How To Repair Boat Deck

Concluding calendar month nosotros looked at the effectiveness of injecting resin to repair damaged core sections (see "Can Gum Injection Fix Rotten Core," PS July 2022. This calendar month we'll review the more than robust repair option—replacing the bad core.

The factory skimped on resin when laying upward the internal peel of the ballast locker hatch on our Corsair F-24 test gunkhole. The goal was to save weight, only the result was hundreds of pinholes, which over the course of thousands of warming and cooling cycles, sucked in a substantial volume of humid anchor locker air. The core became clammy, bacteria moved in, and the balsa decayed to the consistency of garden mulch. Small wonder the hatch bent noticeably under foot.

Fortunately, the skins had non notwithstanding cracked. The other positive was that the hatch could be taken home for renovation, and that makes whatever chore easier.

When repairing deck core, piece of work can proceed from either the interior side or exterior side. Working from the exterior means your repair will need to friction match surrounding pare, whereas interior piece of work is usually hidden from view.

For deck repairs, working from the outside ways that gravity is on your side. The quondam cadre doesn't country on your face equally yous remove it, and bonding in new core material is straightforward.

Working from the within requires removing interior liners and modifying your laminating technique. Larger jobs tend to favor working from above, while small jobs go faster from inside. Information technology all depends on geometry. In our instance, nosotros simply flipped the cover over.

We cut away the skin using delicate, shallow cuts with an bending grinder. A vibrating multi-tool with a carbide blade is handy for small areas. The skin was then peeled dorsum using a dry out wall knife and a pair of pliers.

If it is undamaged and y'all are working from the peak side, save this for later on reinstallation. It will preserve the non-skid blueprint and smooth curvature in the corners. Even when you are careful, thin skins are often destroyed during removal procedure, which ways you'll take to laminate a new one—something to consider when deciding which side to work from.

Whichever method yous choose, be certain to wearable gloves while laminating. Change the gloves every 10 minutes or whenever they begin to become viscous; if glass fibers are sticking to your fingers, you demand new gloves. Likewise, have a stack of disposable brushes and polyethylene spreaders available.

Cleaning Out Old Core

Some of the old core will fall out, bringing condolement that you are doing the right thing. Some will come out with a scraper. We've constitute a wire cup castor, in either a cordless drill or angle grinder, makes fast piece of work, with less risk of cutting into the second skin than with vigorous utilise of a scraper or chisel.

You lot don't demand to remove undamaged cadre; when it gets really hard to remove, you lot're probably done. We left some core, afterward determining that it was similar new and that we couldn't remove it without dissentious the pare. Let the panel to dry.

Bow Hatch Core

1. A cutting wheel was used to trim the outer laminate to access the cadre.

2. The outer laminate easily pulled way to reveal the rotten core.

3. The new bow hatch is improve than new, stronger and impervious to water.

Bonding New Cadre

Yous can use either polyester or epoxy resin (see Inside PS web log post "Epoxy Versus Polyester Resin"). If you lot've worked with neither before, do on some sample laminates.

Some sections could exist solid glass instead of core. Lay those areas up with cloth or possibly Coosa Bluewater 26 (come across "The Multipurpose Core," PS February 2022). For cored areas, glaze the sections of replacement cadre with resin thickened with colloidal silica to a peanut butter consistency. Printing into place with a grooved laminating roller.

Use lightweight cores for overhead panels. Plywood is not recommended. Marine core is typically scored with kerfs and attached to a scrim backing so that it can follow curves. If the bend is concave, the kerfs will open the bullheaded side, so be certain to apply enough thickened resin to make full these kerfs as they open.

There is no reason to apply cadre in large sections, since it is scored anyway. Small sections, generally not much bigger than 6 inches foursquare, are easier to manipulate. Cutting smaller pieces to fill the larger gaps, and then spread thickened resin over the entire area using a flexible spatula, forcing it into the remaining hair line cracks. Allow to cure.

Utilise 60-80 grit on an orbital sander (or a disk grinder with a very lite bear on) to sand the new core smooth. Even if you matched the original core thickness, there will exist irregularities resulting from bumps of sometime resin and angles from the core.

Laminate a replacement skin, matching the original schedule. Several layers of 17-ounce biaxial textile with ¾-ounce mat attached (1708), followed by a single layer of six-ounce finish cloth is common on cruising boats. Smaller boats may use only a few layers of six-ounce finish cloth. Bevel the core edges to a ten:1 taper.

From the Inside

If you are working from the inside on an overhead console, lay the cloth on a plastic disposable work surface and pre-saturate the fiberglass cloth, using a squeegee and roller, before placing on the ceiling. Some like to do this on a bench exterior the boat and carry the sections in on waxed paper.

Don't attempt to saturate the cloth directly on the surface; the resin will drip all over you and the glass will keep falling off.

Rub the pre-wetted laminate down firmly with gloved easily and a roller until information technology begins to cure. If applying more than a few layers overhead, let the initial layers to gel. This prevents the whole mess from falling off in a mucilaginous pile. Allow to cure.

Use vinegar to wipe surrounding areas that were not covered with drib cloths, being careful not to go whatsoever on the bail areas.

From the Exterior

If you are reusing the onetime deck skin, carefully grind the core to fit the original skin, test fitting frequently. Yous volition add together thickened resin to bond and fill low areas, but there can't be any loftier spots and information technology is best if the fit is very close.

Unlike a new peel, y'all won't be able to curl information technology in for a perfect bond. This is why we dislike this method other than for very minor sections. Press the skin in place, weight it down it with sand numberless, and hope for the best.

Finishing and Cleanup

If you are working from the inside, all that remains is to grind information technology reasonably smooth and replace the liner or paint to lucifer. If y'all worked from the outside, bevel the joints 10:ane with a manus grinder, add fiberglass tape to match the original thickness, and finish with gel glaze or pigment.

Clean your tools with vinegar. Equally long as the cure is non too far alone, vinegar stops the chemical reaction and eliminates the stickiness, assuasive clean-up with lather, water, and a brush.

PS Technical Editor Drew Frye is the author of "Circumnavigating the Delmarva—a Guide for the Shoal Draft Sailor," available for Kindle through Amazon.

Source: https://www.practical-sailor.com/boat-maintenance/step-by-step-core-panel-fix

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