Gary,
I stand corrected.

FWIW, if it were MY decision I would go with the Bronze; because it's, well
.. . . BRONZE !! {kind of matches my personality . . .}

All joking aside, if ANYTHING penetrates the hull {wood OR 'plastic'} I want
it to be the strongest possible material. Something that is 'plastic' or
Nylon can be shattered or fractured if it is struck . . . have you seen what
can float, just submerged, after a big storm ? In addition, anti-fouling
paints easily 'attach' to Bronze fittings. I'm not sure about barnacles &
Nylon, but I DO KNOW that 'slime' & algae WILL cover Nylon quite rapidly.

However, if you already have the Nylon transducer and want to use it, here's
how I would proceed. Make the penetrating hole about 1/4 inch LARGER than
the diameter of the part that will go THROUGH. Coat the cut edge with epoxy,
let it soak in a bit, then apply more, plus some fine weave Fiberglass cloth
{an overlapping 'collar'} this will SEAL the wood from water penetration,
plus stabilize the area. There should STILL be some 'slop' in the fit. After
it 'cures' for about a week, clean the area with warm water and a bit of
liquid soap, rinse well & dry. {this will remove any Amine 'blush'. 'Gun' a
LOT of RTV around the 'mating face' of the transducer {typically they are
inserted from the outside of the hull}. Carefully insert it - CENTERED - in
the opening. You want a LOT of 'squeeze out' up through the opening.
Carefully snug down the interior 'flange; NOT all the way - just get a good,
even 'squeeze out'. Let the RTV 'cure' for about 24-hours. NOW tighten up
the interior 'flange' and trim off the excess. You now have a 'Custom Fit
Flexible Silicone Rubber Seal' .

The wood is sealed from water inclusion by the epoxy/glass 'collar'. If
there is any slight movement or pressure, it will be absorbed by the RTV
Silicone 'gasket', rather than cause a 'point loading' on the transducer.
Paint won't 'stick' to the Silicone, but it comes in Clear, White, and I
think - Black.

Let me know what you think, or if you want clarification.

Regards & Good Luck,
Ron Magen
Backyard Boatshop
{who has put Bronze chocks on his foredeck, and a 7 inch Bronze cleat for
the mooring pendant}

"Gary Warner" wrote in message
...
Ron,

Thanks for the answer but I *think* you and I are talking about
two different things. Unless I'm not catching what you mean.

This transducer is NOT a Shoot-Through-The-Hull type mounted inside the
boat. (Also called an "In Hull Transducer" ?? )

It IS a THROUGH-HULL type where there is an actual hole cut in the wood.
The transducer has a "mushroom" head on it and a "stem." The "stem" is
pushed through the hole in the hull and the mushroom head sets outside the
hull.
SNIP