OpenSCAD NPT / tsmthread 0.4

This is a fast and flexible thread-profile generator for OpenSCAD.
* It makes frugal, consistent, sound meshes.
* It makes undistorted NPT theads!
* It obeys $fs/$fa/$fn.
* It uses arbitrary profiles - i.e. the difference between UTS and ACME is a variable.
* It does multi-start threads.
* It can compensate for printing steep pitches like ACME.

As usual, all this stuff also lives on my site: http://burningsmell.org/3d/lib/tsmthread/

TL/DR
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// 5/8" 11TPI imperial t