My Bachman H.O. 44 tonner is frustrating! It would fit perfectly as an industrial switcher on my layout but no matter what I try, it does not do well on curves (my minimum is 24" radius). I have actually purchased two such diesels (duh!) and find both do the same thing–lurch on curves. It is not the track (clean, smooth, no problem for my other motive power) nor the power supply (filtered D.C. with adequate feeders–no problem to the other engines). I believe it is in the design–the worm gears from the motor shaft are afixed to the frame and the spur gears pivot with the trucks. The engine is O.K. on tangent track but lurches on virtually every curve, either in trackage or turnouts (#5’s). Is there any solution? I am spoiled to the Kato NW-2 and the Steward VO-1000 for switching performance but I had hoped this 44-tonner would be acceptable (it is on straight track!). Is this simply a design flaw or am I missing something?
The wheels are in gauge and the phenomenon occurs on all my curved trackage. I sent one of the units back to Bachman and they sent it back as “fixed.” No change. Thanks for the thought, however.
Are these the new “single” motor design or the old “dual” motor design? I would assume, since you mentioned that you purchased two of them, that they are newer design? The old dual motors had problems. Mine would “grind” and pulsate going around curves when the switcher was faced in a particular direction. Had to ask…
Another thing to check is to pull the shell off and see if it still does it. The coupler housings can also cause binds with the trucks. Good luck with that! I have 2 and done have the issues on curves.
Don’t have one of them but what you are describing is a classic bind of some type that only interferes when one or both of the trucks are turned. I doubt it is in the truck itself but in one or more of of the universal joints. You should be able to cause it to happen by removing the shell and run the engine while holding it with one hand. Then turn one or both of the trucks (using your other two hands :-)! ) and the binding should show up. Then you can troubleshoot from there.
Thanks for all the suggestions. I had two of the old “two motor” 44 tonners before. This one has the single motor with universal joints to the worm gear towers. I still tend to think that the bind is due to the immovable position of the worm gears in the frame (held by screws to the frame). When the trucks pivot, the geometry between the spur gears and the worm has to change. But one of the replies said yours did not have such a problem. I have disassembled the unit, checked for binds, wobble, and burrs in the gears. I even "swapped out"components with the second unit, now used for parts, all to no avail. Am I off base about my “worm gear binding” theory?
The last word on my 44-tonner problem. After backing the mounting screws for the worm gear assemblies off one-half turn, the performance improved from “intolerable” to “resonably good.” I have run the engine on a regular “switching job” of about 1.5 hours and experienced just minor hesitation. I might add thin gaskets between the gear assembly and the frame to see if this cures the problem. By the way, after doing this, the loco was much quieter. Thanks for all the suggestions.
Trauma?
Try putting decoders in the lil devils![}:)]
I did both of mine, and the wife will tell you.
The cats learned a few new words that day![:0]
I just kept telling myself:
Model Railroading is fun, Model Railroading is fun, Model Railroading is fun, Model Railroading is fun, Model Railroading is fun, Model Railroading is fun, Model Railroading is fun, Model Railroading is fun, Model Railroading is fun, Model Railroading is fun, Model Railroading is fun, Model Railroading is fun,
etc, etc. etc…