Spray Deflector Repair

[Gadzooks!]

I've proved several times that docks are stronger than the MV34 spray deflectors on the bows. After having no success in buying replacements, I undertook to do it myself.

Ingredients for the fix:

1. West System 150 resin, 206 hardener, 404 filler, and 406 filler.
2. Aluminum 1" x 1" angle. Bought 6 ft length, used about half.
3. 3M Premium Marine Filler and creme hardener.
4. six or eight 3/8th inch self-tapping screws.
5. spray paint

Tools needed: electric hand grinder, Dremel tool and bits, common hand tools, clamps, electric sander (detail sander works best - mine was a Bosch with the little rounded-triangle slap-on sandpaper sheets)

My Procedure (improvements possible)

A. Grind off broken areas down the the flange base. Don't grind off the base or you'll be into gel coat repair.
B. Make an accurate pattern of the base shape where the new flange portions will go. I used cardboard which worked well making the pattern. I also used it in the reconstruction itself. Was a bit flimsy for that stage. Would have been better to transfer the pattern to thin plywood.
C. Cut the aluminum to desired lengths. Saw slots in the horizontal part to allow it to be bent around the point of the bow. I sawed one every half inch over a 4 inch span.
D. Fasten aluminum pieces to the bow. I drilled hole for screws, did shallow starter holes in the base, then put a thin coat of epoxy on the interior vertical surface of the pieces. Finally, attached the pieces to the boat with the screws to hold them there while the epoxy cured.
E. Slather epoxy with filler added to achieve non-drip mixture (about like peanut butter) onto the angles. Try to approximate eventual shape (the important parts are the ones visible from above). Most of the strength will be in the epoxy.
F. Sand off the parts of the hardened epoxy that fall outside the desired shape. Repeat E and F if needed.
G. Apply 3M filler to more closely approximate desired shape. Sand as above. Repeat, probably more than once, at least in some spots.
H. Mask off and paint.


Some mistakes to avoid, and some things learned:

I had the preliminary clean-up grinding done at a yard, and did the rest of the work myself with the boat in the water. It would have been better to pay for a couple days more in the yard as the job would have taken maybe 25% the time, the end result would have been better. Next time the boat is out of the water, I'll do some more shaping and removal of excess. The deflectors are now fully functional but can use cosmetic improvement. It's not possible to do precision work when draped over a dinghy tube with your head at the boat's waterline while bobbing up and down with wave action. Very labor intensive and frustrating.

The deflectors really are needed -- on the trip home from the yard, spray came aboard like water from a garden hose.

I attached the aluminum pieces too high. Wound up putting more epoxy under them than on top. Also, some of the tips at the prow proved outside the flange profile and had to be ground off. The horizontal aluminum should be at the bottom level of the finished flange.

All in all, I'm pleased. And a little smarter albeit too late!

Photos available for anyone who wants to request via email.

[Bargain Bill]

I had this done by a local who has done some fiberglassing (not an expert).
He prepped the two 6-inch gaps and ground down and tapered the top and bottom of all remaining edges that abut the repair.

He then made a form using the center tube from a paper towel roll and taped it under the broken ends that remained attached to the hull.
Epoxy (pretty sure it was West Epoxy) was mixed, poured and molded to the form and shaped to follow the top curvatures - - leave it longer (sticking out) than needed.
After it hardened it was ground down to give a smooth finish and painted.

2 years and 1,000 hours later the 3 hour job (the boat was already on the hard) is holding well. And while it was the former owner who knocked out 2 teeth, I am much more aware of the spray rail when dealing with docks and anchor chain.

[Mary & Roger]

What about making them a little wider, especially on the inboard side of each hull??? Roger Comer, Teamwork