Quote Originally Posted by JohnHaine View Post
Chaz, I have made something based on the "touch plate" concept used for mill Z homing.
Click image for larger version. 

Name:	pic_5_cmp.jpg 
Views:	357 
Size:	18.8 KB 
ID:	24073
(I hope that works!)
Repeatability seems to be better than 10 microns, and in conjunction with my tool setter on my first trial of homing/applying set tool offset/turning I achieved indicated microm accuracy on diameter. This cost nothing to make, it's essentially a bit of PCB laminated on to 6mm of tufnol superglued to the apron front. Obviously there are issues of wear and tarnishing so I intend to upgrade it with one where the contact surface is beryllium copper.
Thanks, I had though of similar - this is the way that we deal with milling offsets, so no reason why it wont work on a Lathe. Ill try the switch from audioandy (Thank you) first and go from there.

Thanks for the other suggestion Gary.