Is Epoxy better than Goop for transducer mount?

[dgax65]

[quote=bluesquids;21527]

Originally Posted by aguachico

Marine goop has UV inhibitors.

quote]
Is UV inhibitor a bad thing?
I thought 5200 was standard for thru hull applications.
It seems very flexible. Have not tried 4200 yet because it says
it's less adherent than 5200.
Heard that the kaya tank installs are using Goop now.
I think prep is most important anyway you decide to go.

I'll agree with that. I've used 3M 5200 (regular and quick cure), Marine Goop and Sikaflex. While I have had mixed results with the sonar performance, all have adhered well to the hull. The key is to rough up the hull first. I really had to struggle to get a couple of the transducers off.

Marine Goop works well but you have to take precautions to prevent bubbles from forming under the transducer. Have everything ready to go before you apply the Goop. Level the hull so the transducer won't move. The key is to put the transducer down in one smooth motion. You don't want to disturb it once it is in place. Every movement seems to create more bubbles.

I've found that a thin layer works best. I just put down enough Goop to seat the entire transducer surface. After it cures for a while I go back and put a little more Goop down. When I apply the second layer I put Goop on the top edge of the transducer and let it run down the sides to contact the first layer. I think this holds the transducer in place better. Some people rough the surface of the transducer for better adhesion. I would rather cover the top than rough the transducer face.