Osborn Round Abrasive Cup Brush

Osborn cup effectiveness

this is my first use of an Osborn Cup; it is said to be useful for refreshing, cleaning log surfaces. I was not impressed with its effectiveness: I used it on a variable speed angle grinder. It will not do what I need to clean interior log surfaces. Instead I'm using a course grit sand disc on the angle grinder and a 7 inch disc on a variable speed polisher: those remove the degraded log surface much better. with the Osborn brush, if I dwell too long to try to remove surface material, friction heat occurs and stains the wood surface.