Repair, Tools & Materials

Testers evaluated sandability, resistance to sag, cure time, and adhesion using sample fiberglass panels with 3-by-3-inch test swatches. The fairing compounds were applied and cured in temperatures ranging from the low 60s to the mid-80s. Each test was repeated three times, and the results were averaged. The shaping test involved closely timed periods of even sanding using a block sander and new sheets of 80-grit sandpaper. Testers observed each materials tendency to clog the sandpaper, and measured the volume of accumulated dust after four minutes of sanding.

Epoxy fillers can be used to fix surface imperfections or for reshaping appendages like keels and rudders to make them more efficient. The smaller the surface imperfection, the less viscous the fairing compound should be. When filling deeper holes or voids, check the manufacturers recommended thickness per application. It may take two or more coats to achieve the necessary thickness. Applying filler too thickly can cause it to sag or will result in an incomplete cure.

One of the more popular uses for fairing compounds is for shaping underwater appendages like keels and rudders so they are more efficient. Adjusting the NACA (National Advisory Committee for Aeronautics) profile, or airfoil shape, of a fin keel or rudder can create more lift to enhance windward performance. Altering the trailing edge can yield similar improvements.

How much load does a keel bolt or a winch through-bolt put on a hull or a deck? How thick should the laminate be at these bolt holes? How big of a backing plate is needed?

Once upon a time in Tasmania, a skipper faced a daunting task: install a three-bladed, folding propeller without hauling out the boat. The underwater job would require an adhesive to secure some of the bolts, but which adhesives that were already on board would work best under water? To find out, PS contributor Jonathan Neeves decided to run a little adhesives test of the three products he had on hand-all commonly found at chandlers worldwide under the same or a similar brand.

Over the years, weve stressed the importance of keeping a close eye on stainless-steel sailboat hardware and why pitting, crevice-corrosion, and galvanic action are the enemies. But we may have downplayed the need to be aware of how plain old ferrous-metal oxidation comes into the picture. Mild steel and high-carbon steel are even more prone to corrosion, and despite the fact that the oxidation is far easier to spot on these metals, this ticking timebomb somehow gets ignored.

For this comparison of synthetic teak options, our first concern was ease of installation. The manufacturer typically carries out the hardest part-welding the panels together to achieve the correct dimensions. The ease of gluing our test panels to a simulated fiberglass deck was similar for all five test products. The difficulty of your own project will depend on how much work the manufacturer does in terms of measuring, assembling, and fitting the panels.

With a little imagination and some inexpensive materials, you can put together a leakproof mast boot in a few hours. 1. Roofing Rubber One reliable boot sealer is self-adhesive ethylene propylene diene monomer (EPDM), a common rubber-membrane roofing material. Sold at local building supply stores, the rubber is black in color and comes in a roll that is 5 inches wide. (Dont confuse it with ice and water shield, which is much thinner.) Peeling the plastic backing from the underside of the EPDM material exposes the sticky side. Arrange precut strips prior to permanent installation. We suggest using American-made products as the imported stuff doesn't adhere well to itself.

When it comes to onboard water tanks, we prefer stainless, fiberglass, and even roto-molded tanks (in that order) to aluminum ones. Aluminum tanks tend to pit and corrode over time, often needing to be replaced. The insides of the two 60-gallon aluminum water tanks in our 30-year-old Valiant 40 were more like a nasty moonscape than a drinking source. Their surfaces were pitted and rusted from what looked like a reaction to long-time use of chlorine.

Gelcoat provides a fiberglass boat with a hard, water-resistant protective shell. When new, its polished and waxed to a bright shine, but after a few years of facing the elements-especially damaging UV rays-gelcoat will begin to oxidize and turn into a dull, chalky film on the surface. There are a few ways to remedy an oxidation problem (see Tips & Techniques), but for this article, we focused on coarse and medium-coarse rubbing compounds, which can be buffed on to remove the chalky layer and fine scratches. The tests evaluated ease of use, ability to remove oxidation and scratches, and whether they left swirl marks; testers also considered price, availability, and eco-friendliness.