it definitely could be the compounding then, also i use a 65A EPDM to cover my rollers so there could be a huge difference there. what material are you using?
You need to slow down the traverse speed of the grinder very slow. I am not sure of the exact numbers, but for example on my Cincinnati grinder an 8" long face roller it takes about 3-4 minutes for the grinder to go across the whole face. You will need to look through a magnifying glass to see...
