I run 1 1/2" bands on 19" tight belted wheels, I get long service and usually a dozen sharpening's before the band dives. When the band is ground down to 1 1/4" the problems start. Someone suggested the problem is my 1 1/2 guide rollers and a 1 1/4 band, thank you, I think that's the problem. Checked it and Shure enough the roller is extending one third of the way into the gullet. I have also noticed the inside teeth always seem to need more set. I'm a cheap old yankee but maybe I should be happy with a dozen grindings, snap a solute, and retire the band to the scrap pile. Sometimes we are blind to the simplest problems. Frank C.