Engineers specify/design--to industry and/or company standards or run the risk of being misinterpreted if one exercises otherwise and it is then that machinists oftentimes come back with questions when ideally there should not be any.
Machinists/fabricators interpret engineers' works and...
Just reaffirming Kenat's first paragraph, or actually, the entire thought for that matter, that it is a matter of compliance--to what is set forth in POs/contracts.
Would caution, however, on Cockroach's approach. Hearing no complaints from a machinist would explain the adequateness of a spec...
Ted / Hydtools,
Just as in that one school's standards (earlier link) pointing to the "last operation," however opposite is your approach, it's a good/valid point. Again, not necessarily is there an incorrect way to do it.
Associating either the minor or major diameter with thread inspection...
Or another way to look at it is IF there is no governing body/standard (e.g. ANSI) specific about such detail, consideration is to be taken if the (educational) institution or (manufacturing) company has its own by which a drawing detail is to conform. Otherwise, either way should be acceptable...
Link
Link
Could not find international standards but the two links above provide a good start ESPECIALLY the second one (from "wisc.edu")which, on page 8, reflects a practical approach wherein an arrow points to, or lies on, the last operation performed. Reference to thread callouts in the...
Facing the circular profile of an internal thread on a detail drawing, to which line, (A) the solid line minor diameter or (B) the hidden line major diameter, should a thread callout/dimension arrow lie on?
Early in career, I dimensioned to the solid line by the basic idea of not dimensioning...
