Help me choose some depth micrometers

[AmericanMachinist]

you can get square gage blocks with a hole in the middle, those would work very well if calibration is needed. They come up on eBay from time to time.

Maybe use regular gage block (if already available) and just mic right up to the edge? Or even use a known-spec 123 block if its the best on hand? To get pretty close for hobbyist use, not certified for critical work.

 

[mattthemuppet2]

For sure those would all work. To be honest unless they've been hammered on or are rusty they'll probably be fine as is. Those holey gauge blocks are the bomb for this though