I know there are some of these out there, but none suited my application, so here is my version of a housing for the common 2 channel relay boards (Sainsmart/Sunfounder).
The board is mounted with 4x M3 screws, 2 of which need to have a rather small head, due to the spacing of the connectors on the PCB (you can see what i mean in the picture). The top just snaps on.
Attention!
The type of board used here is usually rather cheap and due to this the dimensions and positions of through holes may vary.
Thanks to Richard Hornung for the relay board model:
https://grabcad.com/library/sainsmart-2-channel-relay-module-1
2chrelaycase_bot.stl | 1001.4KB | |
2chrelaycase_top.stl | 217.9KB |