On 17-May-17 6:55 PM, Jim Wilkins wrote:
"Aussie" wrote in message
...
On 17-May-17 8:35 AM, wrote:
On Tuesday, May 16, 2017 at 3:46:47 AM UTC-4, Aussie wrote:
I'm playing around potting some electronics for immersion in water
up to
10 metres.


Any suggestions?


A good many years ago I was involved in something similar. Instead
of dealing with water it was dealing with high voltages and vacuum.
The first try was epoxy potting. It cracked in temperature
cycling.

So somewhat flexible polyurethane potting was tried. It did not
adhere well enough.

The solution was a metal box with a gasketed lid. It was great for
reworking as in did not have any conformal coating to remove. The
connectors did have to be a special design. They were kind of
like morse tapers. Necessary because the voltage was about 2000
volts. Surprise , surprise the connector was designed on paper and
worked without having to be revised.

Dan



A water proof enclosure would be nice but the price is waaay to
high!

Perhaps you could research high-performance professional and low-cost
educational solutions:
http://www.hydrogroupplc.com/pressur...netrators.html
http://oceanexplorer.noaa.gov/explor..._gr9-12_l4.pdf

I got a good deal on a vacuum oven that leaked through the wiring
feedthru. I replaced it with a solid plug and haven't found how to
make one. Here's one possibility for solid wires or sealed tubes:
http://www.omega.com/pptst/MFT.html

Light bulbs have wire leads that seal vacuum-tight in glass.
https://en.wikipedia.org/wiki/Fernico

-jsw




Thanks, I'll do some reading.