pic: Vex Face Bearing Gusset Gearbox

[asid61]

Originally Posted by aldaeron

I knew one of the many gearbox designers would know how to help. Added link to the STEP above.



It is the .090 sheet metal Vex Face Bearing Gusset. It is sized for 84 Tooth 20 DP gears (C-C is 2.103). Vex Drawing is here.

Basically you get two gear reduction pairs of any two hex bore 20 DP gears that add to 84 teeth. The largest reduction is 66:18 (3.67).

It may not be as reuseable as other gearboxes and does take some assembly work, but is an entry level way to get into custom gearbox design. I think you could stack two 6" pieces of VersaFrame and make a standalone gearbox if you want.

I haven't priced it (depends on your gear choices and if you go as crazy as I did with extra supporting gussets). My quick calc says as shown it is $50 plus the cost of the 5 gears (~$50), plus the mounting hardware, collars and shaft pieces. Not as cheap as the Vex Double Reduction at $60, but not bad for a custom gearbox with no CNC required IMO.

-matto-

The largest reduction could even be 70:14 if you use 3/8" hex bore gears.
If there was a way to easily align these across a tube, like some kind of C-channel acting as a square, you could just make a gearbox with oversized holes made with a step drill and a piece of versaframe.