Wetmount install condundrum, Loctite Putty?
 

I have a Airmar P79 transducer that I want to install in my Hobie Outback. I've done some research on this for adhesives and it seems the overall success has been attributed to using Marine Goop. The problem I have is the case the transducer sits in ( similar to Bob's 3-4 inch PVC Pipe transducer case for his wetmount design). Anyway, I've tried twice now, and the thing I cannot seem to do is get the bottom of the well to sit flush with the keel.....due naturally to the curve of the kayak. I know some of you have used a sander to shape the bottom of the pipe, but I'd like to avoid that if possible mainly due to not have a sander to craft the curvature. There is no way I can build up the marine goop enough to fill that 1/4 inch gap at the front and back of the cradle ( the goop just doesn't have enough "body" to do this) I was thinking about using this LOCTITE putty to fabricate or mold a thin roll into this crevice to fill the space. This will allow me to use the existing Airmar P79 cavity well to house the mineral water and transducer. Any suggestions or advice?

mount
 

i have the same problem on my hobbie what i did is i just bought a wood hand saw and saw the side of the pipe just enough to follow the curvature of the hull, then i use goop to fill in the seam. i took a marker mark the inside diamiter of the pvc to where you want to install it, then take the goop put a good size bead just ouside of the mark you just did, put the pvc on top of the goop press and smooth out the excess and let it dry, then do a leak test just fill it with water. and i use a rubber cap that i screwed my tran on it havent leak or looses water going on for 3-4 months now.

Here is the Airmar P79 transducer.

I guess I could sand down the cradle........just didn't want to ruin it since I can't easily replace it. I'd have to then go to a full PVC Pipe install if things got sideways at that point. I did use a marker to outline the circumference of the cradle.....but when I laid down the bead, it just "ran away".........Initially when I tried this, I thought I had built up enough around that crevice........but the water test confirmed the opposite.

Durwood, I don't know how "pretty" your install needs to be but here is a solution I used.

Buy a cheap 99c tupperware flexible clear container, the kind that moves easily in your hands. (I use one about 4" by 8") You can very easily cut out the bottom and shape the walls of the "no bottom container" with a pair of household scissors to match the contour of your hull.

Buy some 5200 slow cure adhesive at BPS or some marine store. Goop did not work as well in my opinion.

Rough sand the area of application with coarse grit paper. Wipe it down with some alcohol.

Trace the outline of the container and squirt a nice bead. Lay another bead around it , inside it, next to it, SQUIRT away! The 5200 is white and very flexible, does not peel or pull away from the hull.

Now mickey mouse a couple of plastic ties to hold the transducer in the container.

I think that many of the problems people have is because of the RIGID container or pipe which does not flex or give with the movement of the boad hull.

Be careful of using any kind of rigid material to attach the well to the hull. Kayaks flex quite a bit and anything rigid will eventually break free. If you cannot shape your well so that it comes fairly close to the contours of the hull, you will probably never have much success with the wet mount.

I know that this may come as a surprise to some but I have switched the the grease mount. My wet mount works perfectly but but a few months ago, Humminbird sent me their grease mount kit to try. It failed miserably but only because their supplied adhesive did not work. I ended up gooping their mounting bracket to my hull and the system works very well.

I cannot say that the grease mount is any better or worse than the wet mount as far as the image quality but this system is really an install and forget it mounting system. No longer do I have to worry if the water in my well has evaporated or leaked away.

For those with a hull shape that is difficult to fit to a rigid well, the grease mount may be a better way to go. The well seal does not have to be perfect. In fact you can probably use a flexible material to make the well and it only has to be deep enough to hold the transducer in place.

The only thing you have to worry about is if the material you make the well from will play nicely with the grease. Some plastics, and rubber materials will degrade after contact to oils and greases.

Although I have not tried it, I think the perfect material to make a grease mount well from is some sort of closed cell foam such as recycled tire rubber, neoprene, (wetsuit material), or EVA, the lightweight foam use in some playground applications. The material is easily cut and glued to the hull. The unknown is how it will hold up to the grease.

If someone wants to experiment, I have most of these materials on hand and plenty of grease. I would be happy to help with an installation. Please PM me if you would like to drop by my house some time and give it a try. I am in Encinitas.

Bob

what type grease you using??
im using the foam transducer blocks (two stacked on top of each other) purchased from fastlane for a wet mount and would like to try the grease mount with the foam blocks.


thanks for the offer but i think i'll pick some up at the local store if available.

I just bought a can of Marine Grease from Pep Boys. It seems to work fine as a medium and does not melt even when it get to 150 degrees inside the kayak.

After you try this setup, please post any observations regarding how the foam holds up to exposure to the grease.

Bob

Bob

oil!
 

I've used a version of the grease setup in boats, It works very well. I've even heard of guys useing hydrolic oil.

Hmmm... very interesting...

will do, im on call 24/7 for the next couple weeks and will report my results when i get off standby

Bob, take a look at these pics please.

This pipe should probably work fine providing you can get a good seal to the hull and find a cap that will seal. The rubber will flex to confirm to some moderate hull contours but not to something major.

I do like the idea of using a flexible well which should absorb some of the shock and flexing that the hull goes through.

Bob

I certainly hope so.......this stuff is fun.......but only to a point. Afterall, there is more to fishing right???? I'm going to try and shape the bottom to fit the countour of the hull a little bit better. If it doesn' work, then I've thrown out $6.00.......not the worst thing certainly.

I just used marine putty and silicone sealant to setup my wet mount, I'll know in the morning if it worked

if you have a revo, this is how you mount the transducer....very simple, no goop...I've had a few different types of transducers mounted this way in a couple different boats....works great everytime!!

see post 68.....do it and don't look back.

http://www.bigwatersedge.com/bwevb/s...?t=6394&page=4

Scallywag, I have the Outback, but the hull design near the mast section is essentially the same I imagine....the problem is I don't have that kind of transducer, mine looks like this.....not sure how I would fabricate a device to clamp on to it since it's round like a hockey puck......however I could just lay it down there inside the well and use something to keep it from sliding around....i looks like yours sitting on the hull practically. With the Airmar, I don't think I can get enough water into the hull for it to touch the transducer, there is about an inch or so clearance between the bottom of the well and where the transucer seats.

pics of the transducer

5200
 

use a cup of any kind, cut the bottom out, I use a pelican box with the bottom cut out, glue the sides of your cylinder to the bottom of the hull with 5200 available at any west marine. wait 24 hours, then go fish 5200 is without question the best adhesive for a water seal going. fill the cup with water and set your transducer in it. DONE

Thnx, sometimes I make things so much more complicated than they need to be....:rolleyes: