Goal of this project was to create a case for WisMesh base board from RAK wireless:

https://store.rakwireless.com/products/wismesh-baseboard-rak19026

I wanted the case to be waterproof and have a decent battery life. It is something I can keep semi-fixed at home, when it is not mobile in the car with me or hanging from a tree relaying Meshtastic packets.

WisMesh base board has GPS and accelerometer built in and I needed to accommodate the GPS antenna in a waterproof manner without deafening it.

Also I chose the “oled mounted” variant. Display was tertiary priority to be honest (in my case, you can implement the window differently, mine is Falloutish on purpose).

Waterproofiness is accomplished with several things. The case itself is PETG with 4 perimeters and 25% infill. The main gasket (pictured) is think layer of foam TPU which has been tested to work well as gasket (in room temperatures). The connectors are all waterproof: USB pass through, N-connector for antenna, vent plug to allow humid air leave the case. The base board also has user-button and on/off switch. For them I created holes in the case to allow operating them and designed a printable gasket that is left on when in outdoor use (you can see it in the pictures). It is a black layer of rubbery material that is tightly fit to the holes, keeping it waterproof up to IP-somethingsomething (not certified).

The antenna connector was the shortest I found without having to build it myself with 5cm cable. The installation requires patience and smallish fingers/tools. For GPS antenna there is a designed location on top of the case. Performance has been good so far. BT antenna goes to the wall, vent plug screws in (remember the O-rings) and the base board is screwed in with M2 screws / bolts directly to the plastic: Sorry about that, I just could not get the heat inserts in nicely.

Case is attached with 8 M3 screws (heat inserts). There is a separate battery holder inside the case which allows 8 heat inserts to attach 18650/21700 battery holders. I installed 2 * 21700 on the other side and managed to fit 1 * 21700 on the radio side with total capacity of ~15Ah. Should last some time with nrf52 based radio.

The battery holder attaches with 2 * M3 screws (14-16mm), but they are honestly optional. The battery holder stays but just fine on its own. I had the EU variant of the base board and connected 10kohm NTC termistor to the battery connector to allow charging. It goes between battery minus and the termistor connector (this is only the EU variant, for you US/ROW don't worry, just do what you always do).

For the window (which was low priority for me. It just had to be waterproof) I attached piece of glass inside the case, then epoxied from the outside. Epoxy was left with some air bubbles in it, giving the radio a Falloutish look - which is why I called the node “Pip-Boy” (tm, not mine). You might want to use piece of acryl instead, maybe seal with transparent silicone from outside (edges).

Do I recommend this case? Not really. Was it fun to design? Yes it was. Also I am happy with the result. Will test more going forward.

Specs/BOM:

• RAK WisMesh baseboard with accelerometer, mounted OLED, GPS.
• Alfa AOA-868 outdoor LoRa antenna
• M16x1.5-10 vent plug (IP68)
• U.FL to N-connector 5cm
• 30cm waterproof USB-C pass through connector
• 3 * XTAR 21700 4900mAh
• 1 * 21700 holder 1x
• 1 * 21700 holder 2x (parallel)
• M6 heat insert on the cover to allow screwing in neodymium magnet (for holding on cars, fences, etc.)