Re: how much torque on 4 jaw chuck
If I may, please let me share a little bit of info that most already know. This is not new, but as long as someone doesn't know, then it's new to them. I use a three jaw adjust true chuck which most of us already have. I use a piece of #6 or 4 bare copper wire between the jaws and barrel. This help for easy pivoting. Now tighten down to a set torque that you're happy with on the three jaw. When you need to make adjustments, use the four bolts that move the whole chuck in the desired direction. This is smoother than a four jaw for me. No need to keep the oposite bolt/screw tight, as the bolts on the face of the chuck keep it tight enough to the backing plate. You will never overtighten this way for those who are worried about it. The oposing screw can be snugged up once you have what you need. Watch the needle on the indicator while snugging. It should not move. Hope this helps those that are looking for different way of aligning the bore for work.
BTW, thank you X, but I'm really nothing special. I actually look up to all of you guys that do this to keep me up to date on all the new methods you discover. Some of you I will never be able to be because I can't justify buing a 3 millon pound CNC machine to do hobby work, and occational jobs for my local area shooters. I do admire the CNC machines though. I wish I even knew how to work one. Again, thank you.