I have ran into that problem also, it seems everybody wants to add MMC to threads. I use threaded hole locators for measurements and report RFS. Since most of the engineers I have dealt with THINK MMC refers to to the minor diameter they think I can just stick a gage pin in the hole and measure the pin and viola, we have MMC. But what a few fail to realize is that unless specified, MMC comes from the actual pitch diameter. So unless you've got something magical up your sleeve it is very hard to add MMC to the PD.

We did an R&R on a 4 faced part each face having multiple threaded holes and came up with a very respectable 5%. We started from scratch each time the program was ran and the thread locators were used randomly in the holes.

Duane Wade
CMM Technician
TeleFlex Automotive, Inc
Pedals Division - Kendallville
301 W. Ohio St.
Kendallville, In. 46755
ph 219-349-1985 ext 3339
fax 219-349-1983