This is an adaptation of 3dverkstan's face shield design so essentially all the credit goes to them. You can check out their page on this topic here: https://3dverkstan.se/protective-visor/ . I was trying to find a way to be able to print more parts at a time since I could only fit 2 on my ender 3 at a time. I had heard about stacking prints before so I figured I'd give it a shot. The only change from the original design is filling in the cavity at the front so that they were no overhangs/supports needed for the parts. Then I simply added a 0.2mm gap between each model. I attached the step file as well if you wanted to play with any of the parameters and customize it in any way.

There's a picture in the files showing how you can print less than 20 using a simple z translate in cura if you so desire. There should also be an attached video showing how you can separate them with flush cutters. I personally use 6 in diagonal cutters from harbor freight ( https://www.harborfreight.com/hand-tools/pliers/6-in-diagonal-cutters-63816.html ) that work better for me but flush cutters can definitely get the job done no problem.

This is for the version using the american style hole punch pattern original file name: "Visor_Frame_NORTH_AMERICA_LETTER_v3.stl"

There's a group of us trying to get as many of these made as we can and this has helped our production speed a ton, hope you find it useful as well!