M26swing: where mount a shoot through the hull depth transducer? (newest project)

Nov 15, 2020
30
Macgregor 26s Bay City Michigabn
Probably won't work to shoot thru the bottom water tank as an air pocket will disrupt it. The PO mounted a stern transducer with a Dragonfly 5 fish finder that probably gives depths but its at the stern, a bit far from the bow.... may have to use that one but I'm not sure how far forward it reaches in skinny water.
 
Jan 4, 2006
6,444
Hunter 310 West Vancouver, B.C.
See #7 for testing your hull for an in hull transducer.

 

AndyVS

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Sep 4, 2015
56
Corsair 31 UC 179 Port Sanilac
I have mine mounted in the floor of the laz. I used toilet wax to keep it in place.
 
Nov 15, 2020
30
Macgregor 26s Bay City Michigabn
If you mounted the puck in the laz do you feel it shoots far ahead enough to avoid shallow water as the bow heads into it? What's been your experience? Thanks guys for the contributions, so helpful to learn each other's experiences, yup thanks!
 
Jan 19, 2021
7
Macgregor 26D Puerto Penasco
Mounted my Hummingbird puck in the laz; bedded in silicone. Tested with a lead line and seems fairly accurate. Installed the Hummingbird while in the Sea of Cortez so haven't had to worry about very shallow water. No question your ability to see depth under the bow will be hampered. I get real cautious and slow way down when reading 15' or so of unfamiliar water so hope to avoid that "blind" spot 20' in front of me.
 
Nov 15, 2020
30
Macgregor 26s Bay City Michigabn
Your approach with the Hummingbird seems sound and careful enough in navigating safely... seems like a realistic solution with the water tank so far forward in the bow.. thanks!
 
Mar 15, 2021
51
Macgregor Venture 22 Brooklyn
I have mine mounted in the floor of the laz. I used toilet wax to keep it in place.
I have heard of toilet wax before for shoot through transducers. Can I get some details on this? I tried a shoot through on my Ericson with no joy. I may mount it in my Venture if I can make it work. I would probably put it at the aft end of the vberth if it works.
 
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Nov 15, 2020
30
Macgregor 26s Bay City Michigabn
Probably best not to shoot through the water ballast tank as there will probably be a bit of an air pocket above the water screwing things up....
 

AndyVS

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Sep 4, 2015
56
Corsair 31 UC 179 Port Sanilac
Toilet wax or plumbers putty are easy to work with and not permanent. Easy to reposition if you want to move the transducer.
 
Mar 15, 2021
51
Macgregor Venture 22 Brooklyn
@AndyVS what do you do with the wax? Melt it and shove the transducer into a blob of melted was on the hull before it cools?

I have a pound of high temp parafin left over from another project would that work?
 
Nov 15, 2020
30
Macgregor 26s Bay City Michigabn
Good! I missed that it was a V22, give it a try, I like the idea of plumbers wax as you can move it if the depth gizzmo is n't doing it's thing.
 

AndyVS

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Sep 4, 2015
56
Corsair 31 UC 179 Port Sanilac
I wouldn't know if parafin would work. Toilet ring wax and plumbers putty have the right consistency right out of the container.
I sanded the hull a bit first just to smooth it. I cut a square of wax a bit larger than the tranducer from the ring with a knife and put it on the spot and pressed the transducer into it so the wax comes up around the sides to hold it. Occassionally, something I drop in the laz will bump it loose and I just push it back into place. It been there 5 years, stays in place when outside temps get hot.
 
Mar 15, 2021
51
Macgregor Venture 22 Brooklyn
@AndyVS thanks so much! It sounds like the parafin will not serve. I will buy a wax ring when I give it a try on the V22. I tried with vasoline as a test on my Ericson 27 with no joy. I am wonder if that was because the hull was too thick. It seems to me my Ericson is built much heavier than the V22.
 

Macboy

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Aug 8, 2014
254
Macgregor 26S Sherwood Park, Alberta
As I was making my way through this thread I couldn’t help but wonder why we shouldn’t mount the transducers beside the ballast tank midship or even up front? True it won’t be as accurate as a centreline mounted aft installation when heeling becomes a factor but wouldn’t we mostly be under power or light wind when navigating super skinny water? So the boat would be mostly upright anyway.....
 
Mar 15, 2021
51
Macgregor Venture 22 Brooklyn
The transducer for my dead sounder on my Ericson 27 is mounted through hull forward under the V berth just to the port of the hull centerline. I never had any issues with inaccuracy when under sail. The depth displayed was always within what I would expect based on the charted depth.

I wish the display on that unit had not died. I hate being without a sounder.
 

srimes

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Jun 9, 2020
211
Macgregor 26D Brookings
Probably best not to shoot through the water ballast tank as there will probably be a bit of an air pocket above the water screwing things up....
The tank should be full. Any motion should work the bubbles back to the vent. Try it was toilet wax and see if it works.
 
Mar 15, 2021
51
Macgregor Venture 22 Brooklyn
I do not have a tank. Is there an inspection port on the tank that could let you mount the tranducer inside the tank and run the cable out a sealing gland?
 
Nov 15, 2020
30
Macgregor 26s Bay City Michigabn
wow, never thought of that...its a "new" boat to me, have to snoop around and see what I can find.... quite possibly a great idea, thanks!