tsmthread v4

TL/DR,

include <tsmthread4.scad>;
// 4-start TR20x4 leadscrew, 15mm long
tsmthread(DMAJ=20, L=15, STARTS=4, PITCH=4, PR=THREAD_TRAP);

This is a fast and flexible thread-profile generator for OpenSCAD.

• It makes frugal, consistent, sound meshes.
• It makes undistorted, properly-tapered 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.

Also see /lib/dimensions for lots of references on screw thread profiles.

Known limitations:

• It cannot make concave profiles.

 Name                           Last modified      Size  Description
 Parent Directory                                    -   
 TR11X2-diagram.jpg             2019-02-01 19:19   15K  tsmthread4-mk5-acme.stl makes one of these
 3-8-10-flange-diagram.jpg      2019-02-01 19:19   27K  tsmthread4-mk5-acme.stl makes one of these
 thread-compensation.png        2019-01-30 04:38   15K  What comp_thread does - better fit with less undersize
 calibration.jpg                2019-01-30 04:38  296K  What a mess.
 tsmthread4-mk5-print.stl       2019-01-30 04:38  786K  Example print, household object threads
 tsmthread4-mk5-acme.stl        2019-01-30 04:38  1.1M  Example print, TR11x2 and 3/8-10 leadscrews
 tsmthread4-mk5-npt.stl         2019-01-30 04:38  2.4M  Example print, 1 1/2, 1 1/4 NPT fittings
 npt-profile.png                2019-01-30 04:38   14K  Calculated profile vs perfect triangles
 drillbit.png                   2019-01-30 04:38   44K  An example of an impossible thread profile
 tsmthread4.scad                2019-01-30 04:38   31K  
 profile-test.jpg               2019-01-29 20:53   43K  
 cpu-killer.png                 2019-01-30 16:34   16K  
 all-threads.jpg                2019-01-29 20:53   96K