romoshka
Plastic
- Joined
- Jun 9, 2005
- Location
- Upstate, SC
OK, I'm great with fractured bones and joint related issues, am school trained machinist (fully qualified to destroy a perfectly good chunk of steel) but I am hopelessly lost in the world of electricity and hence have refitted all of my machines with single phase motors. But the vintage Reid surface grinder that has sat in the corner for several years is begging to be brought into service and so I am being forced to build a PRC. I have 2 questions.
First - while many, but not all, of the various authors have recommend an idler motor of at least 1.5X the machine motor, given the extreme low load on a surface grinder motor why can I not use the 1HP 3Ph motor I have on hand.
Secondly, in the interest of $$ I would prefer to build something along the lines of Jim's RPC with a small motor to start the idler but would like (I think) to add enough electronic "stuff" to get balanced voltage. The fellow I bought the grinder from had a simple RPC running it and he used a rope to start the idler running ala old lawnmower technique. I did not pay much attention to the RPC as I thought I would change the motor - now I understand grinder motors are balanced motors and proprietary in construction hence not easily retrofitted with a single phase motor.
While I have read several of the articles on various websites I am still lost. I think all I need is a capacitor (or 2) and resistor. I'm begging here for a bit of hand holding and steerage.
First - while many, but not all, of the various authors have recommend an idler motor of at least 1.5X the machine motor, given the extreme low load on a surface grinder motor why can I not use the 1HP 3Ph motor I have on hand.
Secondly, in the interest of $$ I would prefer to build something along the lines of Jim's RPC with a small motor to start the idler but would like (I think) to add enough electronic "stuff" to get balanced voltage. The fellow I bought the grinder from had a simple RPC running it and he used a rope to start the idler running ala old lawnmower technique. I did not pay much attention to the RPC as I thought I would change the motor - now I understand grinder motors are balanced motors and proprietary in construction hence not easily retrofitted with a single phase motor.
While I have read several of the articles on various websites I am still lost. I think all I need is a capacitor (or 2) and resistor. I'm begging here for a bit of hand holding and steerage.