pic: Sheet Metal Drive Module Idea

[Madison]

Originally Posted by MICHAELABICK

There are two reasons for repackaging a gearbox. The first reason is for form factor. Repackaging a gearbox means that you can make your frame adapt to it in any way you want. The second reason is weight. The repackaged gearbox has walls that are thin(comparably to the original housing). The Supershifter walls are .25" thick, the repackaged ones are at most .125" thick. Assuming that the sidewall sizes are the same, you basically just removed the weight of one AM shifter sidewall.

Andymark Shifter Sidewall = 5" * 5" * .25" * .0975 lbs/in^3(density of 6061 al) = .61 lbs

So you saved .61 of a pound if not more.

All of this is true, though the sheet metal shown is .060" rather than .120"

The real reason I did this, though, was because on a stock SuperShifter, the output shaft is 1.5" from the closest edge and, with 4" wheels, that leaves very little clearance between the Super Shifter (and its servo) and the ground. By repackaging it, I was able to increase the ground clearance -- though it seems to require pneumatic shifting rather than servo shifting.