If I weld 2 gears on each end of the axle, would this be enough of a reference which would let the wheels turn instead of spinning uselessly?

IF you have a tail/weapon of some sort attached to the axle....Yes.

Stinger is mainly produced from stainless steel. It has 2 identical wheels with all the workings mounted inside. The wheels drive round a fixed axle which has the tail weapon attached through a friction clutch. Structure and protection are provided by 3mm thick spun steel domes and and the Kinetic Energy of this rotating mass is transferred into the tail to make a substantial weapon

Stingers weapon is its tail. This weighs 6Kg and is made from steel which has been sharpened and tipped with Stellite. The tail has no actuator, but is driven by inertia from the wheels. When the motors are stopped, the wheels continue to roll so the transmission turns the axle which transfers their momentum into the tail. When the motors are reversed from full speed, the tail slams overhead with the force of a 14lb bowling ball being dropped from 60 feet!

(Message edited by woody on May 02, 2007)