I bought a few Core Modules as part of the early bird campaign this spring, and wanted to use one of them as a gateway dongle. So I whipped up a small enclosure for it, using OpenSCAD. The design files are in a Github repository and I also created a library with design features that I intend to re-use across designs. You will need to install the library in order to compile the designs from the core module enclosure repository.
This goes together without fasteners. The core module is held in place on standoffs from the bottom part.
Here it is with a core module mounted. It fits very snugly and wont go anywhere.
Snapped together with the buttons in place. I designed the buttons to lay flat against the case, because they should only be used during firmware upgrade and radio pairing.
I tried to make it compatible with both the older low-profile core module and the newer model with a 0.5 mm thicker PCB by designing two sets of snaps, 0.5 mm apart, on the bottom part. I don’t have a thicker core module so I simulated the extra thickness using some washers.
Front view of the enclosure snapped together with washers in between. It doesn’t hold together as strongly as with a thinner core module, but it doesn’t come apart by itself either.
Overall I’m very happy with this design, and somewhat surprised that it worked on the first attempt. The cutout for the USB connector could be slightly bigger to more easily allow a core module to be inserted and removed. As it is, I’m not sure I can remove the core module without damaging either the USB connector or the case.
The snaps could be simplified in the model. As prism shapes they are too fine to be reliably printed using FDM, even at 100µm layer height (as the above print).