I found an old MDC Climax in a box of my dad's old HO stuff, likely it's been untouched since the 70's-80's. I know this is not a fine locomotive mechanism, sounds a bit like a coffee grinder, but I did some repairs on it and almost have it working. Each power truck has a drive shaft with two worms on it, engaging a spur gear on each axle. This drive shaft is driven from a central gear tower via a u-joint. The portion of the u-joint on the truck side is a little cross-shaped doohickey made out of engineering plastic. The issue I'm having is this little plastic cross is spinning freely on the steel drive shaft. I suspect the loco was run without proper lubrication and so the plastic parts loosened up. Should I try ACC to glue the plastic to the steel shaft? Seems unlikely to work with the slippery engineering plastic. Should I try drilling the plastic part and through the .092" shaft with a small hole and using a bit of brass wire to pin the plastic part to the shaft? Seems like I might have trouble drilling through the steel shaft with a tiny drill bit. Any advice on how to solve this? I see suggestions of using NWSL stanton drives and while I'm sure that's wonderful, spending $160 on this locomotive is not going to happen. I do see some people repower with a bachmann spectrum 44 tonner, and I think I have one of those elsewhere in my dad's stuff, so maybe, but ideally I'd like to have a working 44 tonner _and_ a working climax, so if I can get this old coffee grinder working without replacing the mechanism, that would be my preference. Thank you!
That looks like the same problem I have with two MDC Shays (one partially completed kit and one completed kit) I bought at a train show. It seems to be a common problem with the geared locos. For now the completed one is a nice static display and I'm using the partially completed kit (frame, motor, trucks, drivetrain) as a test subject to find a solution I can apply to both. I tried ACC on the motor shaft coupling but that worked for about three seconds. The other problem I have (and what likely led to the coupling failure in the first place) is that the gear/worm transmission sticks. It can even pop the truck gear covers right off from the torque! So we're both in the same boat... For now, the complete Shay is a nice display piece in my living room.
Is ACC some variety of contact cement? Epoxy seems more promising than that. Scoring the steel shaft so the epoxy has splines to seep into will help.
what really seems to make a difference on the old metal die cast parts is to spend some time and make it smooth, remove flashing and out of round especially ... it will be noticeable in 'less noise' ... it's not super quiet but a lot better than stock parts, lol
@logging loco: here's a couple of photos of the completed Shay. One from the side and the other showing the drive shaft underneath the engine: It's a nice-looking engine, but for now, it's a static display piece. One day, I'll find the solution.
Have you looked at North West Shoreline's website? I believe they used to have some products for MDC Shays.
That's a thought - epoxy might work. Since the drive isn't working right now I was thinking of drilling a hole and pinning the u-joint to the driveshaft later tonight with a piece of brass rod. If that doesn't work out, I can try epoxy.
I found some 0.032” brass rod and drilled through the universals and drive shafts with #67 drill bit. Then I dipped the rod in thin acc and pushed it through the hole and trimmed the ends. Seems to have resolved the problem. The steel shaft was softer than I expected. This might also help your shay, although I’ve read the main thing to do is to remove the side rod teeth from all but one gear to keep them from binding up. Sent from my iPhone using Tapatalk
I see the difference now. Your Climax is using the about the same motor as my Shays. Your drivetrain is in the tender, which isn't possible with the Shay (one frame holds all). Thanks for sharing your photos. Oh well, at least I got to show off my Shay.
I'm confused. The Climax has no tender. The difference is the Shay drivetrain has longer driveshafts than the Climax drivetrain. The drivetrain is no piece of art, but I got it to run smooth enough that it can creep from tie to tie in about 6s.
The thing is pretty short. Hey, so I have read the major malfunction w/the mdc shay is it's essentially impossible to get the main drive to run while all the shaft on the side is hooked up. I've seen ones that ran well that had all but one gear on the side rod filed down. Then the side rod still turned without binding. I've also seen on some layout where they weren't hooked up at all. Does your mechanism run if the side rods are not hooked up?
That is really cool! I hadn't thought of that. But that's not going to be possible unless I either get the plastic coupling to stick to the smooth metal motor shaft, or if I turn the top drive gear manually... Hmmm... I need more coffee... brain fuel...
You can see above how I got the plastic u-joints to stick to the metal driveshaft: drill a hole through both and pin it with a bit of brass rod. Sent from my iPhone using Tapatalk
