[BlackICE1]

I was going to build an simple electronic tool setter for a lathe by just isolating a machined rod mounted in a the chuck and having the tool tips slow contact the rod completing a circuit and setting a X and Z location. After testing some of my tooling I found out that this won't work for everything as some of my coated inserts are non-conductive. Bummer. Anyway around this problem?

For milling tooling I can just use a switch since the tool's location only is needed in one axis, this won't work for X on a lathe.

[Eldon_Joh]

spring loaded piston pressing on a razor blade breaking an optical switch should be good to .001"

if you want to get fancy build a 10:1 mechanical advantage. should get you in the range of a tenth.