Proper Application of Anti-Fouling Paint

[BubbleHeadMd]

When we pulled our patrol boats in the UAE for a scrape and paint, We painted the bottoms with brushes. They were of all aluminum construction. The paint was functional, but needless to say, it wasn't very aesthetic. The goal was to get the boats back into service as rapidly as possilble.

So what's the best way to apply bottom paint when the boat's on the hard? Spray? Roller? How do you get an even coat without nap marks from the nap of the roller?

I have a 25 gal. air compressor and a spray gun. Do the typical anti-foul paints require reduction with a thinner or something?

Thanks

[David M]

You can apply bottom paint with all three methods. Spraying comes out the smoothest. Using a roller with a shallow nap comes out pretty decent. Brushing on of course is the crudest method but is fine for small places that need a touchup....like where the support pads were. Brush parallel to the water flow.

I would not get too picky about how smooth the bottom paint comes out unless you are racing. We are only talking a few one hundredths of a knot difference between a spray job or a good job with a roller. I have seen people go back and wet sand the finish coat to knock down the high spots but I think that is a little obsessive. What can I say, they were racers.

As far as reducing (thinning) goes, check the label on the can. If you can reduce the paint at all, it must be done using the manufacturers specified reducer. If the label does not have enough information then call the manufacturers help number.

[BubbleHeadMd]

Thanks for that.

I was only concerned about smoothness and brushlines for aeathetic's sake, and durability of the coating. I realize it's below the waterline and won't be seen much but...

[Ram]

Originally Posted by BubbleHeadMd

Thanks for that.

I was only concerned about smoothness and brushlines for aeathetic's sake, and durability of the coating. I realize it's below the waterline and won't be seen much but...

Wont be seen much?? only the fish are going to be able to see it , and they are not going to care!

[David M]

Only a very smart fish would care about the aesthetics...and dolphins can't talk. Yeah ok, I know dolphins are not fish before I hear from that crowd.

[fstbttms]

Originally Posted by BubbleHeadMd

I have a 25 gal. air compressor and a spray gun. Do the typical anti-foul paints require reduction with a thinner or something?

More important is the likelyhood that your yard will not allow you to apply the paint with a sprayer yourself. Best to check before going forward. Consider also that spraying the paint on uses a lot more product than other methods.