DIYbanter - View Single Post

On 23 May 2006 07:16:15 -0700, wrote:

I recently bought a 3 phase 1 HP surface grinder. My original intention
was to replace the motor with a single phase unit. But the motor on the
grinder is closely integrated with the tool itself. I suspect that it
would be VERY expensive to take that approach.

So I'm looking at putting 3-phase power into the garage instead. Since
my shop is in my garage, I doubt that I could get the power company to
put in 3-phase power for any reasonable price. So I'm looking at
alternatives.

I ruled out static phase converters almost immediately.

But the choice between a rotary phase converter and a variable
frequency drive unit (VFD) isn't nearly so obvious. Each has good and
bad points - making the selection very difficult.

So, I'm asking you to help me choose. If you currently have or
previously had both types of units in your shop, which type would you
pick to power a 1 HP grinder?

A cheaply and quickly made RPC out of a 3hp motor. Rope start is very
doable if you are on the cheap. Or a 1/4hp anything motor for a pony.

There was a gent selling an RPC panel on Ebay..simply add a motor. A
friend bought one and it works very very well. I think it was $99 or
something at the time..or $199..dont recall. I believe he was located
in California.

You can also use a VFD for this operation. 1hp units are not
particualy expensive. Just lock out ALL speed change options.
Depending on the unit..a tiny number have shown some harmonics on the
work piece..but I regularly use VFDs where finish is critical..and
note no issues with nearly all VFDs

Gunner

"If thy pride is sorely vexed when others disparage your offering, be
as lamb's wool is to cold rain and the Gore-tex of Odin's raiment
is to gull**** in the gale, for thy angst shall vex them not at
all. Yea, they shall scorn thee all the more. Rejoice in
sharing what you have to share without expectation of adoration,
knowing that sharing your treasure does not diminish your treasure
but enriches it."

- Onni 1:33