Boat Maintenance

Our boats are molded, heart and soul, from fiberglass resin. And while sailors will argue for hours over the best splice, multi-function display, or anchor, repairs or modification to the actual fiberglass structure are considered a black art. However, working with composite structures is not much more complicated than woodworking; it just requires a new skillset and a different bag of tricks.

Practical Sailor recently tested the strength of solid laminate with relation to the bolt passing through it (see PS, June 2016 online). We also tested several materials used to make backing plates when attaching fittings, hardware, and structural components to the boat.

Our deck core samples for testing duplicated the deck core of our test boat, a 32-foot PDQ catamaran. Some other boat cores will be more strongly constructed; some will be lighter.

The writers and editors at Practical Sailor are perpetual tinkerers-always looking for creative, do-it-yourself solutions to even the smallest onboard problems. We figure our readers likely suffer the same challenges on their boats, so were obliged to share such projects.

Breathing life into an older fiberglass boat always entails more work than was expected, but for a person with the time, skill, and do-it-yourself inclination, it is often worth the extra effort. The DIY approach makes even more sense when the boats structural quality and big-ticket components meet the grade, and the skipper and crew are ready to tackle the cosmetic makeover. These fairing compounds are perfect for structural and cosmetic fiberglass repairs.

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.

Ive had a bunch of friends troubleshooting battery issues lately. It would be really nice to have a chart that shows the battery voltage at rest and charging voltages for bulk/acceptance/float for lead/acid (flooded cells), gel cells, and AGMs.

Our 20-year-old Ideal windlass seemed a bit wimpy last fall, so we pulled it and took it back to the Ideal (www.idealwindlass.com) factory in Rhode Island for a rebuild. What a place! It looks like a set for a Charles Dickens movie. However, the work is great, and the windlass now seems to work as good as when it was new. The work was on time, and the cost was about a 10th of the price of a new one.