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raynemacher
04-02-2007, 11:08 AM
Has any one ever mounted a thru hull depth transducer on the inside of a wooden boat similar to mounting in a fiberglass boat? The receptical I have is to short and a longer one is not available.

nedL
04-02-2007, 11:18 AM
In short ... It won't work. -- Fiberglass, being a solid material (assuming 'no' air bubbles) will transmit the sound waves of the transduceer quite well. Wood, being a porous material will not transmit the sound waves of the transducer. It's kind of like the difference between tapping on one side of a concrete wall with a small hammer and hearing it on the other side(fiberglass) vs. tapping on one side of a mattress with a small hammer (wood) and trying to hear it on the other side. --- I know the theory is different in this example, but I think the comparison is reasonable.

paladin
04-02-2007, 11:30 AM
How thick is the hull?.......I used 2 transducers on Tana Mari.....one on either side of the keel, connected by a mercury switch that selected the proper trasducer depending on which way the boat heeled....
Find a good solid area in the hull and remove a section about the diameter of a 2 pound coffee can....taper the hole inside and out. Cut out Fiberglass, not one of the plastics like xynole or vectra, and make a plug, with larger pieces lapping the inside and outside...make the inside at leats 8 inches in diameter of 3-4 layers of glass. Using the end cap covers of some 4 inch or so PVC pipe make a fiber glass replica. Cut a hole in the top to mount the transducer. Also make a hole for a fill pipe with a plug. Mount the transducer inside and epoxy it down centering it on the fiberglass plug. Don't gorget to wash the face of the trasduce with JOY liquid detergent, then add a few drops to the water. Close the cap. activate sounder. The JOY destroys surface tension on the transducer face.