Mounting a transducer

[todonnell]

Hi all,

I want to replace a depth sounder which is through-hull. I suspect I may not be able to find something that will fit exactly in the place of the old one, so I am considering other options too

One is to buy a fish finder, they all seem to be transom mounted, this will not work for me, but it was suggested I could epoxy it in place low down in the box of the boat (where it will be below the waterline) As long as there are no air-bubbles, I was told, this should work fine. Does anyone have any experience of doing this sort of thing, and any advice?

Thanks
Tim

 

[todonnell]

type in last post

"Box" should have been "bow".....

 

[simonfraser]

Re: type in last post

yes, that will work must be under water, no air bubbles, stick it down with a dab of silicone, or epoxy it in place.

your hull must be solid grp, an air core, wood, steel doesn't work

 

[philmayfield]

Re: type in last post

Yes, I've fixed a transom-mount fishfinder transducer inside a hull with no problems. Stick it in place with chewing gum first to find a spot where it works. You can then fix it with epoxy. Use the slow drying variety to eliminate air bubbles and leave overnight to cure.

Phil

 

[AndersGu]

Transducer

Ditto.. Tried out a suitable spot with modelling putty first. I have an old, cheap NASA sounder.

 

[jimi]

Re: type in last post

Will that give a forward looking view of the seabed as well as a straight down one?

 

[Channel Ribs]

Hi Tim,

Many of the fishfinders can be supplied with in-hull or through-hull transducers. If you would like to PM me more details I would be happy to see if you can get a same spec one as your old/exisiting fitting.

Fixing the compact transom mount transducers inside your GRP hull works well and makes future repairs and upgrades easier too.

Martin

 

[todonnell]

Thanks all - having some problems though

I jumped the gun slightly before reading all the responses here, the guy at the chandlery convinced me that I would be able to mount the transducer to the Garmin 160C fish finder I bought using a compond called "Sikaflex" (I think)

So I tested out the transducer, it worked when just dangled in the water, and it worked when I put it inside the bow and flooded the compartment with water.

But after I tried to fix it in place with this Sikaflex, i momentarily got a positive reading, but then it just flashed the same reading over and over, no signal.

I can hardly believe you might be able to stick it in place using gum! I really had to have the whole device underwater in the bow to get a reading at all

Maybe next I will try another technique I read about, building a well and filling it with warm (runny) vaseline which ought to set without airgaps - a semi-permanent solution

 

[Danny]

Re: Thanks all - having some problems though

[ QUOTE ]

I can hardly believe you might be able to stick it in place using gum!

[/ QUOTE ]It certainly works for a simple depth sounder transducer. I think I used Bluetac, or possibly plasticene, as a temporary fixing before fitting my transducer. I'm sure either would work OK. It's just to provide a temporary, continuous, void-free, interface between the tranny and the hull.

 

[Guest]

Re: Thanks all - having some problems though

Problem with Sikaflex - easy to get air-bubbles in it between face and hull. Maybe you had a greasy smear on the face ?

Have you tried Bluetack ? It does work.

For maintenance and regular cleaning etc. - best is still IMHO the Castor Oil tube .....

 

[stephenmartin]

I did something very similar with my transome mounted transducer for a 160blue fish finder...or was it a 180blue...

The boat was due out for a paint job so i removed the old rotary spinning led device transducer...from a hole in the hull...mounted the new transducer and held in place while the fast setting epoxy went off...then shaped the epoxy to as near a tear shape as i could and eventually tried it it....works a dream

Although not through hull it is permanently in the water (no doubt gathering slime as we speak) painted the tear shape with antifoul and left the transducer surface clear....easy peasy

 

[BrianCullinan]

I had a cheap Garmin 80 which I'd bought before I knew what I was doing and really wanted to use it. It had a transom mount transducer and I followed the advice on this forum to fit it. Actually I first temporarily bedded it in an area of mud from the stern glands down near the keel and this worked perfectly, After a while I simply cleaned that area and made a bed of RTV (the clear kitchen stuff) and settled the transducer into it. Been working perfectly ever since. Be careful though - any hint of air between the hull and the transducer and you get nothing. Good luck