Extend LPU Life with a Few Basic Care Steps

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The results derived from a professionally applied LPU topside refinish are as dramatic as the invoice that accompanies the makeover. The shiny, wet look and the protection it affords can last for years-whether its three years, five years, or nearly a decade depends upon how kindly the rejuvenated surface is treated. Two-part polyester urethane coatings such as Awlgrip II are tough, gloss-retaining coatings that will put up with some abrasion, but if you make it a regular occurrence, both the gloss and the paint will eventually go away.

Keep your topside paint healthy:

During application: Most well-executed LPU paint jobs begin with epoxy primers and fairing compounds as the underpinnings of a glistening LPU topcoat. When it comes to longevity, applying enough mil thickness of paint is paramount, and each paint manufacturer specs out a wet thickness or volume of paint per given amount of surface area by which the applicator can determine when enough material has been applied.

  • Cleaning: Regularly sponge washing the hull is the first step in preserving the topcoats shine. Avoid cleaning with scrub pads and gritty cleaners; this should be a completely non-abrasive effort. Many paint makers offer their own mild detergent, and weve found Awlwash by Awlgrip to be a very effective, completely non-abrasive cleaner. The purpose of these regular washdowns is to remove dirt and chemical residue transferred to the topsides by atmospheric deposition. Over time, such contaminants will diminish gloss and trap grit, increasing the abrasive effect that fenders have when they rub against the topsides.
  • Sailing is not a full-contact sport: More often than not, the decision to have the topsides re-painted has to do with localized damage that resulted from docking maneuvers gone awry, tussles at the starting line, or storm damage when a line gives way. Those who can avoid such bumps and bruises can nurse the gloss for many more years. Eventually the surface will need to be repainted, but if there is a minimum of dings, scrapes, and damage, and the primer is intact, the paint prep process will be much less invasive and the cost of extensive fairing will be less.
  • Wax On-Wax Off: After the first two or three seasons of washing and protecting the surface from winter-cover abrasion and line chafe, there’s often a need to tune up the gloss a bit. Although we’ve had good results with traditional carnauba based waxes (applied by hand only), US Paint, the makers of Awlgrip contend that these waxes can yellow or attract dirt, and offer little benefit. We suspect another reason is US Paint doesn’t like these products is that they worry about machine buffers, which makes applying these hard finishes so much easier, but can shorten the life of your paint job (especially if over-used). Our reason for using a traditional wax rather than a deeper-penetrating copolymer polish is that at some point, repainting the surface will be in the cards and polishes that reside deep in the porosity of an aging finish are hard to remove and can cause possible surface contamination.
    US Paint insists their product is easily removed with their solvents. Despite our own long experience, we offer US Paint’s guidance here. Their page “Maintaining an Awlgrip Finish,” offers more details.

    “Traditional waxes break down rapidly. The residue can cause the finish to appear yellow, plus it attracts dirt. This creates the need to maintain the wax, increasing overall maintenance. Traditional waxes which contain no abrasives probably do little harm to the coating, but offer no benefit. Awlgrip has developed Awlcare Protective Polymer Sealer 73240 for those who want to enhance their finish and need the additional cleaning power of a hand applied, dry wash product. Awlcare is a non-yellowing sealer that will protect your Awlgrip finish with regular applications.
    Hand applied Awlcare will not harm Awlgrip finishes and can easily be removed with Awlprep Plus T0115 (or T0340 Surface Cleaner in Europe) when it is time to repaint.

    Awlgrip topcoat only (G/H Line): Regular applications of Awlcare will help temporarily seal and restore shine to painted surfaces that have become porous due to age or mistreatment, helping to maintain a satisfactory appearance until there is time to repaint. Do not use polishing compounds on Awlgrip G/H Line topcoat. 

    Awlcraft 2000 and Awlgrip HDT: Awlcare Protective Polymer Sealer will help maintain the gloss on these finishes with regular applications, especially those which have been buffed or polished. Remember, Awlcare is only applied and buffed by hand. Never apply or buff Awlcare with a machine.

  • Breathe life into dull coats: Owners of boats with five- to seven-year-old intact LPU paint jobs that look dull but remain well adhered, can try rubbing out the surface with 3M Perfect-It rubbing compound and following up with a carnauba wax. In such cases, the gloss often can be readily restored, but as with older gelcoat, the new shine is derived from the smoothness of the surface and the wax, not the paint coating alone.
  • Repair care: Repairs to two-part LPU coatings are a true test of product awareness and applicator talent. The challenge lies in blending the old and the new, and blending the circumference known as the overspray region. Matching color change and gloss variation is even tougher than automotive work. The reason for these difficulties is the quality of the paint itself. Polyester LPU coatings are so tough that attempting to rub out the overspray line associated with a repair can result in too much heat and the dulling of gloss around the perimeter of the new paint. Picking the right time to buff back this boundary between new and old paint, and using the right rubbing/polishing products is a well-kept trade secret among craftsmen. Most love the 3M products Perfect-it, Finesse-it, and tried-and-proven red Rubbing Compound.

One of the reasons why AwlCraft and other slightly softer and more user-friendly acrylic-based LPU paints are growing in popularity is that they are much easier to repair and rub out than polyester-based two-part paints. Their longevity is good, but not quite that of old standby Awlgrip or new-kid-on-the-block Alexseal.

Alexseal, which also makes high-quality aliphatic polyurethane paints, explains to customers that acrylic paints are softer and even though they may be much easier to repair, they do not provide the durability and chemical resistance of the harder, molecularly cross-linked polyester paints. We plan to take a close look at Alexseal in our next round of topside-paint evaluations.

Darrell Nicholson
Practical Sailor has been independently testing and reporting on sailboats and sailing gear for more than 50 years. Supported entirely by subscribers, Practical Sailor accepts no advertising. Its independent tests are carried out by experienced sailors and marine industry professionals dedicated to providing objective evaluation and reporting about boats, gear, and the skills required to cross oceans. Practical Sailor is edited by Darrell Nicholson, a long-time liveaboard sailor and trans-Pacific cruiser who has been director of Belvoir Media Group's marine division since 2005. He holds a U.S. Coast Guard 100-ton Master license, has logged tens of thousands of miles in three oceans, and has skippered everything from pilot boats to day charter cats. His weekly blog Inside Practical Sailor offers an inside look at current research and gear tests at Practical Sailor, while his award-winning column,"Rhumb Lines," tracks boating trends and reflects upon the sailing life. He sails a Sparkman & Stephens-designed Yankee 30 out of St. Petersburg, Florida. You can reach him by email at practicalsailor@belvoir.com.

1 COMMENT

  1. Sadly I missed a couple of spots when painting my Mainship. On the advise of Epifanes they said tape of a trapezoid shape around the missed spot and repaint it. Blending will make it look like a kids paint job. It worked. Only I know where the patch is. And what a relief because we already have a couple of docking scrapes, one my fault and one a dock hands fault at a pump out. This monourethane will make my life much easier. I hate scratches in a hull.