How to utilize three-phase electrical in residential garage for antique shop equipment
There are various types of phase converters available. There are do-it-yourself methods involving an "idler" three-phase motor and some capacitors. There are variable frequency drives (VFDs) that convert 230 V, single-phase to 230 V, 3-phase and also provide motor speed control. There are also VFDs that convert 120 V single-phase to 230 V, 3-phase, but they would probably only do 2 or 3 Hp. There are do-it-yourself methods that require only capacitors connected to the motors that you have, but they will reduce the power capability of your motors. It is probably best to look for recommendations on metal and wood shop hobbyist sites.