by strangebrew » Wed Oct 15, 2014 11:27 am
If you want a "simple" gearbox..........When we were kids in the early sixties we built 'em for inline cars.
I have no pictures, nor am I going to build one for my 11' track, but see if you can follow.
Thread the motor shaft & the pinion gear as well.
Spin the pinion grear onto the motor shaft & cap the motor shaft end with a dab of solder or something.
Now the pinion will travel the length of the motor shaft on the threads.
Simply install the motor in the chassis & note the end of the pinion travel in each direction.
Use 2 different size crown gears (one on each side of the pinion...right & left if you will) that correspond with the pinion travel.
Run the car with your controller in one hand & the other on the polarty switch at the driver station.
To change gears simply flip the polarity while under power & the pinion will run out to the end of it's travel in the opposite direction & engage the opposite side crown gear. SInce the crown gears oppose each other & the motor is running the opposite direction, the car continues in it's present direction with a gear change.
You could add a polarity switch to your controller to make it handier to "shift gears". Kinda' like power shifting the 1 x 1's on the strip.
One of the guys built a small transmission using 2 different sized pinion gears on 2 threaded shafts inside a brass case filled with 3 in 1 oil
& attached it to the rear of the motor.
It's most likely "fun" to build, but the only possible use I could see would be on a drag strip.
If you want suspension....I've built some using universal speedometer cable for the rear axle (I have a thread on here somewhere)
but it's more trouble than it's worth. Just get softer tires for more wheel travel.
JUST MY 2 CENTS