Nice. Can you make them a little less polished so the threads are easier to see? Maybe more like this.
I could, but then they would wear out faster from the extra friction.
Just as you probably cringe when you see someone abuse a nice piece of wood, it really hurts me to roughen up a nice piece of precision ground 303 stainless or 6150 alloy
Question there . . Will that print in 3D ?
I am guessing it has to be standing up right to print right ?
Standing it upright is trivial.
Yes, but it may not print very well at all on some printers.
It depends … you could also slice it down the middle and print it laying flat as two half-threaded half-cylinders and glue them together when you’re done. As @DaveR says, standing it upright is trivial … just because it’s a “solid”, which generally means it can be “printed”, doesn’t mean that it will necessarily be successful or acceptable. It all depends on the actual geometry, size, and print medium involved. Most of my 3D printing designs start with the print media and the resolution of the printer and then I work backwards to make sure that the final design is printable (at least in theory).