Great design! I really appreciate the thought you gave to strength... putting the force along the layers and not the weak point between layers. This feel very solid.
Only print problem I had was the screw was too big.. it would only turn one rotation. I re-printed it with X/Y at 96% and it worked fine. The "box" is also a little tight in the frame, but that's probably by design. I guess I could have printed the frame a bit bigger, but it was quicker to print a new screw.
As you can see, I made my first puck. I really wanted to try it, so I grated half of an active bar! :) It worked really well.
I realize you're probably done with the design, but one suggestion I have is a deeper lid and longer guides on the base plate. You really need to fill the box up pretty high to compress a solid puck.. lots of room for under-fill errors. With the current design, I probably need to go through 4-5 bars before I have enough slivers to pack them.
Thanks a lot and great job!