Hello All,
The item to be sentenced is diam 6.5 max(mm). What should the female gauge size be, 6.5 -0.01?
Regards
Confused here - Your title indicates a "plug gage" and then you ask about a "female" gage size. Forgive me if I've been out of the shop too long, but a "female gage sounds more like a "ring" gage than a "Plug" gage.
Are you trying to gage an internal dia or an external dia?
Anyway - Lets see if we can answer your concern.
Lets assume you are making an hole that you wish to check with a plug gage. The max allowable on the hole is 6.5 mm. So you wish to make a plug gage that will tell you if the hole is oversize. The gage needs to NOT go into a hole at 6.5 mm but will go into a hole that is 6.51. In this case, the gage can be made at 6.5 mm.
O the other hand if you are gaging an external dia with a max allowable dia of 6.5 mm then the ring gage needs to be slightly larger, say 6.51 mm.
If the gage is made at the same size as the dim, you have an "interferance fit" or "line to line" fit and this would cause/allow some good parts to be rejected.
Does this help?
James