Summary

Trays like these are commonly used for small prototype or productions runs with some manual steps, where there is a need to store the PCBs in between processes. It helps keep track of completed items and helps move them from one workstation to another.

The design is done using OpenSCAD and the size can be customized to have the size you need. Length and width are the outer dimensions of the bottom part, and the upper part will add 3mm on all sides (6mm in total for both length and width). Using this dimension makes it easy to design trays that fit into other containers (eg. the medium and large versions uploaded, that fits a small Auer Packaging EURO crate, specifically the 200x300mm one, so that is sits on the top).

The side is open, to allow slightly wider PCBs to stick out, or if there is a connector that is very close to the edge.

When printing multiple in the same size, they stack nicely and compact for storage.

Ideally this would be printed in ESD filament, but that is really expensive and if you aren't otherwise set up for a full ESD protected workflow, regular PLA or other non exotic filaments will work OK. I have printed mine in matte black PLA.