PRR H10 Remotor

[Cajonpassfan]

Well, at this point, I'm keeping my mouth shut and my eyes peeled
Otto

[victor miranda]

But the Atlas fix / "Bearden" fix  uses a shaft with a hex end on it, in a hex-shaped recess in the flywheel.
That means that at any point in the rotation, there are always 6 sides symmetrically pushing
on the shaft to keep it centered at that end.  With the two little ears, at any point in the rotation, the
shaft is held centered through one plane, but can  rotate on the axis of the ears in the other.   The other thing the Bearden fix
has is a real bearing on the other end of the worm shaft, not just a washer.  That bearing provides more length
for the shaft to go through, which helps keep the shaft from pivoting at that bearing.

The 2nd thrust washer with the bigger hole in it isn't going to really touch the shaft, if I understand this correctly.  It's
there to take up axial load, not keep the shaft aligned.

I suppose as long as the ball is firmly in the cup, it might work.
I fear the shaft is going to wing around like a jumprope being swung between two children.

copied due to page flip...

if that is a nwsl ball and cup, the fit is good and a little grease will make for a long life.
the fit is better than the Atlas hex, smoother, and quiet.
and the floppy issues exist in the atlas units...

you are quite correct that the parts need to be properly made
a close fit for the far bearing/thrust disk and the joint needs to be a close fit.


I do not see a need for the inner thrust disk.
the joint can transfer that thrust to the motor.
and that disk will cause noise problems

the drive train is not as I would set it up.
... and not as you would do,
yet I think it will work.

I need to get back to my ore jenny....
crown trucks are on the way.

(being a SPF for the day...)

and looking forward to this loco in DGLE.

victor
 
edited because I can't proof read... again

[nscaleSPF2]

So here is the new powertrain:

I suppose as long as the ball is firmly in the cup, it might work.
I fear the shaft is going to wing around like a jumprope being swung between two children.

Max, you can relax now.  Not only does it work, it seems to run very smoothly.  In spite of the fact that I tried to Loctite the motor shaft to one of its bearings.  I think the motor is ok, now.  We'll see how it works when all of the drivers and running gear are installed.

I would do two bearing washers and a dogbone (with the two matching cups)
I like thrust on bearing blocks, not motors.
the dogbone solution takes up some more space ...

Victor, it would have been nice to have a dogbone, I agree.  But fitting it in this space would have been tight, even if one were to shorten the worm gear.

Are you sure you got the right part? (Pete is referring to the cup/coupler) 0.047" is 1.20mm (Minitrix motors use that size shafts) while 0.059" is 1.50mm (more standard size shaft).   Sounds like the part you bought is designed for the 1.20mm shaft.

Pete, according to "Dave" at NWSL, I did get the right part.  He claims that the .047" i.d. Will press over the .059" o.d. all day long.  I was skeptical, so I got a piece of s/s tubing 2.0mm o.d. X 1.5mm i.d., pressed it into a 2.0mm i.d. cup that came in the NWSL kit, and then Loctited the tube onto the motor shaft.  (Note to self:  don't press it on too far, or, well, see above).

P.S. be sure and adjust the eccentric crank.

Holy c***, Jason.  I didn't notice that before.  I wonder how long it's been like that.

Stay tuned for more updates, forumers....

[Kisatchie]

P.S. be sure and adjust the eccentric crank.

Hmm... Kiz is an eccentric
crank...

[mmagliaro]

Looks great, man.  I'm glad it worked out after all!

[strummer]

Stay tuned for more updates, forumers....

Am looking forward to them...

Mark in Oregon

[peteski]

Sweet!

[nscaleSPF2]

TCS Z2 decoder installed. 
I should mention that I removed the rear thrust washer from the worm shaft.  It made noise, as Victor predicted. 
The extra wires are for the headlight LED, which will point upward at a very short optic cable, which is threaded thru the headlight casting.



An improved side view.  The boiler has been straightened, but it's a little low in the front.



The motor still sticks out a little from the rear of the cab, but not nearly as much.



In case you were thinking that this project is almost done, let me tell you what else went wrong.

I applied track power to the loco's frame and got the drivers to turn.  A little stiff, but not too bad.  Noticed some wobble in the #2 driver set.
Then I placed the loco onto the track.  This is where the problems started.
The wobble that I noticed prevented all of drivers from contacting the track at the same time.  Result is that there is almost no electrical contact coming from any of the loco's drivers.

Closer inspection of the #2 driver revealed that the plastic face is cracked, as if a too-large pin was inserted into the face.  This, in spite of the fact that this driver is not attached to the main rod.  I know, this doesn't make sense.  This unit was apparent repaired before I got it, in spite of the fact that I bought it new, from a very reputable dealer.  The screw that held the two halves of the frame probably went missing at the same time.

So I plan to replace the defective driver, along with the rods and valve gear if I can get them.  Oh yeah, the pins that attach the rods to the #3 drivers are not exactly straight, either.  This can't be helping.

The saga continues...

[Chris333]

Don't know if it matters with the other problems, but you have one rod installed wrong.

[peteski]

That kind of jumps out at ya, doesn't it?   

[nscaleSPF2]

Don't know if it matters with the other problems, but you have one rod installed wrong.

Oops.  Looks like the rod on the other side is wrong, too.  Thanks, Chris.

[nscaleSPF2]

Received a set of drivers, cylinders, and valve gear from Bachmann.  The drivers, however, are quartered 180 degrees opposite from the drivers currently on the loco, so they are not interchangeable.  A call to the Bachmann parts department revealed that they were unaware of the new quartering scheme.

So this left me with 3 options that I could think of:
A.  Replace all the drivers, meaning that I would throw away 3 perfectly good ones.
B.  Try to re-quarter the #2 driver.  (The probability of me being successful with this is less than 1%).
C.  Use the parts on the loco and try to make them work.  (Using all of the new parts as spares).

I chose C. 

I scraped a tiny amount from the top of the #2 bearing pocket in the frame; this prevented the #2 driver from "jacking up" the left side of the loco.  This seemed to improve electrical contact.  I also experimented with the torque on the fasteners that hold the motor and the lower plate to the frame.

Performance is not perfect, but the loco runs very quietly, and reasonably smoothly at low speed.  Should run a little better after break-in.

This episode has left me more than a little disenchanted with Bachmann steamers.  The first couple of people that I talked to in the Bachmann parts department did not know what the term "quartering" meant.  I have a couple of other Bachmanns, and they don't run that well, either.  Which is too bad, because I have another nice Jason Smith boiler shell that I was thinking of using on the 2-10-2 chassis to make a PRR N2 steamer.  Oh, well.  We do the best we can.

Next steps:  Add weight to the inside of the boiler, add details to the exterior of the boiler.  More pictures, when that part is done.

[mmagliaro]

Try not to be too disenchanted with Bachmann.
I consider them very valuable even though I have a love/hate opinion of them.

Generally, my experiences calling their parts department are equal to yours (meaning they are
fairly hapless and don't really understand the models they are servicing).
I also have never started with a Bachmann engine for a kitbash or scratchbuild project, because, well,
if I am going to modify and bash, I am going to have to make changes anyway, and there are better-built
engine chassis out there.

So why do I consider them valuable?  Because for all their faults, they keep trying to make new American prototype steam locos and nobody else is really doing that.   Kato and Athearn have done a scant few, but nothing
on the scale of what Bachmann is trying to do. 

I also consider them to be a valuable source of parts. 

So I don't want them to quit trying.   If they ever get it right, I will buy.

[PiperguyUMD]

What a cool project!  Looks like I will need to revamp my shapeways H10!  Can you compile a final parts list?  Aside from the driver issues, do you think this is something that could improve all Bachmann 2-8-0s?

[victor miranda]

piperguy,
I would like to have one of what you have done thus far.

I have a different motor in mind but the idea is otherwise much the same.

I have almost purchased your tender and cab... many times.
I don't mind if you improve it, buuuut I need to have something to see the fitting.

as an aside on the subject of modeling, you may want to stretch your shell a little.
this is to allow the slightly for the larger flanges of n-scale.
my off hand guess is the shell from steamchest to cab needs about 1.5 mm to 2 mm more.

.
victor