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I finished my 3D Printable screw design! Excellent print ability, reliable for simple use, though the head is prone to strip... can't win them all.
(programming.dev)
If you wanna print it yourself, the model is here: https://www.printables.com/model/1348194-4n-threaded-flat-head-screws-and-nuts-10-32-equiva
Design to be a drop in replacement for 10-32 screws with a much, much higher pitch. These screws are extremely easy to print, is reliable enough that it can hold some weight.
If you wanna print this yourself, you need to make sure that the screw is sideways, so if it breaks it's no on the layer lines.
Using them in my own prints which had metal screws and they are holding quiet well.
Having single pointed 3"-4 Buttress threads on a manual lathe for punch presses more than once and hand grinding the tool bit from 1/2" x 1" HSS, I still have some PTSD over that thread form. But hey, if you are looking to make breaching for a 16" Navel Rifle, it's really the only game in town......
As a toolmaker, I have seen Buttress threads used in only 3 places. Large artillery breaching, punch press ball screws, and VERY high end, (read expensive), machinist clamps. I own a pair I picked up at an auction 30 years ago in a bucket of "junk". I think they were made by another machinist for personal use.
Edit to add: Buttress threads are directional. They can be either left or right. The choice being totally dependent the direction of the force applied to the threads. The perpendicular edge is the strong part. And the direction must always be called out.
I worked at a shop that made large hydraulic cylinders and some of them used buttress threads.
I've seen hydraulic cylinders up to a mere 150 tons, but they both used vee threads. But those cylinders can had far,far bigger than that. That would be a very good application of buttress threads. Much like the balls screws on a punch press. Lots of force in one direction.