The case was designed a while ago to hold a few modules for testing without taking up too much room on a crowded bench or desk.
It’s around 54hp wide, and 65mm deep.
The rails are built in and laser cut to accommodate M3 bolts. They’re cut slightly smaller so the bolt cuts threads in the wood and holds the panel tightly. Hardboard isn’t the most durable material so you’re not going to want to rearrange the panels too often.
It was designed in Adobe Illustrator, and converted to DXF and SVG. DXF works best for lasercutting (and least on the laser I use).
Get the plans here: https://github.com/THX2112/Laser-Cut-Eurorack-Case