Ok first off i don't have sanding mandrels. I know that is one option however, I have made probably 20 or 30 sets without issue until now. Im using a super glue finish. I have tried leaving them on my drive pins and then screwing them together after finishing. I have tried leaving them together then cutting apart after finish is done. I tried finishing them separately unused drive pins smaller than the outside diameter, then facing them off. No matter what i do, I can't seem to stop the finish from pealing away from the wood at the joint. Any ideas short of sanding mandrels? Unless some has a set for sale for cheap. This will be my fourth time finishing them. Two of the first three attempts are in the pictures