This creation was mainly to try what is possible with a 3d printer.
First I made a single long hair pin but it was too short for my purpose and maybe to thin in the end.
Made a second on a double with threads M6x1 to connect them both.
Why this print ... good question but this is a replacement hairpin. This pulls the hair thru a silicone tube which rolls up the hair so you get curls

Print instructions

This g-code are with support from the buildplate.
After printing, the screw was cleaned with a thread die. Before the cleaning the thread went 5 turn before get stuck. But after cleaning it was possible to screw all the way and the loops lined up.

There are to builds in this section.

Both pins are made in solidworks the pin are made with helix path then sweep .... the long hair pin I went with a taper on the helix.

The thread are made with built in command "Thread.." the hole was 5,1mm and bolt was 4,9mm ... this to create a tolerans