Usa Trains Diesel Locos Drive Axles

Hello

Does anyone have source for the plastic gear wheel at the centre of the drive axles on USA Trains diesel locos power bogies? I have got lots of stripped ones but the actual wheels are OK and I wonder if they could be re-used.
Bill
 
Is it the teeth of the gear that have stripped, or the splines where the metal half axles push in?

If it's the latter, there are a couple of patches that can work.

The simplest is to bind them tight with fishing line or similar and them lock that in place with glue. No disassembly required but if it doesn't work that's it.

The other is to dissemble the axle, centre gear and two half axles, add brass tube collars of the appropriate size to the centre gear and the then force the half axles back in. I've actually just sourced some of what should be the right tube, but I'm going to test it out on a half dead set before I list anything.

If it's the actual gear teeth, replacement is the only option. USA trains don't sell them separately, just complete axles. NWSL did offer aftermarket replacements for some types, machined in harder plastic to boot. They were also relatively expensive, similar in price to a whole OEM axle. NWSL's catalogue seems to be a bit hit and miss at the moment and supplies of some of the more special purpose bits can be hard to get.

NWSL also used to sell replacement wheels/halfaxles in a range of diameters, flange depths and materials, similar applies - expensive but nice and hardwearing, not everything listed is available any more.

《Plug》If at any point you want give up and just fit more USAt originals I have then for the 4 wheel blocks. Ones for the 6 axle loos are basically unobtainable, I haven't been able to get any except the PA for a couple of years now.

Jonathan
g-bits
 
Small brass tubing on the axles will do the trick:

axles-01-cracked.jpg


axles-04-press-on-rings.jpg


Read my page on this subject:

http://www.elmassian.com/index.php?option=com_content&view=article&id=150&Itemid=167

Greg
 
Hello All.
I noticed this thread with interest. About ten years ago, I purchased a USA Trains GP7/9 from a local radio control and train store. At the time, I was new to G Scale and should have known enough to have tested the locomotive at the shop. Imagine my surprise when I got it home and discovered that the wheels were wobbling. The motors and everyhing else was nice but the wobbles weren't going away.

I immediately contacted the shop where I bought the locomotive and explained the difficulty to the owner. His response was that I should contact the USA Trains Co, Charles Ro. They told me that the parts were not available and that there was no warranty.

That being the case, I decided to pull the motor covers off and take a look. There were cracks on each side of all four of the worm gears in the motor blocks. I set about to make a repair using some aluminum stock that I had in my machine shop. Using my lathe I turned 8 identical collars that were the same ID as the OD of the plastic gears. The wheels came out readily since they were loose.

I pressed the collars on each side of each gear and then pressed the wheel units back in and checked for gauge and alignment. It came out perfect and the locomotive now has several hundred hours on it with no wobbles.

Here are pictures. I could also have used brass, but had none available at the time. This is the rear truck but the front is identical.

Regards to all from California. :happy:

USA%20Trains%20GP7-9%20UP%20%2012_zpsqicjfbud.jpg


USA%20Trains%20GP7-9%20UP%20%2013_zpstgqwufyb.jpg
 
Nice solution when you have the tools to make your own. I found off the shelf tubing that just needed 10 seconds with a Dremel cutoff wheel to slice sections off for what I needed.

Greg

p.s. funny they said the parts were not available, USAT has always had spare wheelsets in stock, maybe they meant you cannot buy the plastic gear casting alone.
 
Nice solution when you have the tools to make your own. I found off the shelf tubing that just needed 10 seconds with a Dremel cutoff wheel to slice sections off for what I needed.

Greg

p.s. funny they said the parts were not available, USAT has always had spare wheelsets in stock, maybe they meant you cannot buy the plastic gear casting alone.


I see that the worm gear sets with the wheels are now available. Either I failed to see that back then or, I decided that $19.95 per axle was too much to pay since I could easily repair them. That would have been $79.80 for the for axles plus $10 shipping and that was out of the question at the time. The dealer refused to help out since I bought the locomotive on a closeout for something like $200. They are selling for $334.95 plus shipping now. That is a nice locomotive, however.

ModelRailroad003_zpsf7a0666b.jpg



The motor trucks are available also but they are $49.95 each. In general Charles Ro is easy to deal with and the small parts are quite reasonable, however the shipping is heavy at $10 for a $5.00 item. LOL.

As you say you can find off the shelf tubing that would easily fit. That would be a good repair as well. I would encourage anyone with the same problem to undertake the repair themselves as the wheels, once pressed in don't generally wobble or come out again.

GNM


http://www.charlesro.com/gp7parts.html
 
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If you call Mike at USA Trains (yes I know it's an international call), and tell him it's on a new loco, newly purchased, most of the time he sends you new wheelsets free.

Replacements are not cheap, but not super terrible. I sleeved all of my locos. A note, thick wall tubing can work, but in the smaller locos, often there are clearance issues with even a moderate wall thickness... like the centercab and the nw-2...

Greg
 
If you call Mike at USA Trains (yes I know it's an international call), and tell him it's on a new loco, newly purchased, most of the time he sends you new wheelsets free.

Replacements are not cheap, but not super terrible. I sleeved all of my locos. A note, thick wall tubing can work, but in the smaller locos, often there are clearance issues with even a moderate wall thickness... like the centercab and the nw-2...

Greg

There are indeed clearance issues on the GP7/9 also. Note in the pictures above the small clearance on either side of the sleeves. As I mentioned, ten years ago or so, I knew no one at USA Trains so I was on my own. In any case, part of the fun of model railroading is doing your own repairs.

In the past three or four years, I've added a number of the smaller LGB locomotives to my rolling stock. I picked up a Stainz, a Schoema, a Furka Oberalp and a 2076 Steamer. all 0-4-0's. All of those were bought cheap on eBay needing repairs and all of them are running nicely now.after some new gears and a motor in a couple of them. My first G locomotive was the 20232 2-4-0 steamer with two passenger cars, which i still have. It's very smooth and sort of cute and stylized.

On the way are a USA Trains F3 A and B units. Hopefully no sleeving will be needed initially since they are new but when the time comes, I'll be ready.

I've got about 160 feet of track in a 20 X24 room in the top of my barn. So many trains, so little time and money. LOL.

.
 
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The cracking problem was finally solved with the release of the GP30. USAT changed the knurling on the axle shaft. Subsequent runs of earlier locos also had the fix.
 
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