Delta ML250 miter saw

From Fozzee.net

This is my Delta ML250 miter saw, that I scored off Freecycle. It's got a 10" blade, and about 2hp (peak), though I don't know that I buy that number (not in it's current condition anyhow). The brushes are about trash, as the motor sparks quite a bit. Case in point, I cleaned it up quite a bit, refaced the fence, and it seems to work fine. At some point, I might add work clamps, and I intend on running an abrasive blade to use it as a chop saw. The blade in it was a Skil Carbide (24t, I think)... Anyhow, this was the 3rd saw I acquired this year (2008).

Update: This saw has now been rebuilt a variety of times, including most recently February, 2010. I'd recently replaced the brushes as they were just disintegrated, and the saw promptly started popping the breaker when fired up, even without load.

I disassembled the entire saw, removed the motor shaft (which has the commutator, armature and a stamped cooling fan pressed onto it, and a spiral gear cut into one end of the shaft itself) and put the entire shaft assembly up in the Lathe to resurface the commutator while I had it apart. After turning it with a regular cutting bit, I applied sandpaper. Ideally, I'd have done so using a block of wood or something, but I didn't. Not cool having a sharp fan flying a few inches from one's fingers... I also scraped any remaining copper from between the segments of the commutator with an X-acto knife.

After that, I inspected the field windings to make sure that the enamel was still good (it was) and discovered a damaged connection on the brake windings. Rather than try to repair it, I just disconnected it entirely. The brake hadn't really functioned for some time, so it wasn't a big loss.

After a dry run, I reassembled the whole mess, and it works great(ish). It'll be better once the brushes get seated.

Probably about time to buy a dedicated cutoff saw for metalwork; That or hope someone's throwing one away :)