How To Remove Bottom Paint

To Strip? Or Not to Strip?

All things come to an terminate, including bottom paint.
Here's how to cope with antifouling separation anxiety.

When she was young, your boat had a bottom that was equally smooth equally a babe's, with not a dimple or a blotch. Your fingers slid beyond the surface similar it was silk. But not anymore: Now her once-flawless gelcoat is subconscious past layer upon layer of dead antifouling paint, like rouge on a dowager's cheeks. Your boatyard manager says it's time to strip her lesser and start fresh. It'll brand her slick as an eel, he says; she'll go faster and burn less fuel. Heck, she'll exist similar a kid again.

Your checkbook quivers at the thought. Is such a matter really necessary?

"Absolutely non," says yacht designer George Buehler. If the paint's notwithstanding sticking, information technology'due south non flaking off, and information technology's nonetheless keeping the critters away, in that location's no reason to spend hard-earned dollars and/or elbow grease removing it." Does the weight of thick paint picture and its corresponding rough surface have any real event on the performance of a displacement-speed cruiser? "I can't imagine it would exist measurable," added Buehler. "Some racers burnish their bottom paint with 600- or 800-grit wet emery cloth to smooth information technology to the nth degree, simply only the virtually anal of them."

Don't Spare the Sandpaper

Nevertheless, virtually all antifouling pigment volition eventually fail. Jeremy Dolan, Technical Service Representative for International Paint LLC, manufacturer of Interlux products (world wide web.yachtpaint.com), said that over many seasons and many repaintings, the accumulated weight of the pigment itself volition crusade it to fleck off. And in one case the paint starts to fleck, it has to be removed. How can you tell when the paint's getting too thick? "If at that place'southward an bodily ledge against the masking tape at the waterline, it's time to at to the lowest degree sand information technology to accept some layers off," he said.

Dolan explained that an energetic attack with 60-dust newspaper can coax more years from your lesser, and let you schedule the consummate job on your own terms—maybe you don't have the budget for information technology this yr, or the task will filibuster launching your boat, and y'all'd rather practise it next spring. And you might brand a better deal with the boatyard if you piece of work with them on scheduling: Glen Billings, proprietor of Billings Media Blasting (www.billingsblasting.com) in Glastonbury, Connecticut, works for boatyards throughout New England. He said that yards usually prefer the bottoms stripped in the autumn, so they tin prep and recoat as weather permits over the winter, when piece of work is scarce. Boat owners tend to wait until spring, when everybody's decorated.

Notation that every paint manufacturer recommends sanding before recoating to remove some of the dead paint and ameliorate adhesion of the new coat. Information technology'south a directive that's overlooked as often as information technology is followed, simply it will earn you more than years out of your lesser. Boatyards don't like sanding considering it takes fourth dimension, and bottom painting is priced per foot, non per hour; sanding isn't rough just on paint, but on profits, likewise. And the paint sticks fine without sanding—until information technology doesn't. Today, most yards insist on doing all hull work, for environmental, liability, and economical reasons, but if you can find a thou that lets you lot practice your ain work, use your own free labor to prep your bottom properly. Then pay the thou to paint information technology; they accept to make a living, also.

How To Strip Your Lesser

There's no hush-hush about the best way to strip your bottom: Utilize your checkbook. For all but the smallest boats, it's a job best left to professionals with the necessary equipment and expertise to get the task washed quickly, thoroughly, and without hassles. The final thing you need is the guy next to yous in the yard calling the Green Constabulary because y'all didn't dispose of stripped paint in an environmentally correct mode. (The stuff is toxic, later all.)

If you insist on doing a strip chore yourself, your options are mechanical (scraping and sanding) or chemic, using a liquid stripper like Interlux Interstrip 299E, Soy Strip (www.franmar.com), or a paste/paper product like Peel Away Marine Strip (dumondchemicals.com). Dry scraping is torture, chemical stripping is messy, and if you accept many layers of paint on the lesser you'll probably have to apply peel products a few times.

Whichever method you cull, wear eye protection, and a pro-quality combination respirator that filters both dust and fumes—don't rely on a cheap paper mask. Once the paint is off, you'll exist using solvents to clean and prep the bottom, and you'll appreciate the respirator.

For my money, diggings is the fastest, nearly efficient, and most economical mode to remove antifouling paint. A pro like Billings tin strip your gunkhole in a 24-hour interval. He uses crushed walnut shells to remove the soft antifouling without damaging the harder gelcoat or barrier glaze underneath. The walnut shells will sometimes open up blisters, but if gunkhole pox is an issue, Billings volition use sand instead to open them up. When the blasting is done, there should exist only a tinge of color left on the hull, he said, the consequence of the first coat of antifouling existence "washed properly"—laid over primed gelcoat or a tacky barrier coat to class a strong chemic bail. If you terminate up with overnice make clean gelcoat, the paint wasn't applied correctly in the showtime identify.

Some professionals "dry out blast" with simply air pressure as a propellant, while others "slurry blast" with water to keep the dust down. Billings prefers dry blasting because it makes clean-up easier: He tents the bottom to corral the dust and spent abrasive, and lays downwardly plastic sheets under the boat to catch the debris; when the job is done, he simply rolls upwards the plastic and disposes of it. With wet blasting you have to comprise the water, too, he said. "You tin can't go along things clean enough." (Proponents of moisture blasting say most of the water evaporates away, and at worst you lot get muddy debris.) Bottom line is, it's the equalizer's option: As far every bit the job is concerned, both methods go 'er done.

While you don't have to become a equalizer and strip your own bottom, learning a bit nigh it can assistance you find the right expert, or the correct thou, to do the task. MMLJ Manufacturing has been building sandblasting equipment since 1941; their Dustless Diggings (www.dustlessblasting.com) process uses h2o and recycled crushed glass to strip the surface. A visit to their website volition requite y'all a quick instruction in blasting.

Visitor spokesman Ryan Detablan said MMLJ will sell you lot a standalone dustless equalizer if you're serious about doing your own bottom stripping. Model DB800 is just right for most applications. Information technology comes with the compressor, blaster, water tank, and all associated gear mounted on a trailer; just hook it up to your truck and drive abroad. Toll is about $49,500, though, so maybe you'd rather just hire a pro. On the other hand, there are a lot of bottoms out at that place overdue for stripping.

This article originally appeared in the April 2022 outcome of Power & Motoryacht magazine.

Source: https://www.powerandmotoryacht.com/maintenance/how-to-strip-your-bottom