[Mike Wittman]

Hi Andy, everyone so far is right. Avoid Acrylic. It is far to brittle to use for a gearbox. In addition, laser cutting will introduce its own stress into the material making it more prone to crack or break. What you gain in structuring your cuts you loose in how the laser affects the material.

I like what squirrel suggested. Make a template and use it to machine your Polycarbonate (PC). I often laser engrave Polycarbonate and then machine to the line. It is also nice for picking or marking center points to drill.

You can cut PC with a laser. You usually need a high wattage laser to do it however, it can be done with multiple passes. It is a very messy process making lots of smoke, leaving lots of residue and also charring the edges of your material, but it can be done.

There is an alternative material you may want to use. It is called PETG. It's properties are somewhere between brittle Acrylic and durable Polycarbonate. The advantage of this material is that it will laser cut cleanly. It can still crack and break, but it is deffinately going to hold up better than Acrylic.