Slaving two PF-M motors

[roamingstop]

Im building up a custom train locomotive (freight) and was thinking about slaving two PF-M motors to provide power to the trucks (bogeys). I know using a PF train motor would probably be better, but they wont fit on the base (split level) which I am using.

Currently my idea was to mount the two motors into a differential, and use this to generate power on a drive shaft, which in turn is split between the two ends of the split level train base. However will this work? Or is it better to link the two motors directly (with pole reverser if necessary).

Is there any good resource online to check out? I know of some examples in Railbricks which shows some PF-M motors directly linked, but am not sure if this is the best solution.

Thanks

Edit: I should add; the reason for using PF-M is the size factor - the PF-XL is too large in the 6 wide model. Speed is not an issue; it will be pulling a long train...

Edited May 1, 2011 by roamingstudio

[grindinggears]

Naturally all Motors have varying speeds, but that makes not a big difference in your case.

A differential would be the best solution because it allows the motors to spin with every speed. But housing a differential in a train sounds nearly impossible.

So I suggest you to take the easy route: pair two M-Motors directly together so they turn the same driveshaft. This will give you more space to add some details and won't inflict the train's overall performance.

If you have more than two M-Motors you should first see which of them fit together best in terms of speed.

Use this contraption by Nico71:

Power both motors with the same battery box and see which motors have the smallest difference in speed.

hope I could help

[DLuders]

OK, you want to use either the 87058 "Train Base 6 x 34 Split-Level without Bottom Tubes" (which comes in the new 10219 Maersk Container Train set), or the similar 2972 "Train Base 6 x 34 Split-Level with Bottom Tubes" part (pictured below). Those big holes do offer a tempting route for driveshafts. It may be possible to have two Power Functions (PF) Medium Motors deliver all of their power in one or two driveshafts (all in a 6-studs-wide package).

I think that it might be better to have the two PF Medium motors pointing OPPOSITE DIRECTIONS on the lower, central platform, and using a simple 90-degree bevel-gear arrangement to drive the bogey wheels. The driveshafts would running through the big holes in the split-level platform. As you noted, an 8869 "Power Functions Control Switch" would be necessary to change the direction of rotation for one of the motors.

Edited May 1, 2011 by DLuders

[roamingstop]

If you have more than two M-Motors you should first see which of them fit together best in terms of speed.

Use this contraption by Nico71:

Thanks Grindinggears - that is exactly what I had in mind (as also correctly pointed out by dluders). Just need to find time to sit and build it...