Advice please: Bachman American Type drive shaft.

Chops Jan 23, 2020

  1. Chops

    Chops TrainBoard Member

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    The delicate drive shaft tip, a spline consisting of two fragile nubs, keeps wearing off by a fraction,
    and so begins to slip in the drive hub. The rapid wear appears accelerated by the locomotive going around
    the 18 inch radii of a micro layout. I’ve greased the ends without making any difference. I’ve replaced
    the shafts multiple times, but they consistently fail. The longest one has lasted is 30 hours of continuous
    Running, at exhibit, the last two replacements lasted 10 seconds and ten minutes, respectively, before
    The spline sheared.

    Is there a way to replace the junky little drive shaft with a metal one? Or better yet replace the entire shaft
    From tender to locomotive with flexible RC fuel tubing, or replace the whole motor and shaft?

    I have an upcoming museum exhibit, and no working 1860’s type American in service. Typical
    Bachman: pretty face rotten guts. I sorely wish they would upgrade the mechanicals to match
    the fine injection molding.

    Will post photos later.
     
  2. RailMix

    RailMix TrainBoard Member

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    Got anything in your Mantua/Tyco collection that could stand in for now? Ten Wheeler? Mogul? General? Not quite correct, but comparatively bulletproof. As far as the drive shaft is concerned, could you replace the nubs with a metal pin, or perhaps find someone to 3D print something out of a stronger plastic material?
     
  3. Chops

    Chops TrainBoard Member

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    Very useful ideas, thanks. I tried another Bachmann Old Timer, and the shaft failed in 10 seconds!! I got replacement shafts from Bachmann, and they lasted ten minutes! I had a NOS Mantua 10 wheeler, but it would not negotiate the curves, even with the blind center driver! I was stunned.

    I have ordered a NOS Mantua, made by Model Power, and will have that in by Tuesday. Model Railroad HQ, of Denver, swears the drive is much more reliable.

    I am eyeballing the hubs on the Bachmann piece, and maybe if I can get the drive hubs off, a length of soft RC fuel line could replace the inferior drive shaft.

    For the Grand Opening of the "Tracks Across the Desert" exhibit of the El Paso History Museum, a good friend brought in his Bachmann DCC and Sound
    Old Timer, and unlike the older Bachmann pieces, this thing ran flawlessly for hours, with sound, to boot. A good time was had by all, the module was a hit.
     
  4. RailMix

    RailMix TrainBoard Member

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    Hopefully, you will be able to replace the inferior driveshaft with something that works better. I'm also surprised that you ten wheeler wouldn't negotiate your curves. Sounds like your curves are either tighter than 18" radius somewhere or something is hanging up in the locomotive as the ten wheeler came in many train sets with 18" radius track. Good to hear, however, that you were able to solve the problem and exhibit your layout.

    BTW, how is your Gorilla Glue "water" holding up? I'm curious as to the effects of time on it as that's a technique I'm planning on trying in the future.
     
  5. Chops

    Chops TrainBoard Member

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    [​IMG] Well, I just got off the phone with a 3D print company, $100 minimum order. Cost immediately eliminates that option. I'm going to try to
    tease off the hubs and stick a piece of rubber RC fuel line on the axle ends. The hard part is not breaking the stupid thing and ending up
    with another parts locomotive.

    The Clear Gorilla Glue is about 6 months old now, and is holding up fabulously. The module is now at its third exhibit, this one at the local
    museum, and the locomotive will need to log 800 hours of trouble free run time between now and June. Since the Bachmann junk (I hope
    my annoyance doesn't shine through) eats drive axles, I forked out a $132 from Model Railroad HQ in Denver for a heavy, sturdy Mantua,
    which I believe is a Model Power repop. It too has a drive shaft, but so far, so good. Initial run tests shows it to be a rather solidly built
    piece, runs fairly, not perfectly, but fairly smoothly at about 4 volts. If it can run for the next 800 hours that way I'll be more than satisfied.

    As much as I curse Bachmann for having beautifully done plastic shells, and absolutely unreliable drive and motor mechs, and seen some
    three issues with a factory DCC unit, the newest Bachmann American Type with onboard sound and a boiler mounted motor, owned by a
    friend, operates like a Swiss Watch in all speed ranges and the sound is charming. We have only seen that piece run a few hours, so no
    telling how it works in the long haul. If it did function reliably long term, I would buy one, and keep the receipt handy.


     
    Last edited: Feb 3, 2020
  6. RailMix

    RailMix TrainBoard Member

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    Good to hear that you were able to solve your motive power problems. I suspect your new Mantua/Model Power locomotive will run smoother after it's had a chance to break in some. Where that Bachmann loco is concerned, maybe you could drill and press a couple of pins into a piece of brass rod. I think I might try that first (if I understand how the drive shaft works).
    Also good to hear that the Gorilla Glue is holding up well. Looks a lot simpler than mixing resin, etc.
     

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