pic: WIP 3 CIM 2 Speed All Belt Cim Above Tube Gearbox

[KohKohPuffs]

Originally Posted by Colin Small

Just curious, what'd you guys do to get it to work smoothly (for the most part) win one pneumatic?

Oh wow, interesting design!

Apparently three days ago I went on and designed a similar gearbox: inverted, two-piston shifting using a dog, except that the thing runs on gears entirely. Here's a picture:


Regarding how to reduce the number of pistons to one, I'm not so entirely sure, but to reduce the bending force to the shifting plate, the piston cannot be offset from the shaft. However, by doing so, you have to consider that the wheel is also going on the output shaft, and if the piston sticks out too much, it will hit. Also, the other issue that would come up would be connecting the piston to the shifting rod. Tried that once, and I hated it. You could add a third plate for spacing like what 254 did with their gearbox this year. Then piston-wheel collisions wouldn't happen anymore.

Just some things that I thought of, having designed 3+ of these inverted gearbox. Hope this helps!

[Colin Small]

Originally Posted by KohKohPuffs

Also, the other issue that would come up would be connecting the piston to the shifting rod. Tried that once, and I hated it. You could add a third plate for spacing like what 254 did with their gearbox this year. Then piston-wheel collisions wouldn't happen anymore.

Just some things that I thought of, having designed 3+ of these inverted gearbox. Hope this helps!

Not quite sure what you mean by a third plate or piston-wheel collisions. The cylinders are contained inside the gearbox so they won't be hitting any wheels.

Anyways, I like your design! I want to try doing the ribbing between mounting/clearance holes but it's never worked out well for me.