I looked up SFPM and then checked out the greaseless compound at Caswell. Didn't see anything that said what is recommended as far as SFPM with there compounds. But I'm guessing you all have figured this out already. And 1700RPM with 4" wheel is what is needed. Unless some money drops in my lap in the next couple weeks I don't think I'll be buying a Caswell. Just too much of an investment for something that is not going to be used much at all. I'll have to look for other options, unfortunately. I'd love to have the best in tools but its just not feasible for my use.

I'll keep looking around to see if I can find something a bit cheaper and try for the 1700rpm's. Bummer. I hate to settle for something less! Thanks for the information and letting me know what is best for the job.