ORIGINAL: Ttowntoolman
I agree with the tool collet as that is the exact same unit I use to pinch my stuff. Been using it for a couple of years now. My problem is, WHERE does the material go? You cannot take a perfect circle and squeeze it and expect it to be round. You are displacing material to somewhere where does it go? That is my problem, it just does not add up in theory. I still use the pinch theory, but would like to explore other things that actually make sense.
You are only decreasing the ID by about .0001, so the material you are not displacing all that much material. You do change the shape a little, but that's why you have to break your engine in again.