Transducer placement on 15' Avon

[jondavies]

I'm setting up my 15' Avon SIB and I would appreciate some advice about where to mount a transducer.

I have a portable Humminbird FF, which is convenient because my boat doesn't have 12V and so I run the unit on self-contained rechargable batteries. The suction cup mount was not reliable so I mounted the transducer on an aluminum bracket that clamps to the transom. So far, so good.

Unfortunately, I'm putting Smart Tabs on the boat and this is going to severly limit space for the transducer bracket. The only space left will be about 12" in the center of the transom -- in front of the prop -- which I undertand is a very poor choice.

Are there any other places to put a transducer on a SIB? Would a through-hull transducer work in a boat with an aluminum floor?

Thanks for any answers to this and for all the great advice on other topics I've found here,

Jon

 

[nobrainsd]

Re: Transducer placement on 15' Avon

It definitely gets tight on the transom with tabs and a transducer. The smart tabs, even when fully retracted with the cam/line/cleat set up, do not go up as high as you might think (though higher than the pic shows). My tabs could have been installed a little farther out without risk of hitting the tubes. I left room for my trailering strap as is shown in the picture. I have an aluminum transducer mount. The bottom part is thin and can be extended to just below the transom edge or deeper. The transducer (A) works fine at the edge setting with slow speeds. I have better luck while moving with the transducer extended fully, but it likes to catch kelp so I don't cruise with it down all of the time. Yes, the location near the prop and, in my case, speed tubes does not help the fish finder at all. I had the transducer mounted at a position farther out before I installed my trim tabs. I don't think the fish finder worked any better then at any speed. Inflatables just make too much disturbed water flow and suck air into the mix. I have not had luck with a combo of fishfinder and boat speed at all. Works just fine when I slow down. Both the Tabs and transducer mount retract so the trailer bunk doesn't hit them. The Smart Tabs were definitely worth wedging in. Think I have enough epoxied over holes in my transom? Dang, That looks terrible.

The thru hull transducers do not like air gaps. Gluing to my fabric bottom was not an option.

 

[jondavies]

Re: Transducer placement on 15' Avon

Thanks for the advice.

The Smart Tabs should be delivered shortly and then I'll have a better idea of the options for the placement of the transducer.

I'm not too bothered about inaccuracy at speed -- the boat will mainly be used for diving and I'll primarily use the finder for lining up on bottom structure and checking depth prior to anchoring.

I'll let you know how it works out when I get it in the water.

Cheers,

Jon

 

[Dry Diver]

Re: Transducer placement on 15' Avon

I am in the process of doing the same thing to my boat. I would love to see what you end up doing once you are done with it.

 

[Huron Angler]

Re: Transducer placement on 15' Avon

My understanding is that thru-hull transducers will only work in fiberglass hulls...with no air pocket/void as mentioned.

If not I'd love to mount a thru-hull rather than drill holes below the waterline on my tin cans

I have a portable Humminbird finder and have lost the suction cup attachment as well

 

[jondavies]

Re: Transducer placement on 15' Avon

<<I have a portable Humminbird finder and have lost the suction cup attachment as well>>

HB sells replacement suction cups for about $10. It worked fine on my kayak (smooth surface, slow speeds) but it wouldn't stick to Hypalon.

FWIW, this is the transducer bracket I found at BPS and it was perfect, except for the fact that there's no room with the Smart Tabs:

http://www.basspro.com/webapp/wcs/stores/servlet/Product_10151_-1_10001_387____SearchResults

I'll report back when I find a solution.

 

[Huron Angler]

Re: Transducer placement on 15' Avon

Thanks for the link, didn't know they make those I like the design, simple and not a lot of moving parts.

I have a larger boat that I will be mounting a transducer on permanently, but these brackets would be great for my 12' aluminum rig. I ended up fabricating something very similar to that myself after losing the suction cup.

Cheers

 

[miker-gr]

Re: Transducer placement on 15' Avon

i had see once on boat a very nice system for portbable fishfinters.
The guy probably because he didn't want to attach permanently the transducer on the hull, he attach the transducer on a stick and witha special adapter fit on the transom he could fix the stick on the transom!