Starting Foil Drive like DIY - in Israel

Annoying is funny word for this situation…but it wasnt as bad…

Sorry for your loss! But I still think valuable to share the experience since I don’t think many have tried this design.
In the video you fell in and the box is attached to you and fully submerged. I think it highlights how it is subjected to more challenging conditions than the typical assist box attached to a board.

Was it a little warming? :crazy_face:

Actually it wasn’t at all, except the smoke. I felt nothing. I use kite harness which is pretty thick and I guess that is why I didn’t feel anything

I tend to agree with you, I think that heat raises the air pressure in the box and when I am falling to the water it cools very fast and air pressure is reduced rapidly and sucks water in.
I am pretty sure that water did the damage, as it is clear that there is hot spot and only 4 battery cells dies the rest are OK with decent charge that fits the 20 min that I was in the water. 3.8/3.9V
I think that what might have caused it, is spaghetti of wires I had (I had the BEC burned in one of the previous trials and replacing it I didn’t wrap the wires back together) and maybe one of the wires was caught between the box and the lid and allowed the box to suck in water.

My plan

  1. get pelican 1170 box which has a valve
  2. add another battery row to reduce current on each row basically move from 10s2p to 3p

Well the valve on the Pelican 1170, if it’s a pressure equalization valve it can open for a pressure difference in either direction. That might be another point of failure allowing water back in?

The pelican ones are a gortex valve. They let vapour pass though, but not liquid water.

With my DIY boogie I removed the goretex valve and used a bolt and an oring. Never had leaks, from the valve, but I wanted to reduce the vacuum effect when rapidly cooling.

Fun fact. Goretex is expanded poly tetra fluoro ethylene. Teflon on your frying pan is the same stuff, just not expanded.