3450 x pi x 3" drum= 2700sfm, but I liken the speed to a grinder , I use only high quality 3M belts and they last me a long time, Im only a home gamer. with a course belt it cuts quickly and your part does not get too hot, approx 5100 SFM. A 6" grinding wheel =5400 SFM running at 3450rpm. for...