For those needing to measure centerline thickness of slips:
I wanted to mention that Tim Britton sells Teclock Dial Calipers that are simply outstanding for this job, and seem to be tailor made for reed makers. The piston has a a wider rounded end that allows you to slide the slip from end, and w/o too much pressure from the spring loaded piston. It’s a precision instrument.
Contact me if you would like more info.