Zradix, I am far from an expert but I have a 3" drum on my drill press and the only sleeves I could find for it were 36 grit I believe. The bow I built has a 72# pull and it hasn't come apart yet. Ive been shooting it daily for the last week. It may have even given it a stronger bond. The rougher sand paper probably gave the epoxy more surface area to adhear to.