Wednesday, June 13, 2007

Unisaw - Part 3 Continued

Took some additional images from the last stage, these include the broken tooth (near the bottom, 6th):

These images show the ground out front trunnion bracket (the welds have been ground down) - there's a small hairline gap in the inside corner - I'm having it touched up this weekend as well as some slight voids.

The inside of the case isn't bad - not much rust at all, mostly at the bottom (expected). No weird cut-outs or anything - just some clean-up. I've already banged out some edge dents that will be followed up with a light coat of body putty.

The base has ruts but mostly surface with little pitting - I think it will clean up well with the sandblasting - any rough spots I'll hit with body putty. There are two holes that were cut with the castors - I'm not yet sure what to do about those. Welding to the cast iron seems excessive.

Once I have the trunnion assembly pulled apart I'm starting on the motor rebuild - I may go ahead and take it apart so the commutator can be turned.

-- John


Jeremy Z said...

Unisaws don't have commutators. Commutators are only on universal (brushed) motors. Unisaws have induction motors, which work solely on magnetism.

Maybe you meant "have the rotor turned?"

John said...

I'm no expert, but from what I understand the RI (repulsion-start induction-run) motor is an entirely different animal than a capacitor-start motor. It has a wound rotor, a commutator, brushes, usually a brush-lifting mechanism, and a shorting mechanism. A capacitor-start motor
basically only has stator windings, a capacitor (or two or three) and a
centrifugal switch which sounds like what you're thinking about?

I've looked at some photos of the commutator being turned down and was thinking if I was going to take the motor apart, I may as well do it if needed.

-- John