I made this for myself. I stopped working on it some time ago, and have no intention to work on it any further. While this being true, I Figured I would upload it so that if you like it, you can have it. (And hopefully be happy about that fact.)
If you like it, and it works for you, then do with it what you will. (I chose the license correctly, but bro, it's yours.)
I have included the blender source file for your convenience. (Minus the scan of my head, because that would have been weird.)
The design calls for 121 coarse threaded Screws (Specs below) but you can use less than that.
[Screw Specs]
Head Dia: 0.210"
Thread OD: 0.110"
Thread Length: ~ 0.466" (maybe should be smaller)
Head Height: 0.080"
It was (somewhat poorly) designed around MY head, thus it might not fit yours.
Because of the way I designed it and with the screws I used, the outside is covered in pointy spikes. (upon impact, Sometimes, they hurt)
The there are two parts that were meant to be printed out of TPU, they are indicated as such.
The author marked this model as their own original creation.