Photo Equipment Screws

1/4'' UNC
one is 3mm unthreaded then 6mm threaded
the other is 25mm threaded

I made a test-print with a crazy outer layer height of 25 micron -yes- 0.025mm. The print worked but there was some waving reducing resolution and making the surface rough. Nevertheless it turned out very usable and especially sturdy against breakage through sideward bending.