Barrier paint on bottom

[Razor]

I have a 1983 Com-Pac 19. It does not have ablative bottom paint. I am assuming it has a barrier coat on it. Does the barrier coat have to be painted occasionally? Below are some pictures of where the paint on the keel is coming off/flaking off. Recommendations as to what the situation may be here and what I should do. I do keep her on a trailer but am considering keeping her in the water here in coastal NC (New Bern, NC).

Thanks!

[relamb]

Hard for me to tell from the pictures, but that looks more like scraping or gouging to me than paint flaking off.  Can you flake off more paint easily with your fingernail or a paint scraper around those areas, or is it basically solid?
Has another coat been painted over the areas that might have flaked off before?
Rick

[MacGyver]

It almost looks as if it is a epoxy paint, For instance, Interlux makes a racing finish that is Epoxy based, and is able to be sprayed for a smoother finish.
In the pictures, this paint looks like it could be that, but from the pictures it looks as if it might have had a poor prep work done to install it, causing it to delaminate from the boat bottom. That could be a number of things really, wrong grit used to prep, so bad mechanical connection, or it could be that the paint is losing its fight due to age, etc.

Any idea what the paint is exactly? So many products on the market......

If you dont know, I will tell you some tests you can perform (simple) to maybe help figure out what kind of paint it is.

Mac

[Razor]

Rick, It is possible the paint has been gouged or scrapped in loading the boat on the trailer against the keel guide. The keel guide does have carpet on it. I cannot remember running aground. I tried to flake it off with my fingernail but it did not flake off easily. 

Mac, I have had the boat for 2 years and it was the paint/finish that was on the boat when I purchased it. I have no idea what the paint is. What tests can be performed to determine the paint type?

Thanks!

Terry

[brackish]

appears to me to be gouges or scratches in barrier coat.  To answer your specific question if it is a barrier coat, and I think it is based on the high build nature, it should not need to be recoated.  I think all barrier coats are epoxy based, consequently I would repair it with an epoxy fairing compound which should be compatible.  Mix your own or use something like Marine Tex available in small amounts priced reasonably.  If you're not concerned with what it looks like at the repair areas, no additional coating should be necessary

Can you go back to the previous owner to verify the coating used?

I'm somewhat surprised that one would go to the expense of a barrier coat and then not use an anti fouling of some sort.  If the boat didn't stay in the water the barrier coat is not really necessary, if it did or does, the antifouling would be important.

[relamb]

Here's a link to the thread describing my bottom paint project, which has a link to pictures.
http://cpyoa.geekworkshosting.com/forum/index.php?topic=8010.msg58907#msg58907
That finish looks a little lighter gray than the Interlux Interprotect 2000e expoxy barrier coat that I used.

If you can't figure out what it is, I would try scraping off anything loose with a paint scraper.
Then fill /fair the gouges and scraped spots with Marine Tex, making them smooth with the rest of the bottom.
Get a quart of Interprotect 2000e and apply it to the areas where you have sanded/faired.
Finally, lightly sand the whole thing and paint it with whatever antifouling you want.  I've used an ablative on all three of my compacs.

I think the key though, is to make sure whatever is there is not flaking more.  It appears to me it's just scratches, and maybe somebody painted over them.  If you can't get much more scraped off, that's probably the case.
If it is flaking, you could either sand it all off, or just use an ablative paint over the whole bottom and whenever some flaked off, just reapply in that spot.
My two cents!
Rick

[MacGyver]

OLD PAINTS, the test I use:
When the paint is dry, rub your hand across it, If you get a heavy chaulky-ness on you hand it can mean that it is a ablative paint especially if it is more the color of the paint than a white chalk.

With a rub of the hand, not much will come off on your hand, maybe a light dusting on your hand, if anything, and that means it is a epoxy paint.

a wipe with a light amount of color, could mean it is a vinyl based paint, or basically not a ablative.

When you take a stiff brush to it, and if a lot of color comes off, then it is a Ablative. Not much color would be a non ablative paint, no color and it is a epoxy or hard possibly cured paint.

To repair most if not all of these, I will have my guys sand it all and fair out the loose stuff. then coat the entire boat with the same, or switch. Sometimes (we have had it happen a couple times over the years) you will paint it and the drying process will put the underlying paint under tension, which will cause it to let go of the substrate (the boat)

With what I see in the pictures, I am thinking that is Epoxy based, and possibly has been sprayed on, or burnished nicely. The product that comes to mind is VC Performance Epoxy. I have even seen a customers home job come off like what you are seeing, due to improper prep work.
To repair that, you would sand out the spots, I have used 80 or 100 or 120. fair it out so it is smooth. Run 2 or 3 coats on all the bare spots to help equalize them with the previously painted height, then follow up with a coat over the whole bottom for looks.

Just my thoughts. I have done 3 boats with that stuff, so I haven't seen it often, but when I have it was in person, so the pictures although good, kinda require you to add salt to my response, as I am not seeing it first hand.

Mac

[mac2compac]

With the season bearing down, we are planning on removing the old bottom paint from our 1984 compac 19. We have only had the boat for one full season so not sure of previous bottom paints/barrier. The boat has spent most of the recent past in the Hudson River over the sailing season. I took a hook scraper to the bottom and it seems that i am getting down to the gel coat without much effort. The scraped area is white in color. When i run my fingernail down the side of the boat from above the waterline down to where i have scraped i am looking for an edge to indicate where the barrier coat is but there is no edge. Is it possible their is no barrier coat? Would it be that easy to scrape off the barrier coat?
Thanks, Rich

[Salty19]

Rich, it's so hard to tell what any one boat has or has not been painted with, or if an epoxy coating was applied, but if you are easily hook scraping an old coating off to reveal smooth gelcoat, I would consider that a gift from high above!

With that said, it might be very poor paint, or might be good stuff that was not applied correctly and is coming off easily.  You'll probably never know, but darn if you're not lucky.

Better play it safe and be generous with offerings to Neptune next time you're out...

Jus sayin'