we have a part with a tru pos of .002" to a 10-32 thread. Ridiculously close, yes, but it's on the drawing.
i am checking it with a 2x20 no ext. using the pitch feature in auto circle.
at first we had a problem with this repeating part to part. everyone assumed it was the cmm, as usual.
found out they were only drilling the hole then thread milling.
once they started using an end mill to bring the minor dia. to size and a more accurate location the cmm has not had any problems with inspecting the .002" tru pos.
may not need the end mill due to thread milling, because i agree with an earlier statement that unless specified the tru pos is from the pitch. but difficult to check to the pitch.
point is, using the pitch feature when checking a thread with a Spherical probe has worked very well for us.
we have a part with a tru pos of .002" to a 10-32 thread. Ridiculously close, yes, but it's on the drawing.
i am checking it with a 2x20 no ext. using the pitch feature in auto circle.
at first we had a problem with this repeating part to part. everyone assumed it was the cmm, as usual.
found out they were only drilling the hole then thread milling.
once they started using an end mill to bring the minor dia. to size and a more accurate location the cmm has not had any problems with inspecting the .002" tru pos.
may not need the end mill due to thread milling, because i agree with an earlier statement that unless specified the tru pos is from the pitch. but difficult to check to the pitch.
point is, using the pitch feature when checking a thread with a Spherical probe has worked very well for us.
