Thread Pitch and Min number of Threads

[Radius1]

Hello Eng Tips,

Does a thread pitch of 1 mean that for example 1 thread per millimeter ?

So I I needed 10 threads, the depth would need to be at least 10 mm in depth ?

 

[JohnRBaker]

That's the way I would expect it to work.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:
UG/NX Museum:

The secret of life is not finding someone to live with
It's finding someone you can't live without

 

[Scuka]

Nope, doesn't work that way.

Metric threads specify the diameter and pitch, not threads per inch.

M10x1.5 means M10 thread with 1.5 mm pitch, i.e. 1.5 mm distance between threads. That's different than 1.5 threads per millimeter.

'Murican threads specify the diameter and threads per inch. So 3/8" - 16 is a 3/8" diameter thread with 16 threads per inch.

 

[3DDave]

To get 10 turns of a 1 mm pitch thread needs at least 10 millimeters. For a hole, it may require another 1mm for the incomplete start thread from a countersink and another 1-3 millimeters at the bottom of the hole depending on the condition/design of the business end of the tap.

To clarify on the "doesn't work that way" the 1 mm pitch means 1 mm per thread, not 1 thread per millimeter. For unity the values are the same, but for any other pitch it does matter.