Easily Removable Sonar Transducer Stern Mount

Published date: September 17, 2023
Modified date: October 21, 2023
  • Boat Type: MacGregor 26X, Boat Type

Hi All!

We recently completed a mod to allow us to have a removable sonar transducer for our Mac26X.

Advantages to easily remove our sonar transducer
> when not in use
> minimize marine growth
> when trailering
> when backing into the beach
> when deliberately “tiding out” on the beach
> to be able to easily change out between primary and auxiliary systems (redundancy)
> to be able to swap systems between or Mac26X and our little runabout
> to avoid leaving the transducer perpetually out in the elements year round
>>> Importantly this was to be able to fully utilize the Side-Scan Sonar features of our primary chartplotter & sonar system that we couldn’t with our prior “within-the-hull” arrangement.

So let get started….

I utilized a section of cast aluminum TRAXSTECH “T-rail” 18 inches long that I mounted to our G-10 engine mount reinforcing plate we installed as part of our engine up grade. We used the mount plate attaching the TRAXSTECH to the stern by drilling and tapping full depth 1/4-20 threads into the plate. The screws were driven in with Locktite Green.
A bottom stop bolt was added at the base of the T-rail with Locktite Green.

I utilized a section of used spare STARBOARD to make the T-slot slider plate about 14 inches long to provide stable interface to guide & hold the outer mount plate.

Used SST #10-24 screws and SST Self locking nuts to make gap space between the slider and the outer mount plate. This allows adjusting the clamping gap to the T-rail.

The 24” outer clamp plate made from 3-1/2” PVC lumber board. Transducer bracket is mounted at bottom and a lift hole was made at the top. Router radiused cut edges.

Relationship between the slider plate and the outer mount plate was adjusted so that the transducer was protruding below the bottom of the hull the recommended 1/4-to-3/8 amount.

Transducer cable routed up and through the finger lift hole with UV clamps.

1 Complete install
2 New system & Old ballast mount
3-4-5 Clearance views
Remaining are perspective photos of the various parts for reference

So far so good!
Now I can remove the auxiliary transducer from Over Easy once the rain lets up…

Best Regards,
Over Easy :-):-)

Bit of an update on the actual 6 Day ICW Beaufort to Charleston and Back Cruise Trials conducted this past week.
The removable transom mount went perfectly!!!

✅All transponder functions worked as expected (accounting for the minor aspect with the engine lower unit echo reflection aspect discussed in prior posting)
✅Transponder was easily installed.
✅Transponder stayed in place.
✅Transponder was easily raised when desired.
✅Transponder was easily removed and stored.

Liked how it gave additional information about the regions to either side of the boat when in narrow channels.
Like all sonar transponders it still only really gives you information in a slice plane localized to the actual transponder itself.
Not much if any forward/aft look capabilities which is expected. Eventually I’ll figure out how to either bow mount a transducer or work out a valid “look forward” capability… but that’s another challenge for another day????).


Useful information

  • This site is not responsible for damage done to your boat.
  • When in doubt, consult a professional. Always comply with local and marine codes.
  • Dont drill holes in the bottom of your boat.
  • Happy sailing

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