Specifying that threads be cut not formed
Specifying that threads be cut not formed
(OP)
I have a part with two 2-56 holes, in which screws tend to gall because they are catching the valley of the formed thread. I would like to ask the supplier to cut the threads. Other than adding a note. Does anyone know of guidelines for specifying that a thread be cut as opposed to formed?





RE: Specifying that threads be cut not formed
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RE: Specifying that threads be cut not formed
So you can add a note saying "THREADS INDICATED SHALL BE CUT NOT FORMED" or similar.
However, I'd double check you really have the right cause & effect before you do this. Fundamentally if correctly formed, cut or otherwise formed threads should not encounter the problem you're seeing over normal engagement lengths.
Have you inspected the threads with 'go gauge' or similar? If they are failing inspection then the parts don't meet the existing print - what makes you think this vendor will make them meet the new print?
Sounds like it may be a quality problem, not a drawing problem.
What is Engineering anyway: FAQ1088-1484: In layman terms, what is "engineering"?
RE: Specifying that threads be cut not formed
John Acosta, GDTP Senior Level
Manufacturing Engineering Tech