Each spring certain tasks need to be done to comission your boat. Painting the bottom is a common one. This article covers applying Interlux’s VC 17 anti fouling paint.

VC 17 is always available at special prices in our ships store and online at shop.torresen.com

Applying VC 17 Bottom Paint

VC-17 is one of the easiest antifouling paints to apply, and to maintain. But like any other antifouling system, there are some things that have to be done both at the initial application and as part of an annual maintenance program. There are three basic application situations that will be encountered. I’ll take them one at a time.

First is the new application. This means applying VC-17 to a new boat or a boat that has recently had a different antifouling system on it that has been removed. Essentially a clean fiberglass hull. If it’s a new hull, it must be dewaxed completely to remove any residual mold release wax. This should be done with the Interlux 202 Solvent Wash. We recommend using a two-rag system. One to put the solvent on the hull, another to wipe it clean. Change both rags frequently and remember not to dip the application rag back into the solvent container, thereby contaminating it.

When you’re done with the entire hull, take a hose or container of water and wet down portions of the hull. If the water beads up, there’s still wax on the hull and the process must be repeated. Failure to remove the wax can prevent the paint adhering to the hull. Also please note, this must be done before sanding the hull so as not to imbed the wax in the gelcoat during the sanding process.

When you are sure you’ve removed all the wax from the hull, the next step is to sand the entire surface to be painted with VC-17. This is a must. You must abrade the hull to provide a profile for the paint to stick to. Failure to do so can result in the paint detaching from the hull. The hull should be sanded with 180-grit sandpaper, 220 at the finest.

After sanding wipe the hull down with 202 Solvent Wash again to remove sanding residue. Some boat manufacturers aren’t in favor of sanding hulls because they feel this may increase the likelihood of osmotic blistering. I know of no evidence to support this, but it is the manufacturers warranty. In this case there has been some success reported using a coarse Scotch Brite Pad to scrub the hull. This can be done with the 202 Solvent wash. You must be sure to leave a visible scratch in the gelcoat. I’d have to say that I feel this would provide minimal adhesion at best and I can’t recommend the system even though I know it’s done.

After cleaning and abrading the surface, you’re ready to apply the paint. Pick a day that isn’t raining, and is above 50 degrees F. You’ll notice that under the hat on the VC-17 can there is a bag of copper. This must be mixed into the paint. Please be careful doing this as the copper is very fine and will fly around. (Perhaps a good time for a paper sanding mask) This is what provides the antifouling. You’ll notice the can is short filled to allow you to add the copper and stir it in without spilling. This does NOT mean that the can should be filled with a solvent. This is not the case. Only in rare cases should any antifouling paint be thinned and in the case of VC-17, almost never.

The paint is best applied with a roller or by spray, IF the yard you’re in allows spraying. Please check with the yard manager about this. If you can and do choose to spray, contact your Interlux representative for details. If you’re going to roll, any solvent resistant foam or short nap roller cover will work.
The recommended system is to start from the bottom of the hull or keel, and roll upwards. Do not over roll or attempt to “smooth” the paint out. It’s self-leveling and will do that itself. Just make one pass up to the waterline tape then start over at the bottom. Keep the roller well filled with paint, but not to the point that it runs off onto the ground, or your arm.

A word of caution, This paint dries very quickly. Do not pour the entire can into the tray. It will evaporate. Pour in just enough to fill the roller, then add more to the tray when you need to refill the roller. Work your way around the boat working back to the place you started. During an initial application, ALWAYS apply two coats. The second coat can be applied after the first coat has dried, about a half an hour under most conditions. Remove the tape and the boat can be launched about a
half-hour after painting.

Second application type - you already have VC-17 on the boat. Reapplication is one of the joys of this product. Assuming the boat was pressure washed and stored relatively clean, all that is required is to wipe the hull down with a damp rag to remove any dust or particles that may be on the hull. Inspect the bottom to insure there are no abrasions or flaking spots. If there are, these can and should be touched up lightly with 180 grit on a sanding pad. Just feather in the affected area, wipe to remove any dust and repaint. There is no need to sand the entire hull, in fact, it’s not recommended. If you do, there is a danger of sanding through, which would require applying two coats again. Applying the paint is the same as above described procedure and once again, the boat can be launched in about one half-hour. That’s all there is to it!

The third instance. Applying VC-17 over an epoxy barrier coat. It is not true, by the way, that VC-17 can only be applied over VC Tar. While it certainly can be, it goes on over Interprotect Epoxy barrier coats just as well. In this case apply the barrier coat according to the instructions. After applying the last coat of tar or epoxy, follow the instruction for applying the first coat of antifouling without sanding (called “hot” or “wet on wet” coating) in the case of VC Tar or Interprotect 2000E/2001E. In the case of Interprotect 3000/3001, you must let the epoxy harden and sand with 180 just as though it were a new hull. Please be sure you’re reading the correct times for applying antifouling paints (not another coat of epoxy, they’re different). The second coat of VC-17 can be applied when the first has dried, again, about a half an hour. Words of caution here, If you have just applied a barrier coat, please do not launch the boat in a half-hour. Please allow the epoxy to cure for as long as possible before launching. (A week perhaps.) This is especially important in the case of VC Tar as this product takes a long time to cure and lifting the boat too soon can cause the straps to distort the tar at lifting points. Maintenance after this is just the same as described above. And that’s all there is to it. While it doesn’t achieve the boating Nirvana we all look for, the bottom that never has to be worked on, it does come about as close as chemistry will allow us in this day and age. For any questions, Contact Torresen Marine or visit us online at shop.torresen.com

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