View Full Version : West Epoxy question

11-30-2012, 12:26 PM
I ask this question of all you Goop users like me , Thanks.
I want to glue a transducer to the inside of my fiberglass boat to shoot thru the hull, worked good on the old unit and want to do it like that again.
I plan to tape down a 5" sguare form and fill it with about 200grams or 7oz of West resin and Slow hardener that i have on hand to push the Transducer into and weigh it down until the resin cures.
Its been my experience that that much volume will flash of hot when contained in those dementions and would ruin the cure and the transducer also.
What do you all think?
Here is my plan, air temp will be between 45-50 degrees, mix resin and slow hardener and pour in form, push transducer into position and anchor, put lighted 100whatt bulb in bilge (2x2x2area approximate) to slowly heat the area to bring the temp above 60 which is the min for slow hardener to cure, direct heat to bottom of hull with radiant heat disc heater. Think it will work ? I won't hold anyone liable for there answers, thanks again.
Going to try it today after work so I'm on the edge of my seat waiting for opinions.

David G
11-30-2012, 12:42 PM
Go to their website. Download their book. IIRC, they give instructions on doing precisely what you intend.

11-30-2012, 06:29 PM
I can't find sounder or transducer in the PDF. http://www.westsystem.com/ss/assets/HowTo-Publications/GougeonBook%20061205.pdf

I'd fear that setting a transducer in a glob of epoxy would make it hard to replace.
Some transducers come in housings that bond to the bottom and permit the transducer to be removed and replaced.
I recollect hearing of setting a transducer in a glob of silicone. This would be removable.

Maybe someone here knows something about this .

David G
11-30-2012, 08:59 PM
I don't have time to dig it up, by I'm pretty sure I remember a section - with illustrations no less - about how to do this.

Or... perhaps it was an Epoxyworks (their periodic newsletter) article.

12-01-2012, 02:35 AM
Just call their tech support line. I've always had good luck with them. I too remember reading something about exactly this project.

12-01-2012, 02:38 AM
Here it is:


12-01-2012, 09:12 AM
FWIW-I have installed many shoot-through 'ducers with 5200/Sika adhesive without problem. Easier, quicker and you can remove/replace with a putty knife sharpened on a stone and a little elbow grease if need be.


John Meachen
12-01-2012, 05:18 PM
I remember some transducers used to be fitted into plastic tubes and just sat on a film of oil,olive oil if memory serves.The tube went in some time before the transducer got to the boat.

12-02-2012, 12:47 AM
I remember some transducers used to be fitted into plastic tubes and just sat on a film of oil,olive oil if memory serves.The tube went in some time before the transducer got to the boat.

Back in the day before sonar companies were offering shoot-through, puck style transducers we did this all the time to use a THROUGH-HULL transducer as as SHOOT-THROUGH unit. We'd get some PVC pipe of a diameter large enough to fit the transducer inside. Cut it a little longer than the 'ducer. Scribe and cut one end to mate to the hull deadrise at the mounting location. This was glassed in place using polyester resin.

Next, we'd drill out a pipe cap to fit the stem of the through hull transducer. Mount the ducer to teh cap.

Next, fill teh glassed in place pipe with mineral oi. We never thought of olive oil--you want something viscous enough that it wont aerate and create bubbles-- but it would probably work fine.

Put the cap and transducer on the pipe and secure with a blob of silicone at 12-, 3-, 6- and 9-o'clock. That made the setup serviceable, since you could remove the cap with relatively little effort.

Before committing to the install location , we always put the transducer in a plastic bag and fired up the unit to make sure it would work at the intended location. In addition to voids in the glass, you still have to be wary of the location of struts, strakes, intakes etc. Bubbles arent just a problem if they actually cross the face of the ducer; they disrupt the signal if they pass through the ducers beam.