Hello,

I am trying to perfect my tension-set rings which are essentially quite simple and taken from Cogswell's book: 2.5mm silver wire, twisted and hammered to become hard, formed around a mandrel.

However, I am having trouble cutting a seat to hold the stones. On the last one I made, I cheated and cut across the silver using a needle file, but this obviously means that the stone has plenty of room to move.

I have a bush burr but it "skids" across the silver when I try to cut into it. Does anyone have any tips about where I'm going wrong, please?