The Right Way to Paint
A new generation of antifouling coatings promises better protection for running gear.
I once read a quote mistakenly attributed to Henry Ford: “Never invest your money in anything that eats or needs painting.” The actual author was a man named Billy Rose, and while I don’t know what he did for a living, I’ll bet that he painted boats in South Florida.
This region is undoubtedly one of the toughest environments for keeping paint on running gear. Not only are the microorganism counts higher due to warmer water, but many boats in the 40-foot-plus range spend a fair amount of time sitting in relatively static canals, the perfect environment for the growth of algae and barnacles. All these factors add up to bad performance.
The good news is that paint companies are addressing the problem. To get a handle on how one such company, Interlux, has enhanced its products to help combat everything from slime to barnacles, I spent a day at Norseman Shipbuilding, a Miami repair yard, with Interlux’s sales representative Joe Purtell. What I observed was how these new products are attacking one of the most intractable of all fouling challenges: running gear.
Painting is one of boaters’ favorite do it yourself projects, and had this been a deck-painting project, we could have left the yard out of the loop altogether. However, since preparation is so important where metal is concerned, we arranged to have the pros do the prep work and convinced the owner of our 41-foot Sea Ray to do the painting. Purtell explained our strategy this way: “Sandblasting creates the most uniform profile for optimum adhesion, and unless one feels quite proficient with a grinder, what with props being computer-balanced and all, I think letting the yard take the metal to bright is the best plan.”
One of the unique aspects of working with metal is that after you take it down, it almost instantly begins to oxidize. Any knowledgeable repair yard will keep this in mind, but if you decide to do the work yourself, you should immediately wipe down the area with the company’s 216 thinner (an exceptionally strong solvent formulated to dry rapidly) and apply one coat of 353/354 VinyLux Primewash—that is unless you want to essentially resand the entire project. The application is crucial. Unlike most underwater paints where thicker is better, this hard, self-etching primer must be put on thin enough that you can see through it, so reduce it by 25 percent with the proper Thinner. (Etching provides the chemical and physical bond for the primer; without it, the primer and paint will flake off.)
This article originally appeared in the March 2004 issue of Power & Motoryacht magazine.