This is one of the few pet peeve's I have about locks today. All of the lock assembler's seem to press the cock onto the tumbler shaft with some form of hydraulic press. I guess this saves a few minutes in the lock assembly process. It sure does add time to the disassembly process and adds a opportunity for the builder to damage a tumbler. If you look at the square notch in the cock after it's initial removal you can see the rolled up metal from the forced fit by the assembler. Now this does make for a tight fit but it also requires unnecessary force to remove the cock from the tumbler.
After I remove the cock from the tumbler, I take a square jeweler's file and remove the rolled up burr from the square notch in the cock. I then file a very slight taper in the square notch of the cock. This allows me to remove the cock with minimal force and to seat the cock onto the tumbler with minimal force. All of this takes about five minutes. I guess that is to much time for the assembler to take, after all 5 minutes does add up to an hour after 12 locks.
I also use one of the wooden blocks with the hole for the tumbler to fit down into and a good punch, but that job still worries me every time I do it.
