I have a Tenshodo 4-8-4 Locomotive and the motor seems to run well. The problem is or was the rubber joint that went from the motor to the drive wheel. Does anyone know of a replacement part available or a way to replace it? Otherwise I believe it will run well. Any help or directing me to some parts would be GREAT. Thanks in advance. JEff
A "quick and dirty" fix would be to get some neoprene tubing used for fuel line in model airplanes. Just make sure the inside diameter is a fairly tight fit on the motor and gear box shafts. A better alternative would be to use Northwest Shortline U Joints. http://www.nwsl.com/hardware-parts/universal-coupling-sets Hope this helps. Andre
Andre's suggestion of the NWSL U-joints is a good one--they're made with variable size connections for the various size of motor/gearbox shafts. However, I've found that in some cases, those Tenshodo gearboxes have a lot of back and forth play to them, and when power is applied, they move forward enough to disengage the U-joint. I had that problem with a Tenshodo 2-10-2 when I replaced the tubing with the NWSL U-joints, and even adjusting them didn't relieve the problem with this particular locomotive. So it depends on how much 'play' you have in the gearbox. Neoprene will work, but in some cases, it's almost TOO flexible. I find that it works best on can motor to gearbox installations, not necessarily with open-frame to gearbox, where you have so much 'play' between motor and gearbox. I'd actually look for a 'stiffer' airplane tubing, with more plastic 'girth' around the tubing hole. But get the stiffer tubing that has to be 'forced' on both the motor and gearbox shaft. It might take some adjusting back and forth to get the motor running smoothly in both directions for equal play between them. That's what I finally had to do with my Tenshodo 2-10-2, but the result has been an exceptionally smooth-running loco. Hope this helps. Tom
Andre's suggestion of the NWSL U-joints is a good one--they're made with variable size connections for the various size of motor/gearbox shafts. However, I've found that in some cases, those Tenshodo gearboxes have a lot of back and forth play to them, and when power is applied, they move forward enough to disengage the U-joint. I had that problem with a Tenshodo 2-10-2 when I replaced the tubing with the NWSL U-joints, and even adjusting them didn't relieve the problem with this particular locomotive. So it depends on how much 'play' you have in the gearbox. Did you use a torque arm, Tom? That might have alleviated the problem. For the OP, here's a link to a Mark Schutzer loco rebuild clinic PDF where torque arms are discussed and the technique illustrated. The torque arm discussion is on page 26 of 42. http://markschutzer.com/Brass_Clinics/RebuildingBrass2008a.pdf Andre
