Re: Epoxy for transducer mounting

Steven W. Barnes (oldsurfdude@worldnet.att.net)
Thu, 26 Nov 1998 16:43:11 -0800


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West Wight Potter Website at URL
http://www.lesbois.com/wwpotter/
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J.J. Falkanger wrote:
>
> Hi folks,
>
> I put a Humminbird fish finder in my boat back in August, and love
> it. Today I fired it up, and noticed it was reading as if I was
> grounded. When I looked in the hull to where I had slow-cure epoxied
> (from Ace Hardware) the transducer, it sure enough had come loose (the
> epoxy seems to not have bonded to the bottom of the transducer).
>
> I'm looking for some help on a couple things. I know several folks
> have epoxied the transducer inside the boat, what type of epoxy did
> you use? Is it still holding?
>
> I set the transducer back in the 90+ degree heat of August. Although
> it's in the 60's now, we've been a bit colder, and I know stuff
> shrinks in the cold a bit. Might it be better to epoxy it now while
> it's cool, or shouldn't that make a difference?

It sounds like you used polyester resin which has something like a 10%
shrinkage range over normal temperatures. It is not good for marine
environments because it does come loose after shrinkage and expansion
several times. You should use the more expensive, but much better epoxy
resin, well suited to marine environments and only about 1% shrinkage.
I'm telling you this from memory, so I may be off on the details, but
generally, it goes something like that. Been there, done that!

:)

Steve Barnes sailing a Capri 16, #74,
and saleing a Potter 14, #561, in San Diego.
"Everything is everything!"
OLDSURFDUDE