ARC-170's Craftsman 101.07403 lathe restoration thread

I can't really tell where it is coming from but I'm 99% sure that it shouldn't be there. With a 2-dimensional display I can't differentiate between the actual spark and the reflected light.
 
The reflected/ambient light is constant, so the spark is pretty obvious. There are no reflections off anything, either.

There is an electric motor repair place in town that I can take this to just to be safe.

Think I should post this elsewhere and see if any electrical experts will chime in?
 
Looks like dirty contacts in the centrifugal switch, as mentioned in the comment section of this video of a motor doing the same as yours.

 
What's going on with the contact on this switch, the one circled in red. Something doesn't look right about it.

contact.JPG
 
I'm not sure what that mesh thing you are referring to is for. It's always been there. I thought it was just part of the switch mechanism.
I'll take apart the end again and take some more photos and clean everything.
 
Maybe it's there to deflect the sparks.. [edit to add: ..should the contact get dirty and or for some other reason start arcing]
 
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The only spark should be generated several milliseconds after the motor run switch is closed, when the Start switch opens after the armature is up to maybe half or three-quarter speed.
 
I took the motor to a motor place. He told me to use NO lube; just clean everything. The spark at startup is normal for this particular motor. He told me to make sure it was up high so it didn't ignite any gas fumes.

So I got some contact cleaner and cleaned everything. I lightly sanded all the contacts. I cleaned the centrifugal mechanism really well and got all the gunk off. I also wiped the oil off.

I started it up and it sparked, but ran fine. I subsequently switched it on and off a few times and got a very small spark.

I can get a used motor on CL for about $50-60. I might look at one and see if I can get it to run and see if it also sparks before I buy it. However, after talking to the motor man, it seems this is normal for this motor and that it's nothing to worry about.

I have a drill press with a similar motor (probably much newer) that I can look and see if I get a spark at startup.
 
Well, all's well that ends well!
 
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