Parametric Flexible Z Coupler

thingiverse

This OpenSCAD file, named "Z_couple_Parametric.scad," is an alternative version of thing:5439. It was altered because the NEMA 17 stepper motors' shafts were 4mm instead of the usual 5mm. This file allows users to adjust outer diameter, two shaft diameters, spring section length, end section length, center section length, twists per spring, number of sides on the coupler (facets), and duty cycle of the spring (fraction of solid spring). The included STL file has specifications: spring height is 10mm, end height is 10mm, middle height is 2mm, coupler diameter is 30mm, it has five sides for coupler, threaded rod diameter equals to 23.5mm*25.4mm, motor shaft diameter is 4mm, twists in spring sections are two, the duty cycle of spring section is 0.75, and a fudge factor for ensuring shape overlaps is 0.1. The file can be printed with ABS or PLA, but ABS is expected to work better long term due to its durability against PLA's brittleness. It was printed with 90% infill and three shells for strength, but lower settings can also be tried. Kindly share the results for further reference.