Hull sensor adhesive / glue recommendation

[nfluester]

i am planning on drilling a hole in the bottom of my boat (i'm a little scared!) to fit a sonar sensor.

obviously i want to make sure if doesnt leak does anyone have any recommendations for sealant / glue / adhesive

should i use Sikaflex or will good old CT1 be ok?

any other tips or help would be appreciated

 

[CliveF]

does it have to be fitted through hull? I have seen them fitted into liquid filled tubes bonded to the hull and they fire through with perfectly good results.

I know mine is only a kayak but I bonded the transducer direct to the hull with sikaflex 291i. I made up a small open top trough with sticky foam.
Squeezed the gooo in with NO nozzle so that I could get a bubble free blob in the trough. I then pushed / rolled the transducer into the goo to ensure there was no air trapped between the two. Held down with weights until set. I get perfectly clear soundings. however that is only through 8mm of polypropylene.

If you have to go through more than 25mm of fibre glass then I guess it is back to a hole unless some one tells you different.

regards Clive

 

[Rappey]

I would personally go with sikaflex as it has been used for this very thing for so many years and dont think ive heard of anyones fitting leaking.
Using something else would be a bit unknown in the long term ?

 

[omega2]

What hull? what boat? what sonar?, a tip or two, set up the head, and connect power leads place the transducer over the side-of the boat and note the return echo for quality, that is going to be the bench mark. Now place the tran into a plastic bag and add water, then starting about 2/3rds back from bow try different places on the inside of the boat below water line and note the return echo, find the best place for convenience and signal strength. when you are happy mark area and sand down to a smooth surface, then you can either build a well and fill with baby oil or even blue anti anti freeze place the tran into that and the job is done, We just knock up araldite and stuck ours down, making circular movements to exclude any/all air from the contact between hull and trans, If you are unfortunate enough to have one of these sandwich built hulls the you have no option but to mount outside and that means drilling a hole

 

[nfluester]

sorry i should have added more detail the hull is fibreglass 37 foot Sealine and the sender is a plastic raymarine Chirp through hull

 

[Plum]

i am planning on drilling a hole in the bottom of my boat (i'm a little scared!) to fit a sonar sensor.

obviously i want to make sure if doesnt leak does anyone have any recommendations for sealant / glue / adhesive

should i use Sikaflex or will good old CT1 be ok?

any other tips or help would be appreciated

Folow the manufacturer's advice. Some manufacturers say don't use certain types of sealant which contain substances (solvents?) which will weaken the plastic of the through-hull fitting.

www.solocoastalsailing.co.uk

 

[omega2]

sorry i should have added more detail the hull is fibreglass 37 foot Sealine and the sender is a plastic raymarine Chirp through hull

Try what I suggested! you will soon know if you have a sandwich hull i.e no signal.

 

[QBhoy]

sorry i should have added more detail the hull is fibreglass 37 foot Sealine and the sender is a plastic raymarine Chirp through hull

An almost identical transducer worked on my Sealine (under the engine) inside the hull and sat in a generous blob of silicone. Since then, I haven’t heard of a single time that this didn’t work on a normal planing hull and comparable thickness. Try it in a few places with Vaseline first, to get best results. Make sure it still works at planing speeds too. Best away from the very rear, but rearward enough that it’s not affected by air under the hull on plane.
good luck.