3D-printed case for a 5-panel LED matrix banner

I wanted a scrolling LED sign, so I lined up five Waveshare 64×32 RGB panels into one long banner, 320 pixels wide and a little over four feet long. Loose panels and a pile of wiring don't hang on a wall very well, so I designed a case that holds all of it: the panels, the power supply, and the Raspberry Pi that runs it.

One module per panel

The first version was 19 separate parts: rails, back plates and end caps. I redesigned it so each panel gets one printed module, with the top and bottom walls, the front lip, the panel ledge and the back all in a single piece. That took it from 19 parts down to 5, and from 40 screws down to 16. Every module is about 270 mm long, so each one fits on the printer bed with room to spare.

How the panels go in

No screws touch the panels. The top and bottom walls of each module have a thin lip at the front and a ledge behind it, and the 14 mm thick panel slides in sideways between them. The lip only covers about a millimeter of the panel's edge, outside the LEDs, so nothing blocks the display. Once the modules are joined, the panels next to each other box each other in, and the end walls close off the two outside ones.

Joining the modules

Each module has two tongues sticking out of one end, top and bottom. They slide into the next module and get two M3 screws each, into heat-set inserts I melted into the tongues. Four joints, 16 screws, and the whole thing is one rigid banner.

What's inside

Facing the sign, the left end holds a 5 V 30 A power supply. Five panels can pull around 20 A at full white, so it needs the headroom. The supply sits on ribs a few millimeters off the back with vents beside it, strapped down with zip ties, and the mains cord comes in through a cable gland in the end wall. The right end has standoffs for the Raspberry Pi and RGB matrix HAT. The HUB75 ribbon runs from the HAT to the first panel and chains down the line, and every panel gets its own 5 V feed from the supply.

Printing it

All five modules print back-side down with the open front facing up, so nothing needs supports. The ledge has a 45° underside so it bridges cleanly. There's also a small fit-test piece of the slot, about a 10-minute print, to check that a panel slides in snug before committing to the big prints. Each module runs about 8 to 12 hours. Since a mains power supply lives inside, at least the power end should be PETG or ASA, not PLA.

Hanging it

Every module has two keyholes on the back, so I can use whichever ones line up with studs or anchors. Screw heads go through the round part of the keyhole and the banner slides down onto them.

The images here are 3D renders from the print files, and the message on the panels is a mock-up. The build is still in progress. Photos of the real thing on the wall and lit up are coming.