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Craig Zettle
05-15-2006, 4:26 PM
I saw a 3 phase shaper on ebay and the seller said he is running it on 220 house current with a 60 dollar converter. Anybody ever heard of this? Sounds too cheap to me, but I never delved in to converting 3 phase to 1 phase. (5 hp motor, BTW)

Carl Eyman
05-15-2006, 4:54 PM
By all means it can be done. I don't know about a 5 hp converter for $60, but I ran a piece of equipment with 3 3ph fractional hp motors with a $150 +/- converter very successfully. Around 5 hp though you begin to need a rotary converter and that gets a little more expensive.

Alex Shanku
05-15-2006, 5:02 PM
Craig,

Dev has been very helpful and pointed me in the right direction to learn more about phase converters.

Check these sites:
http://home.att.net/~waterfront-woods/Articles/phaseconverter.htm

and

http://www.metalwebnews.com/howto/ph-conv/ph-conv.html

Rob Russell
05-15-2006, 5:02 PM
If you're a good scrounger and have access to industrial surplus, you might be able to build a very basic rotary phase convertor for about $60. The seller may also have been lucky enough to find a static phase convertor cheap, although the 5 HP shaper would only produce about 2.5 HP running off of the static.

Steve Clardy
05-15-2006, 5:05 PM
I'm running a 5h rotary, and a 7hp static box.
No problems

Steven Evans
05-15-2006, 5:42 PM
Well, I have no idea about a 60.00 solution but I do know about more expensive options. I have a 7.5HP Kay Industries rotary. Basic model about 1300.00. My model with mag switch, fuses remote control etc.. was about 1900.00.

chester stidham
05-16-2006, 4:31 AM
sounds cheeper to just buy a new motor one less item to worry about.:rolleyes:

Mac McAtee
05-16-2006, 7:45 AM
Did you ask if the converter goes with the machine purchase? Also ask where to buy a $60 converter?

Eric Commarato
05-16-2006, 2:00 PM
Craig,

I am running a 5 HP Tannewitz J-250 with a rotary phase converter on residential 240V power. I purchased a 10 HP phase converter kit from a company that took me about 2-3 hours to assemble. The kit was around 80 bucks shipped, all USA made parts. You will have to buy a Hoffman type electrical box to mount all of the components in. Since is it a rotary type converter, you will need a 3 phase idler motor. I bought a used Baldor 7.5 hp motor from a local motor shop for 100 bucks. I have been running this setup for about 2 years now with no problems, and the Tanny could probably cut through 1" steel plate...hee hee.

Good Luck and always use care with electricity as it can bite you.

Eric

Dev Emch
05-17-2006, 3:59 AM
At the last auction i went to, they had a basket of motors up for bid. A real box full. I saw 5, 10, 20 and even one 40 hp motors in this group. One OWWM guy bought a 10 hp baldor for $30 bucks from the guy who bought the basket of motors. So 60 bucks is assuming a bunch of freebies but it can be done if you know where to look.

Bruce Wrenn
05-17-2006, 11:55 PM
In our area, we go to salvage yard and buy motors BY THE POUND. A couple years back, my neighbor bought two- 3 HP to build rotary converter for $20.00. This worked out to 15 cents per pound. With recent increases in price of all metals, expect ot pay more. Most three phase motors are in salvage yard due to machine being junked, or bad bearings. Typical replacement bearings are less than $30.00 for both ends of shaft. Building a rotary converter isn't difficult, hardest part is getting idler to spin. We used a single phase dryer motor, with a "special" terminal that has voltage present when up to speed. This was used to ingage relay to supply power to idler. The most expensive items were the two fused disconnects from borg.