Master Wholesale President Blake Adsero demonstrates how to sharpen or reopen a diamond core bit to cut like new again. Blake uses a 60 Grit rubbing stone and drills at an angle at first then slowly moves the drill directly over the stone. Then rock back and forth to get the edges of the hole saw bit, and finally engage the motor in reverse and rock back and forth for 10 to 20 seconds. Your diamond hole saw blade should cut like new again. #masterwholesale #diamondcoredrillbit #diamondcorebit #corebitsharpening #reopencorebit