On Dec 19, 2:38*pm, Jim Wilkins wrote:

I just remembered that when I had to move the head I centered a small
hole under it first and then afterwards located the head on that hole
with a center finder. The center finder shank fits in a collet when
the head is down and a drill chuck when it's up, effectively adding
the height of the chuck to the accurate Z axis range of the machine.

jsw

Simple, no laser required.

Dan