I been told that back before rotary phase converters were available, a lot of old timers that lived out in the boonies would run three phase equipment in their wood shops by making a static synchronous phase generator using a second junk three phase motor and connecting one winding that was out of phase with the drive motors enough to create the third leg.
I have no idea if this is allowed anymore, or what it does for power factor, motor heating, etc., but met a guy from Vermont probably 15 years ago that did just this in his woodshop.
Since this was probably once a fairly common practice, maybe you could find an old timer industrial electrician in your area to help you hammer out the details to do it safely.
