I have an old shepard lathe and just wondering what size of motor it would take to run the thing. It has a 12 inch chuck and 48 inch it has brass bushing in the drive. Is 3/4 enought to run this beast or do i need to go biger. I was thinking about putting Woods E-Trac Ac inverter for the speed and to run a 3 phase motor on single phase. Or i have a 1 Hp 90 DC motor with control just trying to figure out which motor would be better in this place. This is stuff i dug out of the trash at work and dont want to spend a lot of money.
What would be a good speed to run the chuck 500 RPM on top end
Thanks Donald
What size of motor to run a lathe
-
Steve_in_Mich
- Posts: 1119
- Joined: Sat Jan 04, 2003 4:14 pm
- Location: Mid Michigan
Re: What size of motor to run a lathe
Your chuck is 12", what is the swing? I assume that if your are using a 12" chuck the lathe has "some" larger capacity.
3/4 Hp is probably on the light side for a 12" swing lathe. The fact that you already have the parts for either setup (DC motor and control or the Woods inverter 3 ph motor) on hand, you could try either or both and decide which you like best. If the DC motor you have is a permanent magnet type I think you will find the inverter to be the better choice. If it is shunt wound, then in my opinion it is a toss-up - so I would choose the easier installation (mounting, wiring, etc.) and start making chips. If you need more HP it will show up soon enough, meanwhile FREE is a good starting point.
Top speed? Hopfully you can find Shepard literature to guide you on this. My gut feel is that 500 rpm is okay. I hope you have enough of the original drive components to give you the low end speed/torque using a standard 1725 rpm motor to give you 500 rpm on the spindle. Porus bronze in a oil bath maybe 800 or 900 rpm. Perhaps an expert (I'm not) will have a different opinion.
3/4 Hp is probably on the light side for a 12" swing lathe. The fact that you already have the parts for either setup (DC motor and control or the Woods inverter 3 ph motor) on hand, you could try either or both and decide which you like best. If the DC motor you have is a permanent magnet type I think you will find the inverter to be the better choice. If it is shunt wound, then in my opinion it is a toss-up - so I would choose the easier installation (mounting, wiring, etc.) and start making chips. If you need more HP it will show up soon enough, meanwhile FREE is a good starting point.
Top speed? Hopfully you can find Shepard literature to guide you on this. My gut feel is that 500 rpm is okay. I hope you have enough of the original drive components to give you the low end speed/torque using a standard 1725 rpm motor to give you 500 rpm on the spindle. Porus bronze in a oil bath maybe 800 or 900 rpm. Perhaps an expert (I'm not) will have a different opinion.
Just because you don’t believe it - doesn’t mean it’s not so.
Re: What size of motor to run a lathe
I agree with Steve, The motors you have sound like they would be under powered for your lathe. I have a 16" Hendey lathe that is currently powered by a 2 hp asian origin motor that I plan on swapping out to a three hp American made motor a friend gave me, The 2 hp just isn't cutting it when I want to hog material with this lathe.
Hal
Hal