Threaded fasteners, when installed and tightened, should protrude a distance of at least one thread beyond the top of the nut or plastic insert. Excessive protrusion should be avoided, particularly when necessary clearances, accessibility, and safety are important.

How much thread protrude from a nut?

How many threads should protrude through a nut in an optimal joint? The generally accepted answer is 1 to 3 threads. Most externally threaded fastener blanks are manufactured with a header point prior to thread rolling, which leaves the first 1 to 2 threads undersized for ease of assembly.

How many threads should be beyond the nut two minimum?

Industrial Fasteners Institute, Joe Greenslade, Director of Engineering Technology. “How Many Threads Should Be Beyond The Nut?. The answer is: A minimum of two thread pitches should extend beyond the top surface of the nut.”