Transducer

[trumpetguy]

I have re-located my Depth sounder transducer from a transom mount to a through hull mount. Using epoxy I glued a 3" PVC cleanout fitting to the fiberglass under the aft berth on the Port side but close to the centerline. I used 5200 to seal the inside of the fitting and lined the bottom of the circle with a thin layer of 5200. Filled the fitting with water, placed the transducer into the fitting and nothing happened. All dashes on my Eagle digital. The mystery is that if I simply hold the transducer firmly onto the bottom (in the same location) I get a good reading. Could the problem be that the transducer cannot shoot through the 5200? I suppose I will just epoxy the transducer right to the fiberglass since that seems to be an alternative mounting method.

I sure would like to know why it will not shoot through the 5200.

BTW, this was all with full ballast.

[waternwaves]

5200 is physiclly flexible, and acousticly almost worthless.......

now if you had some good silly putty

seriously.......even plumbers putty is better than 5200 or 4200 for an interface, 5200 is just too adsorpent, signal attenuation is greater than 97% for 3/16's of an inch thickness at 200 khz

when playing with sound.........

The stiffer the solid the better. and if you are using glass or epoxy to bed it... DO not use bead fillers. solid glass........only.

[Paul S]

I did the exact same thing...5200 a pvc connector ring to the hull..then put a dot of 5200 on the sending unit to hold it in the ring..filled the ring with water (water lasts a season). Works great!

Paul

[paj637]

I used a toilet wax seal. (NEW ONE of course) Saw that idea on another forum. I broke off a chunk and worked out the air bubbles and set the transducer right in it. It seems to be working fine. I just don't know how it will hold up down south in the heat parked in my driveway. May have to go to plumbers putty.

[kmclemore]

I used a toilet wax seal. (NEW ONE of course) Saw that idea on another forum. I broke off a chunk and worked out the air bubbles and set the transducer right in it. It seems to be working fine. I just down know how it will hold up down south in the heat parked in my driveway. May have to go to plumbers putty.

Hmm.. good idea! I think it will work out fine in the heat - remember that it's stuck to the hull and that's up against relatively cool water, so given the thermal transfer, it will never get all that hot.

[trumpetguy]

Thanks for the replies. I was supicious that the 5200 I used to fully line the bottom of the ring was my problem. I will try to scrape off the 5200, leaving the PVC ring, which I glued with Epoxy. If that doesn't work I will just Epoxy the thing right to the hull.

[Frank C]

I have re-located my Depth sounder transducer from a transom mount to a through hull mount . . .

The transom xducer is a skimmer (hydropod?) rather than a puck.
Are you trying to attach the skimmer to the bilge?

[LOUIS B HOLUB]

My prev. boat, a Mac 26S, and present boat, a Mac 26X, had thru hull readings that worked well with regular Dupont silicone. My transducers were positioned on a thin layer of silicone flat on the floor, with additional generous amounts of silicone surrounding the unit (with care to avoid any bubbles in the silicone).

edit add: Regarding my Mac-X -- Perhaps I shouldve mentioned that I placed the transducer flat on the floor in side the galley area. It has worked well, and hasnt been in the way of storage, etc. Hope this helps someone.

[trumpetguy]

Frank C, This is a puck style that can be either transom or bilge mount. I had it mounted on the transom but the rapid collection of marine life (wet slip year round) affected the performance in a big way...translate would not read most of the time. The mfg. (Eagle) says it can be mounted to shoot through the hull, which it does if it is just sitting on the hull. I am going to try to epoxy the thing as nthe mfg states. I was out today with a plumbers putty mount and it worked only sporadically.

Question: Is there ballast under the aft berth area? I keep my tank full virtually all times so that should not be an issue, but it is worth the asking.

[Paul S]

it works better with the ballast in on our M

[Frank C]

Question: Is there ballast under the aft berth area? I keep my tank full virtually all times so that should not be an issue, but it is worth the asking.

There surely is ballast under a 26X's aft berth, assume that's true for 26M. My boat has two rather large pancake-style ballast tanks, fore and aft, connected by two ballast tunnels, one running along the starboard hull and the other along port. If you open all your bilge hatches and view the tunnels, you'll see where they merge into the main ballast tanks.

You should NOT mount a 'ducer over the ballast tank. Keeping ballast full will never provide a reliable signal thru the two layers of glass and the intermediate ballast, since the tank can never be completely full. The most common choices for mounting a depth 'ducer in a 26X are under the ice chest or under the aft berth right at the companionway ladder, both spots with single layer of glass (pure hull? ). We need to get as close as possible to centerline to keep a reading when heeled. But we must also try to avoid being too close to turbulence from the centerboard trunk ... more art than science.

[Sloop John B]

I mounted my huminbird puck under the ice chest next to the ballast channel. Works fine when I have ballast in but skips all over the place (3feet..365 feet...ect.) when I don't have ballast in. I plan to move it back behind the head, that is, off to the starboard side of the ballast tank.

Anyone else encounter these symtoms?

On edit: It skips around all the time, faster when underway. I don't think the part of the boat under the dinette gets out of the water at any time.

Thank goodness I used plumber's puddy; if I'd followed Humminbird's directive to use only epoxy, I'd be looking for another puck.

[Frank C]

Anyone else encounter these symtoms?

You mean at speed, like when planing?


Edit to Add:
Just remaining "in the water" might not be good enough. If it's reading too close to the planing threshhold, then it's trying to read through too much turbulence. The best reliability I ever had with the sounder was mounted at the transom ... might go back there again.

[paj637]

I placed my transducer just aft of the stbd aft dinnette seat. Starboard outboard of the battery cover. Right against the hull by a stringer. I used the chunk of wax worked free of bubbles and seated the transducer in the wax (about 1/2" thick) adjusted the transducer for deadrise of the hull. Lots of flexibility for adjustments. I used the rest of the wax to build up around the transducer for holding power. It works great, ballasted or not. I have the Hawkeye depth gauge and mounted the gauge on the pedestal by the tach. We'll see how it works in the summer. But if it does sag from temperature, I'm only out a buck fifty for my temp setup for trial.. Also, this method can be used for trial setup. then go permanent when you figure out the best location.

[Craig LaForce]

I put mine under the aft berth and it works fine. You certainly don't want it to shoot through the ballast tank, so pick a low spot by a stringer to make sure it is the outer hull. I just put a little shot of some polysulfide caulk under the tranducer and smooshed it down good so it was a thin layer with no air voids. Also, if you are not getting a reading, you might try changing the gain setting on the depth finder. Mine has 5 different gain setttings.

You might need some 5200 remover to save the transducer if 5200 was applied. there are a couple products that help with removal.