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skeet
08-19-2011, 12:25 AM
I know nothing about electricity..actually hate working with it. The question is..

I just bought an older but very nice Southbend Lathe..Got all the bells and whistles..but it had a 1/2 horse 220 3 phase motor . I do not have 3 phase power on the ranch .I know they make solid state phase converters but they only give you about 2/3s of rated power. I will not be using the lathe for extended periods..so the question is..will a phase converter be ok or should I change the motor out for a single phase??..Motor will cost approx 200..phase converter about 80 bucks..wish I understood electric. I now have 4 lathes The Southbend, have a small Craftsman 6x18 for turning small items and a nice little Unimat that is going down the road soon. Haven't used it in years. I also have a Craftsman(Atlas) Commercial 12 inch back east at a friends place. Think I will even sell the small Craftsman now that I have this Southbend. Anyway any help on that 3 phase stuff will be a big help

powell&hyde
08-19-2011, 09:58 AM
Change the motor out for a single phase motor, than you have full rated power available.

skeet
08-19-2011, 10:58 AM
The only problem changing the motor out entails is finding a motor with the right frame mounting..oh and finding a reversible motor.. Lathe motors are kinda different I think.. But Grainger may have them what i need....

Rapier
08-19-2011, 01:44 PM
Skeet,
The reversible single phase are all over $300 at Granger. I bought a converter for my knee mill. I will buy a new lathe and get a single for it unless I get a 3 phase deal then I will put a converter on it also.

One thing about the net, you should be able to find instructions pretty easily if you need help with the hookup.
Ed

skeet
08-19-2011, 02:18 PM
Thanks for the info Ed..

Did you put a solid state converter or a rotary? If I go with a solid state should I go one step higher on the converter..meaning instead of a 1/3 to 3/4 horse should I go with 3/4 to one horse converter?? I really don't understand that stuff.

powell&hyde
08-19-2011, 04:10 PM
Skeet, if you have a tig or spot welder, you can easily transfer the frame off your old 3phase motor to your single phase motor.

Larryjk
08-19-2011, 06:22 PM
I have been running a 12 inch lathe and vertical mill each on a separate state converter. I have never had a power problem. When you are turning down stock is when you would notice if power was a problem. I have never had a problem. Used to run a 15 " Shelton lathe on the same converter I am using on the mill. This started over 20 years ago.

Rapier
08-21-2011, 07:53 AM
Skeet,
I do not have my equipment installed yet, as my shop building at the farm is not built yet. But my plans are completed and my selected contractor has left the area and I am looking for a new builder. The converter came with the mill, a used setup. It is probably a rotary, being an older unit and I did not know enough to even know the difference, frankly. I am learning though. My main power line, goes across my property, is ¼ mile from the driveway and the shop will be over 500 feet from the drive/road intersection. No doubt our co-op will charge for a 3 phase and may not install it to start with. The part for concern is they have a very poor history of dropping power at various times of the day and I plan a full house 25KW generator on natural gas just for that exact reason.

This site has an explanation of the different types of converters. I would take a light duty motor (.5 hp) explanation to be a lot different than a heavy duty motor like a 7.5 to 10 hp that is used as an example for their product. So I would simply use the data for info.

http://www.phaseperfect.com/phasewhitepaper.htm

This is a site that allows you to put in data that will search for your specific converter need:

http://www.driveswarehouse.com/Drives/AC+Drives/Phase+Converter+VFD.htm

skeet
08-22-2011, 06:40 PM
Well I did quite a bit of research and think I am going to go with a static converter. I found a dual range one good for 1/3 to 3/4 horse on the low side and 3/4 to 1 1/2 on the high side. Cost is 109 bucks delivered And I found a one horse 3 phase drill press that i can buy at a good price..run either with that thing.. Now for a small milling machine...uh uh..then I gotta learn how to run it

skeet
08-22-2011, 07:03 PM
Ya know..it seems really funny..looked all over for a nice Lathe for quite a while..bought one and now I have offers to sell me one comin out my ears.. Guy has a really nice SouthBend Heavy ten with a bunch of tooling for a fair but still expensive price..1600..and I have another offer to sell me an as new Craftsman Commercial(Atlas) 12 in with all the Bells and whistles for a thousand..both single phase..and I had bid on another Graftsman commercial with all kinds of stuff with it..Reserve wasn't met and now the guy has lowered the reserve ...alot... and now I am the high bidder. Am going to withdraw my bid i think..Don't need more'n 2 or 3 LOL!!

fabsroman
09-08-2011, 12:39 PM
Ya know..it seems really funny..looked all over for a nice Lathe for quite a while..bought one and now I have offers to sell me one comin out my ears.. Guy has a really nice SouthBend Heavy ten with a bunch of tooling for a fair but still expensive price..1600..and I have another offer to sell me an as new Craftsman Commercial(Atlas) 12 in with all the Bells and whistles for a thousand..both single phase..and I had bid on another Graftsman commercial with all kinds of stuff with it..Reserve wasn't met and now the guy has lowered the reserve ...alot... and now I am the high bidder. Am going to withdraw my bid i think..Don't need more'n 2 or 3 LOL!!

That is the way it goes. When you don't have something and want it, you cannot find it for a decent price. As soon as you have it, you can find plenty of it and cheap. A year after I bought my SBE, I was at the gun shop looking at a new gun and a guy wanted to sell his 1 year old SBE for $850 that was just like mine. Mind you, I had just paid $1,350 for mine brand new the year before. I passed the deal on to a friend and he bought it right away. He wanted a gun like mine until he saw the price tag on it new. He even had to stretch to buy that used SBE, but he loved it once he got it.

My list of wants has gotten a lot longer since we bought this house.