12mm rod holder/clamp m6

The hole in the middle is exacly 12mm. Depending on your printer and filament type you might need to put short section of 12mm steel rod in your drill and friction melt the plastic to exact dimensions. This way it has perfect snug fit and offers great stability.

The captive nut might need some enouragment to get in in the form of a hammer.

All holes are m6.

If you encounter problems with breakage please write a comment and I will make a new version.