I’m probably like a lot of do-it-yourself sailors when it comes to painting techniques: I’ve tried them all. And I’ve had varying degrees of success — from awful to “not bad” — with each. I think it’s the very nature of paint — i.e. the fact that it just doesn’t seem to like to stick to anything — that makes using it such a battle. Not to mention that even if it does stick, and even if you do get a good finish, it still doesn’t last very long.
But there’s hope: I’ve recently experienced a paint alternative called powder coating. I like it for two important reasons:
• The final finish is thick, durable, shiny, with an even distribution.
• It actually partners better with my tendencies to focus on mechanical things, and my general desire to avoid doing purely cosmetic things. With powder coating, all I have to do is take the pieces apart and get them off the boat (my mechanical side), after which I dump them in a box and drive them to the powder-coater (my lazy side). In a few days: magic. A whole new unit of whatever, ready for reassembly.
I most recently experienced this sort of satisfaction when my boat partners and I decided, once and for all, to tackle my nemesis: The head. The head has been painted many times, the last instance being five years ago when I coated it with a nice white lacquer finish that started to go green in just about a month, despite what I thought was adequate prep work and quality paint. No doubt this was exacerbated because the head is an oft-missed target while sailing offshore, but I’ve always thought that if you could tame the head, you could tame anything. So, I attacked the dragon in its lair, dragged it into the light of day, dismembered it, and brought its pieces to Dave Hoar, Portland, Maine’s local powder coating pro, at New England Fiberglass.
Technically, both painting and powder are “coatings,” the difference being that the former comes in liquid form (a solvent that contains the pigments and fillers in suspension), while the latter is applied as a dried powder that, once heated, allows the powder to flow out/together to create a (relatively thick) skin on the surface. Interestingly the basic materials are the same — powder coatings can be made of epoxy, polyurethanes, polyester — they are just mixed and produced differently; i.e., “dry,” without solvents.
Powder coating also has a couple of environmental advantages that paint doesn’t: it emits no volatile organic compounds (VOCs) and produces no hazardous waste — mainly because any overspray of the powder can be captured and reused.
As with any coating, the surface prep for powder coating is critical. Surface contaminants will affect how well the coating adheres, and how the final finish appears. More often than not, this is accomplished by some sort of abrasive blasting — sand, shot, plastic, etc. It can also be done with chemicals.
Once it is clean, places that should not be coated (i.e. threads, intake/exhaust ports, etc.) are carefully taped or plugged with foam. The powder is then sprayed on the material with an electrostatic gun; the positively-charged powder is shot through compressed air at the grounded object, which causes the powder to “stick” to the object. The next step is for all parts to go into the kiln for baking, after which they are removed, and hung up to cool and cure.
The results reveal parts that almost look as if they’ve been “dipped” in an epoxy coating. It is a tangibly thick, uniform finish that seems less prone to chipping — and certainly is far more attractive than any liquid coating I’ve ever applied.
I’m sure the environment in which the head lives will eventually take its toll on any kind of coating. Nonetheless, I’m feeling like I’ve postponed this bit of nasty, ongoing maintenance much further into the future than I was ever able to before — long live powder coating!