How to waterproof your electronics

[TriplePointDesign]

This blog post is a summary of the many waterproofing methods we've used over the years in our open source logger project including the DIY underwater housings we make from PVC plumbing. Also describes how to oil-mount pressure sensors to protect them from salt water corrosion:

https://thecavepearlproject.org/2023/03/17/waterproofing-your-electronics-project/

[aeberbach]

Thanks! I am hoping to get a network of soil moisture sensors in this year, it will be very useful to read this.

[TriplePointDesign]

We did a big student project last year with soil sensors that I should get around to posting about. Fair word of warning: getting soil data that is 'qualitatively understandable' when you glance a the graph is really quite easy. Getting soil moisture data that is quantitative is really darned hard. Relative to something like light sensors, calibration is more difficult because soil environments are so incredibly diverse.

[TriplePointDesign]

After waterproofing, you need some way to test if it really worked right? We needed a way to test our little falcon tube loggers and household water filter housings are a good solution as the domestic water pressure range of 40-80psi overlaps nicely with sport diving depths. The internal clearance of that 4x10 filter housing is only slightly larger than 4.5" x 9.5" but could accommodate a good range of other dive computers, lights, etc for testing.

https://thecavepearlproject.org/2023/05/24/a-diy-pressure-chamber-to-test-housings/

[barshatriplee]

In this article, I can see a picture of a capacitive soil moisture sensor. I can see that it has been waterproofed by hot glue. But from the picture, it seemed to me that hot glue has covered not only the circuit but the electrode also. If the electrode is covered, how will it take reading from the soil? Isn't it supposed to touch the soil? Or there is no glue over the electrode?

[f4eru]

Capacitance sensors are insulated by principle.