Fish Finder Shooting Through Ply

hairymick · Post by **hairymick** » Wed Sep 20, 2006 3:34 am

Hi guys,

I bought a Garmin 140ff the other day and installed it in my beautiful Wadefish.

First transducer install was in a piece of poly pipe that was siliconed to the bottom and transducer was mounted in it. The pipe was filled with water. It worked, but the readings were not strong and the picture on the screen was intermittent.

Next, I smeared silicone to the bottom of the yak and stuck the transducer down on it. There were no air bubbles and the installation was rock solid. This was even worse. The sounder would not read in depths under about 15 feet and often would not read at all.

I thought my power source may have been a little weak so I bought a new 12volt dry cell and charger - no change.

Today in desperation, I took the transducer off the bottom, cleaned it up and drifted about just holding it beside me in the water. Perfect, clear and strong signal. It would seem the unit is working perfectly but it has problems shooting through my ply?

I'm looking for suggestions guys, please help.

Kayak Jack · Post by **Kayak Jack** » Wed Sep 20, 2006 9:19 am

Mick,

While I knew a signal through plywood would be subdued, I wouldn't expect the drastic reduction you experienced. (That's Yankee-speak for "Beats the $hit outa me, Sarge!")

I'd used a locator bolted to a rod clamped to a canoe gunnel & it worked good. I've held it tightly against the bottom of the boat and had a modicum of success. I've read articles where people siliconed it to the boat as you did, and they seemed to get good readings.

Since I don't like cutting holes in the top of a boat, I surely wouldn't recommend to anyone that they cut a hole in the bottom for this or any other purpose. Now, Mick, I'm flummoxed.

What is the thickness of your plywood?

surfman · Post by **surfman** » Wed Sep 20, 2006 4:24 pm

I was wondering if that is what you did. I asked about that in the builders log section. I have installed transducers on the inside bottom of fiberglass boat hulls and they worked great but, I would think that the fiberglass is fairly solid. Plywood is not really solid. It is porous. I wouldn't think it would work very well. What you could do is make a fiberglass plate and cut out a section of wood and install the plate into the bottom of the boat then mount the transducer on top of that. But that sounds like a lot of trouble. A transom is a handy place for things like a transducer.

hairymick · Post by **hairymick** » Thu Sep 21, 2006 1:27 am

Hi Jack & Surfman,

Thanks for the replies.

What I have done is to sand out roughly the size of my transducer with my beautiful little Dremel. I have removed all the inside glass and ply leaving only the glass on the bottom intact. then I have done like a flat end pour of epoxy & wood-flour into the recess.

I will attempt to shoot through that and let y'all know how I get on. I have shot through the bottoms of fibreglass and aluminium boats before without a problem.

My cheap 3mm ply has only a thin veneer on each side with some sort of white chalky lookng stuff in the middle. It seems pretty porous so I reckon that wouldn't be helping.

surfman · Post by **surfman** » Thu Sep 21, 2006 7:11 am

Yes I bet that will do the trick. I have even used a piece of plexi glass sanded into a wedge to make a V bottom level and that worked good too. Anything would be better than attaching it to the outside. Keep us posted.

Kayak Jack · Post by **Kayak Jack** » Thu Sep 21, 2006 12:28 pm

My personal preference is for the Xducer to be mounted forward rather than aft. Thinking is, I'd rather know what is coming up than what I have already run over.

hairymick · Post by **hairymick** » Thu Sep 21, 2006 3:21 pm

My personal preference is for the Xducer to be mounted forward rather than aft. Thinking is, I'd rather know what is coming up than what I have already run over.

Hi Jack, Toomuch turbulane at the bow

Kayak Jack · Post by **Kayak Jack** » Thu Sep 21, 2006 3:30 pm

Too much turbulence?? I don't understand. If that part of the bow is underwater, it makes no difference. Are you saying that part is out of the water too much? Too much air in the water?

" 'Splain yoself, Lucy" (Ricky Ricardo)

hairymick · Post by **hairymick** » Thu Sep 21, 2006 3:40 pm

Tis a planing hull, not that it planes all the time, but is frequently in out over and under the shops here.

Feedback from Aussie kayak fishing forum is that the sounders won't work properly when mounted in the bow when used off shore. my experiences the other day would seem to confirm this.

fery intermittent readings that seemed to co-incide with patched of rough and smoothe.

Oldsparkey · Post by **Oldsparkey** » Thu Sep 21, 2006 3:50 pm

Jack....

It is simple ..... Some folks do paddle faster then 1 & 1/2 MPH when they are in there boats. Yes.. I know this is not the Geezer way but some folks do it anyway.

Heck even some of the folks don't tote there boat over dry ground, they just paddle around it like any normal thinking person would do.

Darn .. They even catch fish, clean them and cook them up for there supper, or any meal. Fish does come from the lakes and water, not all of it is packed in tin foil or cans, there is something called ........FRESH FISH. Now chasing them a paddler has to be quick and stealthy or that wily fish will avoid them and this is not a good thing. It means they will only have the beans for supper and no fish to go with them.

Ya have to be quick or just eat beans.

Besides the air bubbles under the hull really do goof up the fish finders information.

Chuck.