Lathe wiring

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elewayne
Posts: 42
Joined: Fri Aug 29, 2014 4:10 pm
Location: Houston

Lathe wiring

Post by elewayne »

Hi guys, Hope I fine everybody well at this crazy time.
I have a 1938 south bend 9" lathe. the motor, which I think was original, has burnt up and it too expensive for me to rewind it.So I got a 1 hp Daton.
slightly used. The motor guy I got it from says it can be wired both 120 or 220. I'd like to have it 220.
But can I still use the original barrel switch for forward and reverse? does anybody have wiring diagrams on how to do that?
I have a buddy who is actually an electrical engineer, was with Kellogg until he retired. He's a talented guy and has wired a number of houses, including my addition and remodel, but He's having trouble trying to figure out how to still use the forward and reverse feature. So we are looking for more information.
We have the lathe wired 120 right now but with no reverse, just forward.
I'm no electrician by any means, but Dave can read the diagrams if we can get some.
thanks
John Hasler
Posts: 1852
Joined: Tue Dec 06, 2016 4:05 pm
Location: Elmwood, Wisconsin

Re: Lathe wiring

Post by John Hasler »

The switch will work with 220. You wire it the same as with 120 but using L1 and L2 instead of line and neutral. You don't connect up the neutral at all (but connect the ground, of course).
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ALCOSTEAM
Posts: 762
Joined: Tue Feb 04, 2003 9:20 am
Location: illinois

Re: Lathe wiring

Post by ALCOSTEAM »

Of course you will have to change some wiring on the motor to account for the change in voltage. If you just hook up 220 to the same terminals you took the 120 off of you will quickly let the magic smoke out.

Is there not a diagram on the motor ?
Give me a bit and I will look up a Dayton 1 HP single phase motor.
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ALCOSTEAM
Posts: 762
Joined: Tue Feb 04, 2003 9:20 am
Location: illinois

Re: Lathe wiring

Post by ALCOSTEAM »

Depending on what Dayton model you have makes a difference in how the wiring is set up, either wires or on a terminal block inside the end of the motor. Basically in 220v you are putting the main windings in series. To reverse a single phase motor you just need to reverse the wires on EITHER the main windings or the start winding but not both.

On most single phase motors these days it seems the start winding is always red and black.

On your drum switch you will have a set of contacts that always cross over to the same set no matter which direction you turn the switch. You will also have a set of contacts that will cross over so that in one handle direction the start winding is opposite the run winding.

I will look in the shop later and see if I still have a Dayton drum switch. I think it would be much easier to show than to explain. I thought about pasting a drawing from online here but most drawings of the drum reversing switches are so over done that they are confusing.
SteveM
Posts: 7763
Joined: Mon Jun 27, 2005 6:18 pm
Location: Wisconsin

Re: Lathe wiring

Post by SteveM »

If you want confusing, here's the wiring diagram for a 2-speed, 3-phase reversible motor.

This is the Pratt & Whitney 3C mill and lathe control.
PW_Switch.jpg
Steve
Russ Hanscom
Posts: 1955
Joined: Wed Mar 15, 2006 11:10 pm
Location: Farmington, NM

Re: Lathe wiring

Post by Russ Hanscom »

If you want confusing, I have a three speed, three speed, reversing motor on the drill press.
SteveM
Posts: 7763
Joined: Mon Jun 27, 2005 6:18 pm
Location: Wisconsin

Re: Lathe wiring

Post by SteveM »

Russ Hanscom wrote: Thu Jun 18, 2020 1:46 pm If you want confusing, I have a three speed, three speed, reversing motor on the drill press.
You got me by one speed, but the P&W motor feeds into an infinitely variable gearbox :-)

Steve
Andy R
Posts: 441
Joined: Wed Sep 26, 2007 2:18 pm
Location: So. Calif.

Re: Lathe wiring

Post by Andy R »

When I re-powered my 1940 South Bend 9-inch workshop lathe I found a paper wiring diagram inside the original drum switch that was helpful.
1/4hp is more than enough for that lathe btw.
SteveM
Posts: 7763
Joined: Mon Jun 27, 2005 6:18 pm
Location: Wisconsin

Re: Lathe wiring

Post by SteveM »

Andy R wrote: Thu Jun 18, 2020 2:49 pm 1/4hp is more than enough for that lathe btw.
While South bend sold 1/4hp motors, they specifically listed 1/2 hp motors for 9" lathes.
I wouldn't even go down to 1/3 hp on my Atlas, which is nowhere near as rigid as a South Bend.

Steve
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