I traded for a minty Airco PhaseArc 350 mig welder last week with the
idea of maybe either being able to run it from a 5hp rotary phase
converter that I run my machine tools in my hobby shop with, or
selling it and purchasing a single phase machine.

Yesterday morning, I wired it up, using a 12/3 100' extension cord. I
figured I might as well try it worst case. (yes, I know..no safety
ground..shrug)

To make a long story short, it worked beautifuly. I spent about 5
minutes doing nothing but filling the top of a chunk of plate with a
6" continious back and forth bead of .035 wire, thinking that
something should get warm, or reach welding time % and it just kept
feeding and burning with that marvelous frying bacon sound, with good
puddle and penetration. I sectioned a chunk of the plate with an
abrasive saw and penetration was very good.

I then loaded a spool of .045 dual shield and did the same thing. It
took a fair amount more volts of course, and every thing worked fine.
I do have an issue with the Arcomatic lV wire feeder with the bigger
wire, as its not the proper feed roller for that size I dont
think..but all in all it burned well. The .035 burned best with the
meter settings at 21-22 volts and the welding output amp meter showed
around 100-125 amps during welding. Today Ill put a amp meter on the
line and see what the actual draw on the RPC is
Everything remained nice and cool, even the horrendously long and
undersized extension cord remained cool.

A Rotary Phase converter is easy to build, lots of plans on the net,
and they can be built quite cheaply.

So picking up a decent commercial 3ph mig welder cheaply (since lots
of folks are going to inverter machines) is a pretty viable way to get
a decent commercial grade MIG welder and being able to run it on
single phase home power.

I dont have any 3ph stick or tig machines, so I cannot give any data
on what one of those would take to run.

YMMV of course.

Gunner, off to weld up a cart for that big ******* G

It's better to be a red person in a blue state
than a blue person in a red state. As a red
person, if your blue neighbors turn into a mob
at least you have a gun to protect yourself.
As a blue person, your only hope is to appease
the red mob with herbal tea and marinated tofu.

(Phil Garding)