You’re probably here because you asked me how I made the crystal lattice modal thing.
If you’ve only seen the Short you might want to watch the longer video here as you can see the details more clearly.
It’s three sheets of laser cut acrylic: two outer sheets, and a spacer sheet in between.
The resulting cavity is filled with about 3000 2mm ball bearings. The middle sheet of acrylic is also 2mm thick. That fit is too tight, so I added a few paper squares to each corner to make the cavity slightly thicker. You might be able to find a combination of ball size and acrylic thickness that doesn’t require padding with little paper squares!
I used 5mm acrylic for the front and back but that was too thin as the whole think flexes way more than I would like. I don’t know the best thickness but I would guess that 10mm would be fine.
The whole thing is held together with nuts and bolts in the corners. But you could use acrylic weld.
Here are the files I sent to the laser cutter: