I could not leave well enough alone. I wanted a set of PVC pipe fittings that I could use as a shelf. While the previous version of my enclosure brackets worked, I wanted to see if I could trim the print time and make something that looked less blocky.
You can use fluted plastic, foam core board, or plywood for the shelf. There is a 4mm hole in each bracket so you can use a M3 cap screw to secure it to the corners. If you need to, you can print the door brackets from https://www.thingiverse.com/thing:3591032 to help stabilize the shelf. All the brackets are designed to hold the shelf flush with the bottom of the PVC pipe, to give you a lip around the shelf.
You can see a video of this at work here, https://www.youtube.com/watch?v=hAVWsb-O5UQ&list=WL&index=4&t=0s
You'll need 1/2 inch schedule 40 PVC pipe, which you can get at any hardware store. If the fittings are too loose, use tape to shim them into a snug fit.
I use this shelf for trade show displays, and you can change the colors to help them pop.
There is a half-circle tab on the edge of the brackets to help prevent warping, you'll need to trim that off.
I printed these in PETG, but PLA or other materials will work.
Trim off the crescent tabs after printing.