Recently I printed a few of the sanders and they are nice to hold and the screw works as it should. This was my first ever screw print so I was a bit skeptical about that, but for large enough screws, 3D printing appears to work.
However, the design also recommended a squishy pad that goes beneath the sanding paper for better results. Recommended materials are corc, rubber or foam, but I had none of that at hand.
Instead, I decided to test something else. Naturally, with the access to a 3D printer, I wanted to print such a pad. Looking around I found that someone else already made a post about such an endeavor with some traction and an indication of a positive result. I created a box, reduced all perimeters to 0 and set infill to gyroid. The result was the following:
After assembling all the pieces together, I found it worked reasonably well:
Enjoy!