OpenSCAD Falt-Screw library – optimized for FFF printing

An OpenSCAD screw library for screws that are especially optimized for the limitations of the FDM printing process.

Get the library on github: https://github.com/mechadense/scad-lib-FDMscrews

(alternative name:"flatscrew library")

Highly suggested is printing the screws sideways with parts of the screws chopped off (library supported).Tensile loads on the screws is now parallel to the printing layers.

This:
★ gives much stronger screws
★ allows printing without support
★ allows printing without retraction
★ (allows for fast printing with the default thread profiles)
Among the supported thread profiles are soft ones for fast printhead-jerk-less printability.
★ default thread profile is osculating quadratic
★ also very good is sinusoidal
★ there are a few more profiles available

Known problems:
Unfortunately the currently implemented triangulation method does not allow for
proper sawtooth, rectangular and steep trapezoidal profiles.
The triangulation scheme needs to be switched out for such steeper profiles.

Print Settings

Printer Brand: Ultimaker
Printer: Ultimaker Original
Rafts: No
Supports: No
Resolution: 0.2 or any
Infill: high
Filament: any PETG maybe – (avoid PLA/PHA) unpigmented or any

Notes:

When printed laying flat on the side (as suggested) then
⚝ no supports are needed
⚝ no retraction is needed

Suggestions:
⚝ More (3?) perimeters.
⚝ Alternating perimeter number. 
Making the infill interdigitate with the perimeters.

⚠ Warning:
I found that a non-pigmented PLA/PHA blend filament develops micro-cracks till rupture when highly loaded over longer periods of time. PETG may work better but I haven't tested that yet.

Post-Printing

When printed flat as suggested then
remove the eventual first-layer-squish-burr on the underside.
Tolerances for this pre-compiled example are pretty lenient.
If the nut on the thread is tight working it in manually can help a lot.
But if it's really tight than go over to github for the library,
adjust the tolerances recompile and reprint.

Category: Parts