Best Of The Overland/Wiseman brass Western Maryland Shay thread

[u18b]

Well that simplifies that part.   Depending on what else is there, maybe we could make it move.    It looks like it has a hub that it spins on.

Mark.... you brought this up twice with your curiosity and ingenuity.
That is (in my words).... "wouldn't if be cool if the valve lifter actually moved?"

Much to my astonishment, they DO move on the 1st version Shay!!! 
Not much, but you can see it.

As a set up... look again at this shot of the revised Shay.
There are three round guides on the crankshaft.  one is just to the right of the drive gear, the other two are next to the rings of the u-joints.
Notice they are much smaller when compared to the rings of the u-joint.



Now here is the 1st version.  The valve rod guide (or bearing if you like) appears larger- though that may be an illusion if the cast ring of the u-joint is smaller.
At any rate, the rocking piece up top is NOT soldered in place (as it is on the Wiseman Shay).  Instead, a bent wire holds it in place.   It is very floppy- by design, and it wiggles when the loco runs.  In fact, you can see the middle rocker is pretty loose and flopped up a bit.



Now I understand why OMI made the mounting support hole so large- so the rocker could wiggle.
The support wire goes through the rocker and that hole and is bent on both ends.
obviously, this would have to all be done in the assembly process.   Once the piston assembly is built, it would be hard to get behind those cylinders.



Here is the rocker casting. 
The pins on the back are the mounting pins for the lifting rods.
The long pin on the right is prototypical.  However, OMI cut those off during their assembly.
(By the way, I should mention that in my ignorance, I mounted mine backwards with the long pin going into the mounting hole.).



What I find curious is the back side.  That hole makes you think that the long top pin is pressed in- but it is not.  It's just a hole in the master and is cast that way.
however.... what would have happened in they had cast this piece with the hole and not top pin.   You could then insert a soft copper wire into the hole and carefully solder in place.   The solder would loke the pin on the front and then you could bend the wire in the rear inside the cylinder assembly.



Which valve rod assembly is better?   This wiggle is kind of cool, but it may be one more thing to go wrong.   The version with the rockers soldered in place might be better.

If anyone out there has a revised/recalled Shay in a green OMI box (hence one that is NOT a Wiseman Shay)... check it for me and see if your rockers wiggle or are soldered in place.

[narrowminded]

Hi Ron,

I would probably machine all of those bits.  To do this there would be lots of unseen little fixturing, gripping tools made to accurately position and machine all of the pieces.  Castings when this small are dimensionally suspect to begin with, material potentially flawed, and near impossible to accurately and repeatedly position and machine.  For any chance at reliable performance tolerances of less than .001" are all over a mechanism like this.  I suspect that for the most part really good fits with Loctite would be used in lieu of a lot of the soldered joints.  Thought out fixtures for machining and assembly and micro tools, existing or specifically ground for the job can machine pretty accurately and repeatedly, therefore fits and alignments improve, therefore the mechanism has a better chance of running smoothly and reliably.  I'd still need to give a good look at the pieces to determine feasibility but I suspect it can be done.

And on the eccentrics, I figured that those small grooved/ double flanged pieces shown next to one of the crank throws were the eccentrics.  Until I see the parts I don't know if it can be done this way but, I would consider machining those as one piece to the adjacent crank throw to afford a longer engagement/ support for the crank journal stability.  Things like that would all be weighed in the feasibility and methods chosen for all aspects of the project.  It would be an interesting challenge to do this.  Looking at it, maybe we should consider redoing the universal joints and gear shafts, too.

[u18b]

Hi Mark,
I'm just about ready to mail you a bag of parts.

I have your address.
I'll get them out this week.

[narrowminded]

Hi Mark,
I'm just about ready to mail you a bag of parts.

I have your address.
I'll get them out this week.

That sounds good!  The parts specific to the crankshaft will obviously be needed but any related or near related parts might prove handy too if only to grasp how these new parts will relate.  I'm thinking of those valve gear pieces, too.  It may not be too hard to make those work.

Please understand that I am up to my eyeballs in turnout and track fixtures right now (machining this week and probably into next week) so this won't be able to happen right away.  On receipt, I will at least try to get a good look at the pieces and start figuring how it might be done.  I suspect there will be a few questions as we go.  This will be a challenging, yet fun project.   Looking forward to receiving those parts.

[u18b]

To add to the record.
Here is a better shot of one of the delicate shafts.  This one is on the tender.

[u18b]

And now it's time to take the shell off of this version 1 Shay.



The drive train is very different from the version 2.
The motor is a fairly small Sagami closed can motor.  It is screwed to a motor mount.


The motor has a brass u-joint half mounted to the shaft.


The worm shaft has an old school u-joint half.  These were common in the 60s-late 80s.



Notice that hunk of lead is designed to keep that power truck on the rails.
There is a lot of wasted space because that u-joint is so long.
If this were my loco, I would explore installing a small coreless motor with a gearhead on it.
That would slow this thing down- since now it runs 95 scale MPH (the prototype ran at 6-7 mph).



Because of that lead weight, it's hard to photograph the worm.  This is the inboard view looking over the motor.
The worm is on the right.   The transition gear is on the left.  The transition gear looks like it could be removed once the set screw is loosened.
I assume you could then drop the perpendicular drive shaft out.



Here is an outboard view looking from the tender.  Note the worm bearings are plastic.   If run, these would need to be well lubricated to avoid excess wear.

[u18b]

On a minor note, I noticed they cut a slot in the firebox for the wire from the front truck.

[u18b]

How does this Shay run?

Answer - mixed.

Overall, it runs fairly well at a speed that is way too fast.
When you slow it down, it is not as reliable.  This could be improved by adding a pick-up wire and contacts to the tender truck.

But this Shay also derailed on a spot on my test track that is slightly uneven.  On that spot, the torque of the perpendicular drive shaft would twist the truck and the leading wheel of the rear truck would lift over the railhead and derail the loco.

But I noticed that the cast drawbar was bent upward too much (you can see it in this photo).
So I bent it downward a little.



This had two effects- one good and one not good.
On the good side, it leveled out the tender- and I noticed the cab truck no longer derailed as much at that one spot on my track.  This means that the tender may be a contributing factor to that derailing issue.

So derailing reduction was good.
But..... lowering the drawbar even slightly, has the effect of lowering the back end of the tender.
And when that happened, the steps become dangerously low to the track with inevitable electrical shorting.


I thus conclude that if I was going to run this a lot, an extra washer would be needed to raise the tender body off its truck.
Or I could shim the drawbar.

[Chris333]

I have a HOn30 12 ton class A Climax from NWSL and when searching online I see there was an early drive version of it as well. Wonder why they didn't just do it right to begin with.

[u18b]

After a little more testing, I confirm my old memory that these 1st version Shays are frustrating.

I had a derailment and took a photo before moving it.


I'm thinking now that one problem (besides torque) is that there is just too much play in this truck.

If this were my Shay, I'd take it apart and put scores of hours into it to solve this problem.  I'm guessing that the truck-to-bolster interface needs a shim (thin washer) to make it a bit tighter.  Remember, there is no screw that you can tighten or shim.  The drive shaft itself holds the truck in place.

But this is only a loaner to me, and the owner does not really use this as a runner.  Consequently, I'm going to have to stop here.
As long as this truck has this much play in it, derailments are going to be par for the course.

These derailments are what I remember from my experience from my first Shay almost 30 years ago.
(and I STILL just loved this way-cool locomotive).

[u18b]

One other thing you could do is weight the body shell.
After all, the boiler is a hollow tube with detail wires sticking into it.



Since it is sealed, you could pour a low-temp alloy into it.
Walthers used to sell one called "Temp-Lo".  Because the melting point is low, you won't damage the existing solder.
But you can still buy that stuff coming in different names.  I bought this off of ebay.
I also bought a brick of "cerrolow"
(some of this stuff is toxic- watch out).



If some was melted, you could fill up the boiler.



Maybe the extra weight would help tracking.

[Chris333]

Think that stuff is called Cerrobend. I have a hugh brick of it.

[u18b]

Yes, I remember seeing that name too Chris.
You can find some on ebay by that name.
I also bought an ingot.

There are actually many alloys in this range.   Aside from specific ingredients, they also often go by their melting temp.
The one shown in the photo above melts at 136 degrees F.    Another alloy melts at 117 degrees- which is too low since sometimes a locomotive  can get a little warm!

The 136 stuff above is actually hard, does not bend easily.  I chose this alloy when I poured some of my own gear boxes for brass Kumata locomotives.   As long as the loco didn't get too warm, this was safe.

Cerrobend melts at 158, but is a bit soft- thus not as good for gearboxes.

I saw a chart somewhere on the different alloys, their melting point, and their hardness.

[u18b]

As I am wrapping up working on this first version Shay....


I think I'm coming to a new conclusion about another contributing factor for derailment.
Look at the side rod connection point between the tender and the cab.
I think both the male and female portions are both trimmed too short.
It is hard to completely tell from this photo, but I assure you that the rod is almost at it's edge in that socket- and this is straight.


Remember, this loco was made in 1989 and N scale was still stuck in the awful standard of 9 3/4" radius turns.   My assumption is that they had to trim these parts in order for this loco to make it around a tight curve like that.

I think what's happening is that as the loco is coming out of a left turn (where the rod is barely in its socket) AND the loco hits an uneven spot in the track, that's where the rod may partially jam in the socket and unduly help twist the cab truck.

So once again, if this were my Shay, I'd have to find a way to lengthen the rod in the tender driveline.

[u18b]

Maybe this is a better way to show what I mean.
This is an 11" radius curve (not even 9 3/4"!)
I've intentionally left the coupling disconnected.


Now here is a close up shot of the same placement.  With your imagination, you can see if that rod were inserted in that socket, it would barely be in there.


In a more practical description, what brought this to my attention was repeatedly placing this loco on the tracks.  Even while holding everything straight, it is almost IMPOSSIBLE to get this loco on the tracks on the first try without the tender shaft coupling coming un-done.
You almost need a railer to force this joint to stay in alignment.

Not good.