I have one of the old Bachmann 70 ton chassis with the 2 motors, what do you have to do to get the trucks to run seperately? There are wires to the circuit board, so I guess you have to move them, but what exactly do you have to do?
Assuming you want to build a four wheeled powered something from just one truck? You have to wire one motor brush to one rail and the other motor brush to the opposite rail. Wheels on one side of the locomotive are connected to the frame and the metal frame carries the electricity to one brush. You will have to arrange a wire from the other motor brush to the wheels on the other side. You may need to make wheel wipers out of phosphor bronze to rub on the treads of the wheels. Brass isn’t springy enough to make a good wiper.
For extra class, check that your power truck runs in the same direction as your other locomotives. If it runs backward you need to swap the leads to the brushes. Or take the motor apart and reverse the magnets. That’s harder, I’d stick with swapping wires.
I, too, have an older 70 Tonner. Some years ago I remember reading an article (in RMC, I think) about how you could re-wire the 44 & 70 Tonners for better slow speed performance and better overall performance. Anyone know how to do this. I’d be interested in giving it a try.
Thanks, Jimmy M
I did several of the re-wire jobs on Bachmann’s 44 and 70 tonners. It’s been a while, but I believe memory serves me correctly in that you have to cut all of the track pick-up wires and rewire each opposing truck pick-up together, sort of like an X, then run one wire to each motor pole from each of your two pick-up wires.
Ironically, I just finished running on of those 70 tonners before coming upstairs to check the forum. Wiring the motors to run together does indeed improve performance, but not nearly as well as wiring in a DCC decoder!