=20 > The problem is that anything to do with motors requires a reasonable > amount of mechanics to do something useful, which is probably beyond > time and available effort in a classroom. >=20 > Then I suspect you would get some interest in using motors. Yes, you're right. I was having a think about this today What I need to do is make up a small Meccano-type box of fittings. A couple of lead screws, a few nuts and bolts, bit of drilled panel, that sort of thing. Enough to make a crane or something with wheels I've had someone down in Christchurch wants a couple for a line- following bot for a uni project. I'm happy enough to oblige Joe --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .