- PROBLEM - Enclosure needs waterproofing.
Parts: Fiberglass enclosure, solid neoprene rubber gasket, silicone sealant, foam tape
I’m designing towards an IP54 rating. Of course, I hope to not have to test this, but it’s inevitable.
- SOLUTION - Stack solid rubber, firm foam tape, and butyl tape to allow adequate height for the battery pack and conform to the curvature of the deck. Add silicone sealant to seal around holes. Make sure enclosure mounting holes are SURROUNDED by waterproofing barrier. Route wires through the waterproof barrier, seal around wires.
Enclosure layering stack-up (from the ground up):
- Fiberglass enclosure
- 3/4" wide x 5/16" thick - closed cell foam neoprene tape, to soak up height differences
- Butyl tape (used wayyy too much) to seal
- Solid rubber neoprene riser, 1/4" thick
I started with a solid sheet of rubber in order to have an uncut, continuous ring gasket (and it was the same price as strips).
Cut the outside with an exacto blade
Marked out the component spacing and cut the inside
Test fit - looks good, too bad I need more height for the 21700 cells against the curved deck
Tried 1/2" thick neoprene foam tape. Too thick.
Laid down one full layer of butyl tape around the entire length of the base gasket. This is too much butyl tape.
Butyl tape is impervious to pain, to curses, to your futile cries of anguish. Also, you cannot drill through butyl tape - it gets everywhere.
After ordering probably 4 different rolls of neoprene foam tape, I finally settled on 5/16" thick as the perfect height needed.
How to get wires through the wall of the enclosure?
There’s a few ways to do this. Traditional options include:
- Drill holes in the enclosure, mount connectors, and epoxy/screw in place
- Drill holes in the enclosure, mount cable pass-through
- Cut a large hole on one edge of the enclosure, feed wires under, forget about waterproofing
- Route a wire channel into the deck itself. Seal wires to deck.
I went a different route for a few reasons. Mainly, I didn’t have enough room for large, bulky, waterproof connectors between the enclosure and the motors/trucks. At 7 plies of canadian maple, I also didn’t trust the deck to begin removing material to route some channels. Lastly, waterproofing is a must. Dead electronics kill the fun.
I decided the create a single piece, multi-cable pass through, and seal it to the deck, and around it on all sides. The cables themselves have the smallest cross-section, vs large connectors, and require the smallest holes. One potential weakness to this approach is that it’s possible to get water traveling inside the wire jacketing via capillary action, if the ends are exposed to the elements.
Initial attempt to drill nice holes directly in the solid rubber gasket with a 3D printed drill guide. Spoiler: you can’t drill rubber with a normal bit. This did not work.
Redesigned, single piece, cable pass-through. Cut a space in the rubber gasket for this to fit.
Test fit. It’s wider than the gasket on purpose, and just slightly shorter in height.
Permanent installation:
I sealed the outside with black silicone sealant, to blend in with the deck, enclosure, and wiring.
I sealed the inside with clear silicone sealant, to allow for easier inspection to ensure no leaks/gaps.
. It would be a lot better it it had a percentage or directly the voltage. I also get some sagging so if you’re accelerating the measurement isnt even remotely precise
