what adhesive should I use ?

[Kim473]

Gluing plastic to transom on an aluminum boat to mount transducer. Not using any bolts at all. What adhesive should I use ?

[Sea Hawk]

I checked the jb weld website and they recommend "waterweld" for metal and plastic so that might work.

[SamSteele]

I used “Marine Goop” on a boat a number of years ago. Routered some keyhole type grooves in the backside so the adhesive would have somewhere to grab. It stayed on fine for the 3 years I had that boat.

I believe 3M makes some Marine silicone/adhesive (5200?) that would be even better if you can find it.

[Ken07AOVette]

Canadian tire sells 5200 which is permanent and 4200 which is semi permanent

https://www.masterbond.com/applications/adhesives-bonding-plastic-metal

[LutherDLG]

I use 3M 5200 for all this kind of stuff - mounting my transducer board, sealing livewell pump thru-hull connections, etc. It's definitely permanent, so try not to get it on yourself or your clothes.

With the transducer board, I still used screws through the transom for adding stability but I filled the screw holes with 5200 before final install.

Canadian Tire has all the variations of it - be sure that you pick one that's designed for "below waterline" use. They all specify whether or not they are.

[TROLLER]

Go over to Cabella they sell the plastic all set up to put on with a 2 part epoxy. Used it on several boats and works great. No holes no mess

[nick0danger]

Tried a number of thing when my plastic transducer mount broke, current JB weld steel stick has worked the best. Marine Epoxy and regular expoxy both broke after a few trips, although the regular epoxy worked better than marine expoxy.

Another thing to note after I mounted my transducer i got a lot of spray back into the boat from it, so do not mount it to far below the bottom of the boat. This is on my 12 foot tinner.

[Kim473]

I used Marine JB weld on it. Will know after a few trips if it holds up. Thanks people.

[barbless]

5200 for sure. Used on mine so far 10 yrs. Just make sure if you have any rivets you notch out the plastic where they come in contact with so you get a nice flat surface and contact

[nimrod]

http://thistothat.com, tells you what you should use for glue

[pikergolf]

Buy the glue you choose and put a dab on the plastic, let it cure, and see if it really adheres. Those slippery plastics are really hard to find an adhesive for. I tried three different glues and non of them stuck, so I used screws through the transom with marine goop on the screws to seal the holes.

I saw on youtube where a guy used a keyhole router bite on the plastic and the used expoxy to get a mechanical seal, but it seemed like a lot of work, and it would be something that would be almost permanent and hard to remove.

[Savage Bacon]

If you have kids you'll know this trick. Just mix a bit of milk with some cereal. Let it dry. There you go. Homemade glue.

[fish99]

construction adhesive pl 5000? is what I have used no issues with it coming off to glue a puck board type material to the crestliner for a transducer mount and no screws