This is an actual replacement clamp for the Reeder Products 2" x 72" grinder attachment. I have included the STL for clamp which requires two 4mm threaded heat-set inserts and one 5mm threaded heat-set insert.
The benefit of this setup is no scratches on finished blades without having to cover them in tape.
The other 2 files are the replacement rod and collar (also require a 4mm insert). I have not printed or tried them yet but I am using the clamp on the original rod. The original rod has an end diameter of 9.5mm. If you have a different setup and have the same dimensions this could work for you. If not, you could print a new rod and collar as well.
I recommend printing with 4 walls and 100% infill and use PETG. It took 32 minutes on my Ender 3 KE.