Necklace with Closure

This is a sturdier version of thing:177361 Christmas Garlands. A closure has been added. The individual beads are elongated milled coins - see thing:27934 Coins or Pendants. The closure is a coarse screw and nut which takes advantage of the fact that the beads are free to rotate. It uses threads.scad available from http://dkprojects.net/openscad-threads/

Stl files are:

short_bead.stl
long_bead.stl
clasp_top.stl
clasp_bottom.stl

OpenSCAD code is included.