MakerBot Industries blogger MakerBlock is working on a clockwork spider, and went the route of designing his own gears. He’s sharing his observations of designing and printing his own clockwork parts on the MakerBot blog. Here’s a sample:
Don’t make parts too thin. The parts I printed tended to be designed too thin. If you are designing a multi-part mechanism, don’t skimp on plastic and make the parts unnecessarily thin or small. My original gears and cogs were 2mm thick. The problem was that it was easy enough for the teeth in one gear to simply miss the other thin gear. My new design uses gears that are 5mm thick and they never miss one another.