SB Model A wiring quandary.

Yes. Power are black and white. In this next photo the screw at the top is where I ran the white are and the one at the bottom of the photo is where I ran the black. It's taken apart right now because I'm replacing the bearings. The other wires are part of the motor itself.IMG20230924175631.jpg
 
so one of those green are not ground and should have had a black sleeve on it.PXL_20230924_220109472.jpgPXL_20230924_220151525.jpgPXL_20230924_220240913.jpgPXL_20230924_220253631.jpg
 
OK. Motor reversing class 101. You need 4 wires from motor to switch (plus ground makes 5) for 120 volts configuration.
I believe you have a "3-phase" type reversing switch- it will work fine if connected properly.
Most motors have an instruction like "swap wires red and black to reverse" or similar. We need that.
If there is no data plate for the motor we might need to test it with a meter. What motor info do you have?
-Mark
 
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This is the only info I have on the motor. It's an ancient thing. The lathe was sitting for at least 40 years, indoors and only had dust on it. I suspect it was set up for 220 originally but it got switched over to 110 in the 70s. I don't have access to 220 where I live in an apartment and the lathe is in the garage I have beneath my place. The serial number is 5KC43MG686E. I wasn't able to find much info on it that made any sense to me.


IMG20230920192530_01.jpg
 
I may have to break down and get a different motor with some actual paperwork I suspect. I probably won't be using reverse all that much insomuch as the chuck is on a threaded spindle and I don't want it to unscrew itself. I'm not doing any kind of heavy torque machining so it's not that much of a concern but I'd really like to try cutting threads the way I saw a YouTuber named Joe Pi do them which is in reverse with the cutter upside down.
 
many times the old motors would have a diagram on the back of that spec plate. see if yours does. a few of mine did.
 
woodchucker said:
many times the old motors would have a diagram on the back of that spec plate. see if yours does. a few of mine did.
Click to expand...
Good call. There are two plates on the back of that motor. I'd remove the plate by the wiring, opposite side of motor from that ID plate.
 
Is this a capacitor start motor? Does it have the familiar bulge cover on the side?
It's a 1/2 HP so it will run fine on a standard 120 volt circuit. Power connects to the two threaded studs.
I believe those two red wires are the start wires, swapping those should reverse it. We should test that
before connecting the drum switch.
Reverse is useful for cutting metric threads- unscrewing the chuck is not a concern during that process
 
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It's is a capacitor start motor. Correct. Once I get it up and running tomorrow night I'll connect it, then swap the black and white from what I had in the first photo and see what happens. Is that correct? The black and red wires that were on the motor when it was built are buried inside somewhere. Do you want me to see if they can be switched?
 
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