pic: Demo Transmission 222

[Manoel]

Originally Posted by sanddrag

I'm wondering if a laser machine would be able to burn out some lexan (0r acrylic) gears without melting it. It doesn't have to be super precise, just functional enough for a demo box. If not, maybe a waterjet? Do you have access to either of those? With proper indexing equipment and a gear cutter you could even cut your own gears on a mill.

I'm not totally going for the friction wheel thing. I think gears would be way cooler, even if some extra work is involved.

A few notes about laser cutting:
One of our few sponsors owns a shop specialized in laser cutting, so most of our "professional" looking parts are made by him.
He has cut us several acrylic gears and we didn't have a problem with that (except... acrylic shatters - rookie mistakes ), though it should be noticed that those were large pitch gears - for the window motor, I think. Not sure if finer pitch gears, like 20 or 32 DP, would be cut correctly.
Another thing to notice is, allegedly, bad gases are released when polycarbonate is heated/melted, so he only cuts it when the shop is closed. Since we are thankful enough for his sponsorship, we don't ask him to cut any polycarbonate for us. That'd probably be a similar issue with other laser cutting shops: they won't do it or maybe they'll charge you a ridiculous amount for it.

[Gdeaver]

Some small timing belt super glued to the circumference of the polycarb would allow a fairly functional gear. No machining required.

[team222badbrad]

The belt idea would probably work, however you would still have to machine something down to accommodate for the thickness of the belt.

I would not use the timing belt as a gear, I would just use the belt for traction. The main I idea of this to keep the shifting part of the transmission clear, so attaching one belt to each of the other "wheels" besides the shifting "wheels" would probably give enough traction.