I had occasion the other day to contemplate milling a smallish flat bit of metal to reduce its thickness a bit. it's L shaped and roughly 2" on a side, and about 3mm thick.
Since holing it in the drill vice is obviously not going to work, and I don't have a magnetic chuck (and in any case it's not ferrous), how do you go about holding it on the machine so that it's flat, supported and stays there to be milled?