Seeking 40 or 42 inch N Scale wheelsets

[mmagliaro]

Tony, that's great news!    I won't put you through the trouble to mail them.  I can get some from Bachmann when I order another stash of parts from them.    I really appreciate you digging around and measuring.  I was wondering about
the Con-Cor 4-6-4 trailing truck wheels just today.  I hadn't gotten to checking them.
But if the Bachmann Northern measures that close, that's great.

[LV LOU]

Max,found a TRIX diesel wheelset,it's .272..and I have 2 sets on a Con Cor Hudson trailing truck,they're .268..

[LV LOU]

Actually,now that I reallylook at them,they might be Bachmann Northern wheels off a really old one....

[Cajonpassfan]

I need 40" -42" wheels also for steam trailing trucks. The Bachmann is very wide, the cc Hudson little better. Wish I could find something with a finer thread....
Otto

[LV LOU]

 The TRIX diesel wheels look pretty good.Much narrower..

[mmagliaro]

To close the loop on this, I ended up using  "Bare Conductive" brand Paint to get one side live on the existing wheels.
It works much better than I thought it would.   When wet, it doesn't seem to conduct for squat.   But once it dries,
there no denying, it works.  I can touch leads to a pilot wheel and the tender, and the engine runs just fine.
Photos show how I modified the pilot wheelsets so that the paint will be able to be on the axle, and on the wheel,
and all around the edge of the new brass washer, without ever coming in contact with the truck frame, which could chip it off.

A tube of the stuff only costs about $10 at Radio Shack.  It is not silver-based.  It is carbon based.  But it works.

[Cajonpassfan]

Max, so whose wheelsets did you end up using? I must have missed it. The profile looks pretty good...
Otto

[mmagliaro]

Max, so whose wheelsets did you end up using? I must have missed it. The profile looks pretty good...
Otto

Those are the original wheelsets that were in the Key / Yulim 4-8-4 I was repairing.  I used the brass washers and
conductive paint to convert them from being insulated on both sides to having pickup on one side.  So I did not
need to change them out after all.  I thought I would have to, which is what caused me to open this thread
looking for a replacement.

[Lemosteam]

Max, what conducts the electricity from the now-conductive wheel?

[Cajonpassfan]

Max, got it, thanks.
That still leaves me looking for fine profile wheels for an inside bearing trailing truck, where the wheel is fully exposed...
Regards, Otto

[peteski]

Max, got it, thanks.
That still leaves me looking for fine profile wheels for an inside bearing trailing truck, where the wheel is fully exposed...
Regards, Otto

Otto,  you have a steam loco with such a large (42")  wheels in the trailing truck with inside bearings?  Which locomotive is it? I don't ever recall seeing a US prototype loco with that type of a trailing trucks.  I only see such arrangement on European steamers (and the wheels are spoked).

Lemosteam: since Max's model is brass, all the parts of the truck frame and loco frame (and the screws) conduct electricity. It might not be the most reliable connection but it is better than nothing at all. Maybe Max will solder a piece of flexible wire between the trailing truck and the frame for better connectivity.

Max: why couldn't you just replace the nylon insulating bushing with one made of brass?  Even if you couldn't machine one with tolerances tight enough for tight press fit, you could have soldered the wheel, bushing, and the axle. That would have resulted in a solid connection (both mechanical and electrical).

EDIT: spelling 

[mmagliaro]

The current flows from the wheel, through the conductive goo, to the axle.  The brass washer just reenforces the connection
and protects the goo coating.  As Peteski pointed out, everything is brass.  So current flows from the axle to the truck frame to
the main frame.
No, it certainly is not a "reliable" connection.  But it's better than you'd think.  There is enough weight on the truck to keep
positive contact between the axle and the truck frame.  The only flakey part is where the truck attaches to the main frame
with a screw.

But Peteski was right when he said, "It's better than nothing".  Even if,  from the whole pilot truck, you get a complete circuit only 50%
of the time, that is huge when you are battling the odds against a potential stall.  Even 30%.  Heck, that means that 1/3 of the time,
ALL the drivers and ALL the extra pickups on the tender wheels (which I added) can fail, and the the engine will still run.  Those are pretty good odds.

It looks like this when it runs now:  (and from what I'm told about this engine, they were all pretty awful).
It ain't no "Kato Mikado smooth", but it ain't bad.

http://www.youtube.com/watch?v=TROhW_lQG98

[Lemosteam]

LOL  "ain't bad".  Shessh your "ain't bad" is my "flawless".  Really nice improvement.  No motor changes?

[mmagliaro]

LOL  "ain't bad".  Shessh your "ain't bad" is my "flawless".  Really nice improvement.  No motor changes?

Thanks, John!   No, no motor changes.  I was doing this for a customer and trying not to escalate it into something that would
take me 50 hours and a fortune to build.   The long drive shaft on the motor in that engine means that you
either have to:
-  make a separate worm carrier with its own bearings, and connect that to a new motor with a U-joint or rubber tube
(EBIT fixes his that way)
- get a REALLY long motor, and even then, mount it on a new bracket closer to the worm

And even after you do that, I'm not so sure it will help that much because the mechanism itself it pretty
balky. 

Either option takes a lot of work and money.   I was able to simply tune the motor mount and stiffen it.
That long shaft is not as bad as it looks.  The real culprit is a fimsy L bracket that lets the motor bob up and down too much.
It can't run no 5 mph. But it runs smooth and steady once you get it going a little, it always starts, and it
doesn't stall.  That's way better than the stock engine.


I am going to do another one in a few months, when I can get to it.  I am going to try a 4:1 gearhead, which will
get me all the length I need, plus monster torque, which should get this engine silky smooth.  My only worry is
that since the engine isn't geared fast as it is, it may be too slow.  I will need to compute RPMs and speeds before
I do it.

But this is really getting off the thread topic!

[Cajonpassfan]

Otto,  you have a steam loco with such a large (42")  wheels in the trailing truck with inside bearings?  Which locomotive is it? I don't ever recall seeing a US prototype loco with that type of a trailing trucks.  I only see such arrangement on European steamers

P-ski,
ATSF 900/1600 class 2-10-2's;
Some solid disk, some spoked. Also early 1200 class Pacifics...
Otto