I plan to customize a closed enclosure for my desktop-level 3D scanner/turntable, so I don't have to turn off the lights every time I scan.

I got a few pieces of 3mm-thick plexiglass panels, with a black vinyl film on the surface. One of them is 400mm×300mm, and the other is 300mm×300mm. While holding these panels, I suddenly had an idea: Why not print some corner blocks and straight rails, and then assemble the panels together to create a fully black protective cover for my scanner/turntable? The key point is that we must strictly prevent light from leaking into the box, so the joints between the components must be seamless and tightly fitted, without