05-30-2012, 07:44 AM
Dave, it does work on nearly any material. Unless the hardness approaches that of the ball, or the finish is already too smooth in the hole, it works. It is one method used to lock in and resize valve guides on OHV engines. I used to run a "head shop" and did a few rebuilds of heads that required sleeved guides. Those liners were bronze, but sine it worked on them, I tried it on steel parts other places. I like it because you can get BB's of most sizes pretty cheap. In the head work, I used an air hammer to drive them through. As long as the hole was straight to begin with, the liners came out straight even driving a ball through. For other work, I prefer to press it through rather than drive it through though.