6WD: Driving the Center Wheel

[Ty Tremblay]

When directly driving the center wheel of a 6 wheel drive train from the output shaft of a gearbox (with chains powering the outer two) where is it best to put the output shaft bearings?

Should there be one on either side of the gear (i.e. Toughbox style), one on either side of the wheel, or one on either side of the whole system? I know you're not supposed to put 3 bearings on a shaft, but would it be acceptable in this case?

[jblay]

It seems like all the cases you are bringing up would work just fine so long as you make sure not to have 3 bearings. It just comes down to how your chassis looks and where it is easiest and lightest to put the bearings.

[Ty Tremblay]

Thanks, I was just worried about cantilevered wheels.

[Alex.q]

I haven't heard this before. Why cant you put 3 bearings on a shaft?

[kaliken]

Originally Posted by Alex.q

I haven't heard this before. Why cant you put 3 bearings on a shaft?

My initial thoughts is that your 3rd bearing can institute some preload onto the shaft if it not perfectly aligned with the other two bearing. i.e. 2 points a line will always intersect both point. 3 points you may not be able to draw a line to intersect all points.

There is nothing saying you cannot put 3 bearings on a shaft. We have done it before on our robots, but we have been pretty good about alignment and manufacturing these pieces.