I have one of those portable 3 wheel bandsaws. I bought it *used* at an auction last year. I tested it before I bid, and ran it when I got home, and it worked fine. I cut a few smallish boards a while back with it, and its been sitting ever since. Last week I began cutting a piece of
3/4" thick pine. Halfway thru the cut, the motor got real slow, then stopped entirely.I tore the whole saw apart, and found the motor was dead. I proceeded to tear the motor apart and found the windings are fine. The problem is that the brushes are very tight in their plastic holder. In fact, so tight I had to use a screwdriver to move them. I removed them and cleaned both the carbon brushes and the holder with rubbing alcohol to remove all dirt and any oils.
They are still very tight. So, even if the brush springs are weak, the brushes need a lot of force to even move them in their slot.
This has me puzzled. Obviously the carbon brushes can not expand. so the plastic holders must have shrunk. Since the saw was previously working, this is not because someone put in the wrong size brushes.
My question is how the heck can that plastic have expanded? I thought that maybe it got hot, but it's smooth, otherwise it would probably be rough from heat.
The plastic is part of the motor housing, not slide in pieces. Obviously poorly designed. A quality motor would have brass brush holders. The saw is a Springfield Cast 12" bandsaw - model 20412. (There is also a Duracraft 20412 .... identical saw). But it appears from all my googling, that this saw does not have anyplace to buy parts. (Both companies must be out of business).
I'm left with either filing the carbon brushes thinner, or filing the plastic slot wider (or both). But I still can not understand how these brushes once fit, and are now too tight? The motor is part of the saw itself, not an external belt driven motor, so if filing it dont work, the whole saw is junk, since parts are not available.