Depth meter transducer location

[David]

I have a '88 H33.5 in which I am replacing the depth meter and transducer. The transducer is bonded to the inside of the hull approximately in the rear portside just off the centerline behind the engine. (appx. 25 feet aft). I am considering mounting the new transducer beneath the forward V berth for ease of mounting and also to get depth data more forward to possibly avert a grounding situation. My concern is that pitching may adversley affect the accuracy of the data as compared to mounting more amidship where pitching would be less of a problem.... I plan to fabricate a housing filled with mineral oil in which to mount the new transducer inside the hull. What do you think?? Any suggestions or feedback would be appreciated.David'88 h33.5"South Wind"

 

[Colin]

Mine is under the vee berth.

The depth transducer in my 335 is mounted under the floor in the vee berth. Like the location as it it well forward and easy to access.

 

[Clyde Lichtenwalner]

Pitching

I can't imagine a situation where pitching will cause an error large enough to be of concern. If you are in water so shallow that you are close to going aground (4.5' or so for your boat?) you will not normally have a chop steep enough to create error larger than .5 foot or so. If you are riding a power boat wake or running a shallow inlet all bets are off, but having the transducer forward rather than aft is going to be of little consequence. If you are close to dragging the keel on the bottom and a wake causes 1' of up and down motion, you are going to hit bottom no matter where the transducer is located. I have yet to have a need for such great accuracy in deeper water.

 

[Bill O'Donovan]

I'm with Clyde

You'd have to pitch-pole to get a reading that would make any difference, by which time you'd have a much greater problem than the correct depth.

 

[Victor Robert]

Let us know the result

I am inclined to agree that I would like to know about an obstacle sooner rather than later (i.e. before the keel touches it). I have relied on this feature in the Bahamas when I had to nudge shoals at low tide to find a way through because the chart was too vague.Is the transducer you are using designed specifically for hull surface mounting ? I have been researching this method and a number of people have said it is somewhat hit and miss because it depends on a uniform density of the hull material at the point you mount the transducer (i.e. no air pockets or poorly saturated cloth). Please let us know how you did it and the results.

 

[Pops Landing]

Tranducer mount

There is lots of stuff in the archives about mounting an internal transducer. The best solution that I have seen is mounting it in slow set epoxy (slow set because it allows more time for the air bubbles to escape). You can tell if it is a good spot by shooting through a zipock bag filled with water between the transducer and the hull. When you find a good spot, build up the dams needed to contain the epoxy, level the transducer and mix it up real slow (the epoxy). Butter it on the bottom of the transducer, fill the dams and slide it in sideways, being very careful to not let air between the puck and the hull. Thats what I'm going to do.

 

[Del Wiese]

use transom mount transducer

I had good results on a previous boat with using a transom mount transducer and fastening it to the hull with silastic type sealant. I fastened it just behind the keel because this was a good flat area of the hull. Worked great, manufacturer told me I was losing some sensitivity at great depths (hundreds of feet) but I was more interested in the 10 feet and less depths.