request to learn more about advantages of the library
karan-ta opened this issue · comments
Hello
could you please tell me what are the constraints of fdm printing while printing bolts , nuts ?
i request to learn more about this library as compared to bosl or threadlib for nuts, bolts.
The main constraints of FDM printing while printing bolts are …
★ … either usually unacceptable low bolt strength for vertically printed bolts due to low inter-layer adhesion in that direction (at least for most filament materials). So let's just not do that.
★ … or impossibility of too low screw pitch for horizontally printed bolts of smaller diameter.
The latter one is due to the nozzle orifice diameter typically being 0.4mm which is quite a bit bigger than minimum layer thicknesses e.g. 0.05mm (= 50µm) for really high resolution prints.
When printed sidewards and in case of smaller screws the existing standards
that where designed for manufacture-by-lathe (like e.g. metric)
have such a low pitch, that the profile is blown out by nozzle-orifice-diameter.
(Mathematically it's a folding operation.)
This library …
★ … does not follow existing (typically low pitch) standards that were designed for manufacture-by-lathe.
To avert aforementioned issue.
★ … has an integrated option to cut off the bolts sides, strongly advocating the idea of sideward-bolt-printing.
★ … features default profiles (sinusoidal, quadratic) that pose low jerk-loads on the print-head despite the needed zig-zag motion for sideward printed bolts. This is beneficial for fast and still accurate prints.
Additional (potential) benefits of printing sidewards with cut off sides are:
★ No layer cool-down time issues for thin bolts due to a much bigger cross-section.
★ As a bonus: The cutoff allows for using the screws to lock rotational degrees of freedom together. E.g. in hinges.
★ Arbitrary profile steepness (not to confuse with pitch) is possible, since
steep profiles make no overhangs when laying sidewards.
In the extreme of profile steepness there are the square-wave profiles. Printing these should be easily possible, BUT …
Unfortunately the current sub-ideal triangulation method throws a wrench in that potential benefit.
This still needs fixing by swapping out the triangulation method as a whole.
Regarding the nuts:
★ These are still printed vertically.
★ These are rather non-problematic allowing for surprisingly severe overhangs from profile steepness.
Also the choice of high pitch lessens the severity of overhangs form steep profiles a bit.
PS: This refers to:
https://github.com/mechadense/scad-lib-FDMscrews