For an 11" lathe you should be looking at something in the 3/4 hp range
to give you the power you will wantto make heavier cuts. 220 volt motors
are preferred over 110 volt since the current is half on the 220. BUT,
for 3/4 HP, the current isn't excessive on the 110 volt. 3 phase motors
are cheaper, smaller, and smoother.

Your need for a 1140 prm motor is a real pain, used/surplus/cheap is not
going to be in your future.

I think I'd look for a 3/4hp cap start cap run 240 volt 1750 motor. Use
a slightly SMALLER drive pulley on the motor and you should be able to
pick up a few hundred rpm over the stock unit.

Peter Grey wrote:
Hello all,

I have a '33 11" SB lathe with a '31 Westinghouse 1/2 HP motor on it. The
motor started acting up so I took it to my local motor shop who got it
running decently, but told me that it would cost a mint to do what needs to
be done to make it right (70 years of oil soaking into the winding
insulation and all that). While the motor works, it doesn't work as well as
it should, and rather than spend more money than it's worth, I'd like to
replace it. The question is; with what?

I've been told that 1931 HP were bigger than 2006 HP and that I should go
with a 3/4 or 1 HP motor to get similar work capacity. That's fine, and my
shop is wired for 110, 220 and I have both a rotary and static phase
converter. My lathe has a screw-on chuck so I don't have a need for instant
reversing (although the lathe is currently wired for reversing and I'd like
to keep that capability). My question is, are there any advantages to 220
or 220 3-phase over 110 when choosing a motor without concern for instant
reversing. IOW, do I get more real power with any of them, less power
consumption, or smoother operation? Are there advantages or disadvantages
that I haven't mentioned? Any types of motors I should stay away from? Any
types of motor that would be good for my application?

I've done a RCM Google search and haven't been able to get these questions
answered, but if anyone had a pointer to an appropriate web site, I'd be
happy to follow it. Keep in mind that I'm an electrical dunce (I had an
electrician install the RPC for my mill) so any conversation about
degaussing the flux capacitance in the field coil windings is likely to
leave me befuddled.

As usual, thanks for the advice and Happy New Year!

Regards,

Peter