Dress Commutator with Shopsmith

[Culprit]

My '76 Ironhead wasn't charging. I took the generator off to find that the previous owner decided that a gasket between the generator and engine case was optional. That and the shaft oil seal was folded back on itself. And the ball bearing was missing one of it's metal shields. What was the previous owner thinking?

I also found the brushes to be stuck and had dug into the commutator some. I mounted the armature on the lathe, and used some 400 and 600 grit sandpaper to clean it up. 80% of the circumference of the commutator cleaned up pretty quickly and highlighted the damaged section. It won't take a whole lot more sanding tomorrow to finish it up. I'll probably finish up with 1000 grit.

Score another victory for the Shopsmith! Without the lathe capability I would probably be spending several hundred on a new generator.

PS: the spacers between the coils are wood. That's cool.

[STB]

Outstanding three thumbs up.

[JPG]

A fine file will get it down to the low points.

[pieceseeker]

Yea, I've cleaned up many commutators by chucking it up in a drill and putting the drill in a vise, but then, I didn't have a SS at that time.
A good file will start the process nicely like mentioned above.

What brand live center is that? Nova?

[billmayo]

I have used a hacksaw blade (teeth ground off on the sides) to cut the formica between each rotor copper segment to a least 1/32" below the copper segment tops. Otherwise the formica will prevent the brushes from riding on the copper segments after a few days of operation.

[Culprit]

I don't know what brand the live center is, but I bought it from PSI, Penn State Industries.

I didn't have a fine enough file, so I stuck with sandpaper - the inch wide strips on a roll that I use making pens. I used 400, 600, 1000, and 2000. It came out looking like new.

I checked the mica between the segments and the grooves all looked deep enough to me. I cleaned them out to make sure no gunk or sanding dust was filling them in. Now that Bill mentioned the 1/32" number, I'll check it before reassembly.

I put the generator back together (minus the bad oil seal) with the old bearings to bench test it since I don't have a growler. I hooked it up to the battery and it ran quite nicely. Armature to positive, field and gen case both to negative. I know this test doesn't mean 100% that the generator will work on the bike, but if it hadn't passed this test, then I would have known 100% that it wouldn't work!

Now I'll go order the bearings, shaft oil seal, and the gasket that the previous owner felt was optional.

[billmayo]

I checked the mica between the segments and the grooves all looked deep enough to me. I cleaned them out to make sure no gunk or sanding dust was filling them in. Now that Bill mentioned the 1/32" number, I'll check it before reassembly.

As long as the brushes do not rub on the mica, you should be be OK. I guessed at a depth as I did not remembered the actual depth from years ago.

[JPG]

As long as the brushes do not rub on the mica, you should be be OK. I guessed at a depth as I did not remembered the actual depth from years ago.

Anything > 0 should be ok. Need to allow for some future wear though.

Getting TOO aggressive will lead to loose segments(not good!).

[skou]

A long time ago, I hung a Dodge 360 crank in my 10ER, to polish the main bearing journals. Didn't turn them, just used the ER for a crank holder. Engine ran fine, when I was done. Made it from Oklahoma to California and back, with no issues.

You'd be surprised just what a Shopsmith can do!

steve

[JPG]

A long time ago, I hung a Dodge 360 crank in my 10ER, to polish the main bearing journals. Didn't turn them, just used the ER for a crank holder. Engine ran fine, when I was done. Made it from Oklahoma to California and back, with no issues.

You'd be surprised just what a Shopsmith can do!

steve

Sounds like a knuckle buster to me!:D