Often I found myself needing thumbscrews on my projects, and since M3-M8 are my most common used sizes i deceided to make myself some:

The thumbscrews are designed for socket head screws and use a nut in the compartment on the underside to connect them securely together. Make sure to tighten them as well as possible beforehand. If you want extra strong bond between the bolt and the nut you can apply some threadlocker or similar.

(I recommend to use nylock nuts)

Depending on your printer you might need supports in the cavity that holds the nut for the normal/first version, but it have been printed fine without if you place the nut side up.

There is also now a knurled version here for those who prefer that:

My collection of other tools and related items can be found here

I have also taken inspiration from JW693Ds suggestion and added a version with a punch trough layer of bridging if you have problems printing the normal one without support. That version is to be printed with the round hole facing the buildplate.

It uses uses only about 1 gram of filament and prints in 10-15 minutes dependin on size . (About 25 minutes ish total if printing the spacer at the same time)

I have also included a spacer for where that is needed, or to simply hide a bit of threads. The length of this can be adjusted by changing the prints Z-size in your slicer.

Happy Printing, and if you like it, please post a make, as that is always appreciated :D

(If you need other sizes, let me know :) )

Check out my other models here

Changelog August 18th 2022:

M8 added.

Changelog: May 20th 2022: Changed the tolerance of the M4 Thumbscrew center hole, as it was to small.

Changelog: May 23 2022: Added versions with punch-trough bridging layer.