear bolster under the cab was not just right.   I would run the loco for a few hours.  And then disassemble it and notice the wear marks on the bolster to truck interface were not even.  Clearly the truck was tilted- even if not very much.


I’m not sure if the problem is the truck, the frame or the bolster.   Maybe it was an assembly imperfection.  But I wanted that truck to sit flat.

Here is a shot of the bolsters for the trucks.



(The secondary hole that you see below the screw hole is for a little pin on the truck to restrict the pivot.)

The bolster is composed of a flat plate and a threaded T-nut.

Here is the front bolster I harvested from the old damaged frame.
The T-nut is taller on the front and shorter on the rear.



Here is the T-nut from the rear.



 

With resistance soldering, I was able to reposition all of these parts to get a placement where all the wheels touched equally. 

I’m not sure what the problem was, but I had to shim one corner  of the bolster with  .006” brass to lift one side and tilt it forward a bit.  It is possible that the problem was in the truck.

I have to admit, this was challenging and took a few attempts, but I was finally successful.  Everything sits much flatter now and all wheels touch the rails equally.

[u18b]

Miscellaneous

I then made the front truck wiring modular by installing a TCS micro plug and socket between the main body and the front truck.  This allows me to remove the front truck without a soldering iron.





Now it was time to clean up the cylinder area.

I removed the guitar string.
The small brass wire is then run through the tiny hole in each rocker.
I’m using .008” brass wire I bought in the beadwork/jewelry-making department of a craft store (like Hobby Lobby, Michael’s etc).



Here is a top view.




I then pulled it a little tight and trimmed the wire ends and bent them over the top toward the inside.  When all is painted black, they will not be very noticeable.



I then spent a LOT of time tinkering with this Shay mechanism to get it quieter.

I have two Shays that I have successfully gotten to be astonishingly quiet- but this one was a challenge.

I tried different motors, different spacer configurations.
I replaced the old worm bearings with new bearings and replaced the worm shaft as well as the worm.  I also adjusted the cylinder head gear.  This one paragraph represents hours and hours of tinkering.

Replacing the bearings helped.  I had an extra set.

I then Beardenized it by removing the inner bearing,  This helped a bit- which confirmed that part of the problem was worm bearings.



The sound level was better- but I’m still not satisfied.

I’ve ordered a new coreless motor- and that should be better.  This is the same motor I used in the Shay with sound described earlier in this thread.  It’s a great motor.  I buy them off ebay from a guy who goes by “tramfabriek” in the UK. 

I think part of the problem is the bearing and the worm shaft are not as tight as they could be (slop)- and this is a common problem in all my working with the brass Western Maryland Shay

The shaft itself seems to be made of a softer material.  You can easily solder to it and it can wear down.   In fact, I saw a Shay where this shaft actually had a groove worn into it.  I doubt this is made of hardened steel.

So I have ordered three drill bits with sizes differing by only a tiny amount.
(#59, #58, and #57).  When they come in, I will see how each of them fit as a replacement worm shaft.

The noise is not awful right now- but I want it to get better.  It’s acceptable, but not exactly quiet.    I’d love to get this model to “quiet” like my other two Shays.

More experimenting to come.

[u18b]

Sound As a Standard of Evaluation

There are many ways to evaluate a locomotive’s performance and have an indication that something is not right- or not as good as it could be.

I’ve always been impressed with Max @mmagliaro and the way he uses an amp meter to get an objective measurement of the performance.

Well, you can do that with sound as well- at least in a comparative way.

Of course, you instinctively make evaluations with your ear- it can tell you a lot.

But in this modern day and age, we have some new tools at our disposal that are more objective.

If you have a smart phone or watch, you probably can measure sound intensity.

I regret I don’t have a video of how this Shay first sounded when I got it all running.  But it was loud.

On my smart phone, I have a decibel app and I used it to get a reading on this loco and compare it to the other two Shays I have.

A free app for the iPhone is called Decibel X.  It has ads, but is free.  Here is what it looks like.

There is a histogram of individual frequencies.  The current real-time decibel reading is bottom-center.  The max is bottom right and is the number I look at.  Here is a screenshot of the ambient sound of my den.



I started the app and placed the phone so that the mic was near the track and ran the resurrected Shay at almost full throttle.   

The Shay was averaging a decibel reading in the upper 80s- which is REALLY loud.
The other two Shays were giving readings in the upper 60s at full throttle.

Now, the decibel reading measured is not what YOU hear because the mic on the phone is one inch from the track-  your ear is two or three feet from the loco.  What I’m interested in is the RELATIVE measure.  I’ve got two Shays that are quiet and this one is LOUD.

So after the tinkering of the previous post, I used two devices.   I measured sound with my Apple Watch 6 and I used my phone to record the whole thing.

To get a true measure, I experimented with each Shay to get the scale speed as exact as I could between the Shays using a scale speed device (Accutrak II- I love that thing.  Very helpful).

I then prepared the following video evaluation (2.5 minutes).

Same speed, same Apple watch measuring sound, same distance to the track.   Thus the comparisons are helpful and valid.

Before tinkering, the new Shay was off the charts loud.    Now it is tolerably loud- but I’m shooting for better.

This now gives me something specific to go by and measure against as I continue working on this new resurrected Shay.