Hex Nut Covers 5/16 in-18 thread
thingiverse
I created custom covers for the 5/16 hex nuts to conceal them, and both top and bottom screw in seamlessly. The depth of the hex head is precisely 2mm, so if you're planning to place your spinner on a tabletop, I recommend adding extra thickness to the cap. I designed the bolts and rods using OpenSCAD and referenced NUT JOB (https://www.thingiverse.com/thing:193647) for guidance. After numerous trials and conversions from metric to SAE measurements, I was finally satisfied with the outcome. This design should meet your needs; please let me know if it does.
With this file you will be able to print Hex Nut Covers 5/16 in-18 thread with your 3D printer. Click on the button and save the file on your computer to work, edit or customize your design. You can also find more 3D designs for printers on Hex Nut Covers 5/16 in-18 thread.