[How do I?] Wiring Craftsman lathe for forward and reverse

Hi Kit,

I assume that this motor does not have a centrifugal switch and that it has a single capacitor.
single-phase-capacitor-wiring.jpg
Like this diagram. Assuming that the motor is symmetrical, simply moving the live wire from the left side of the capacitor to the right side will cause the motor to run the other way. Since your motor is dual voltage it maybe that one winding is a different value to the other. In which case it might be why the wires have been cut, ie to prevent damage to the motor.

If you know how to use a multimeter on the low ohms range you could discover if the windings are the same.
 
Do you have an ohmmeter Kit? It looks as though the start wires are connected internally- you may have to disassemble the motor to locate them. Motors that don't mention how to reverse them on the nameplate are usually more difficult to rewire. First, pull off the capacitor cover and note the colors of the wires connected to the cap- that might give some clues
mark
ps Baron: most motors of this type here in the states do have centrifugal switches, and the start and run circuits are in parallel (120 volt)
 
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Hello Mark,

It gets quite confusing, the rating plate clearly states "Capacitor Motor" but apart from the dual voltage, there is nothing to indicate what wire is what.
At least over here wiring information is either on a label stuck to the motor or stuck under the terminal box lid.

single-phase-capacitor-wiring.jpg
This is how I would expect the wiring to be with a centrifugal switch.
The switch will remain closed until the motor reaches 70% of full speed.
It is likely then, that the main winding is center tapped to give the 120/230 volt settings.
If this is the case then, as I said earlier, just move the live wire to the other end of the capacitor.
 
Baron: usually there are two run windings which can be configured either series or parallel for 240 or 120 volt, respectively, plus the start leg (capacitor, switch and winding). For the 240 volt case, usually the start leg is placed in parallel with one of the two run windings.
You're correct though, I see no information given even to wire for the two different voltages- maybe there was a booklet or a label which is missing.
I suspect this motor may be tough to reverse, and I mentioned that earlier. Digging out the necessary wires might be a difficult job.
Kit: Isn't this motor a bit small for that lathe? Seems like 3/4 to 1 HP would be a better fit. I have the bench model of that lathe and I'm planning on using a 3/4 HP motor on it eventually
mark
 
Do you have an ohmmeter Kit? It looks as though the start wires are connected internally- you may have to disassemble the motor to locate them. Motors that don't mention how to reverse them on the nameplate are usually more difficult to rewire. First, pull off the capacitor cover and note the colors of the wires connected to the cap- that might give some clues
mark
ps Baron: most motors of this type here in the states do have centrifugal switches, and the start and run circuits are in parallel (120 volt)
I do have an ohm meter. The wire colors at the capacitor are black and blue.
 
Baron: usually there are two run windings which can be configured either series or parallel for 240 or 120 volt, respectively, plus the start leg (capacitor, switch and winding). For the 240 volt case, usually the start leg is placed in parallel with one of the two run windings.
You're correct though, I see no information given even to wire for the two different voltages- maybe there was a booklet or a label which is missing.
I suspect this motor may be tough to reverse, and I mentioned that earlier. Digging out the necessary wires might be a difficult job.
Kit: Isn't this motor a bit small for that lathe? Seems like 3/4 to 1 HP would be a better fit. I have the bench model of that lathe and I'm planning on using a 3/4 HP motor on it eventually
mark
This is the motor the lathe came with when I bought it. It might be a little small though. I was just on the Grainger site and they have some wiring diagrams for their switches. I’m hoping there is a clue there. Again, thanks for your help.
 
Kit it looks like you would have to remove the end bell of the motor to get access to the back of the terminal board and the internal wires for the start winding- how badly do you want the reverse feature LOL? It's certainly possible but for this particular motor Craftsman didn't make it easy
M
 
This link is not the manual for your exact motor but it may be close enough, similar vintage and same manufacturer. The colors of the wires seem to match what you have. I'm still trying to wrap my head around what is going on under the covers. Unfortunately the instructions don't help much with that. There are instructions for reversing with a Sears switch but nothing generic.

http://www.vintagemachinery.org/pubs/222/4780.pdf

Edit:
I suspect the two blue wires go to the start winding. The diagram below shows the terminals that get connected in each position for a Furnas brand switch which is what I suspect the "9M 2982" that Sears sold was.

FurnasSwitch.PNG
 
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This link is not the manual for your exact motor but it may be close enough, similar vintage and same manufacturer. The colors of the wires seem to match what you have. I'm still trying to wrap my head around what is going on under the covers. Unfortunately the instructions don't help much with that. There are instructions for reversing with a Sears switch but nothing generic.

http://www.vintagemachinery.org/pubs/222/4780.pdf

Edit:
I suspect the two blue wires go to the start winding. The diagram below shows the terminals that get connected in each position for a Furnas brand switch which is what I suspect the "9M 2982" that Sears sold was.

View attachment 274999
This is useful, but my switch works differently. I played with it some, blew a circuit breaker in the garage, and put it back the way it was. I think I am going to run it in one direction for a while, and look for a comparable switch. The ones that Grainger sells look more like the 9M 2982, so I may go in that direction. Thanks everyone for your help.
 
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