I'm getting ready to remove the very old, thin, and worn out antifouling on my beneteau F235. I've researched the various ways of getting the antifouling off (none appear to be particularly pleasant!), and have almost decided on the Peel Away product. I emailed the makers and learned that 'Peel Away 1' is sold through paint stores, and is identical to the 'Peel Away Marine Strip II' product that they sell through marine stores (but not mine!). This stuff is recommended (acc to their webpage) if one wants to preserve a barrier coat that is on some hulls underneath the antifouling. They said that 'Peel Away 7' (from paint stores) is the same as 'Peel Away Marine Strip I' (from marine stores), which appears to be harsher than Strip II with regard to barrier coats. Now for my question ... Do I actually have a barrier coat?? I don't have any idea what a barrier coat is, whether or not one was ever applied to my hull (1989 model year), or even what to look for if I want to try to determine this myself. Does anyone know if (Beneteau) hulls of this vintage mostly had, or did not have barrier coats? Alternatively, how can I inspect my hull to find out if I have on or not. The Peel Away products are rather pricey, so for that reason, and not wanting to screw up my hull, I should find out before lashing out and getting Peel Away 1 or 7. Thanks, Nei
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RE: Barrier coat
All bottom paints allow water to penetrate them and expose the hull to a constant water exposure. Barrier coats prevent water from passing through them and so prevent the possible formation of blisters. To find out if you have a barrier coat, simply sand away a small test area and watch for a color change from your bottom paint to a gray color before you reach gelcoat. If you don't see the color change before you get to gel then you have no barrier coat.
All bottom paints allow water to penetrate them and expose the hull to a constant water exposure. Barrier coats prevent water from passing through them and so prevent the possible formation of blisters. To find out if you have a barrier coat, simply sand away a small test area and watch for a color change from your bottom paint to a gray color before you reach gelcoat. If you don't see the color change before you get to gel then you have no barrier coat.
Why strip the old paint?
Hello Neil, First things first. If this is your first bottom job, take a breath and relax. Most boat yards and do-it-yourselfers just sand the bottom, mask the bootstripe, and paint the bottom with anti-foulent paint. I was at a yard once in Madisonville, La that had a slurry. Basically a high pressure water hose with an atachment to suck up blasting sand with the water. NO SANDING!! Tape and paint Baby! Worst case is you'll need to sand it(rough it up)before you paint. Unless the paint is really thick and unsightly along the bootstripe I would leave it alone. The barrier coat is a replacement to the gelcoat and perhaps a little deeper that would have been put on by a previous owner because of blisters.If you have a barrier coat you should be able to tell by removing paint below the bootstripe. It will not match the gelcoat. You should be able to see where they ground out or machined out the old gelcoat. By the way, the last Catalina 30 I almost bought had a barrier coat. AND BLISTERS! Please research blisters before applying a barrier coat. Take my $2500.00 bottom job as a lesson! There is a lot more known now than in 1995. Good Luck
Hello Neil, First things first. If this is your first bottom job, take a breath and relax. Most boat yards and do-it-yourselfers just sand the bottom, mask the bootstripe, and paint the bottom with anti-foulent paint. I was at a yard once in Madisonville, La that had a slurry. Basically a high pressure water hose with an atachment to suck up blasting sand with the water. NO SANDING!! Tape and paint Baby! Worst case is you'll need to sand it(rough it up)before you paint. Unless the paint is really thick and unsightly along the bootstripe I would leave it alone. The barrier coat is a replacement to the gelcoat and perhaps a little deeper that would have been put on by a previous owner because of blisters.If you have a barrier coat you should be able to tell by removing paint below the bootstripe. It will not match the gelcoat. You should be able to see where they ground out or machined out the old gelcoat. By the way, the last Catalina 30 I almost bought had a barrier coat. AND BLISTERS! Please research blisters before applying a barrier coat. Take my $2500.00 bottom job as a lesson! There is a lot more known now than in 1995. Good Luck
I can't help chiming in,,
The 'LOT MORE' is keep your bilge dry. If that is possible with your boat, dry her out and paint the INSIDE. Any good marine paint will work. The idea is to keep standing water from wicking along the fibers. Shhhh, this is our secret. If the barrier coat companies find out they'll flame me.
The 'LOT MORE' is keep your bilge dry. If that is possible with your boat, dry her out and paint the INSIDE. Any good marine paint will work. The idea is to keep standing water from wicking along the fibers. Shhhh, this is our secret. If the barrier coat companies find out they'll flame me.
More grist for the mill. . .
I have used the Peel Away product. It is a bit awkward , but seemed to work pretty well. I believe that I had about 6+ coats of bottom paint on at the time. Normally you can do a quick sand and paint as the other posts have mentioned. Over time you reach a point where it all has to come off and start from bare hull again. Barrier coat is just as the name implies, a coating that provides a barrier against water penetration. You see, fiberglass can actually absorb some amount of water. Nothing good happens once water gets into the fiberglass. Barrier coats are epoxy-based. Epoxy is much more water resistant that fiberglass, so it is used as a "barrier". If you go to the trouble of taking the bottom paint off, do yourself the favor of applying a barrier coat (at and below the waterline). It can only help. Regards, Ted
I have used the Peel Away product. It is a bit awkward , but seemed to work pretty well. I believe that I had about 6+ coats of bottom paint on at the time. Normally you can do a quick sand and paint as the other posts have mentioned. Over time you reach a point where it all has to come off and start from bare hull again. Barrier coat is just as the name implies, a coating that provides a barrier against water penetration. You see, fiberglass can actually absorb some amount of water. Nothing good happens once water gets into the fiberglass. Barrier coats are epoxy-based. Epoxy is much more water resistant that fiberglass, so it is used as a "barrier". If you go to the trouble of taking the bottom paint off, do yourself the favor of applying a barrier coat (at and below the waterline). It can only help. Regards, Ted
Just to clear up a few things already mentioned
A barrier coat doesn't have to just be grey in colour. Interlux's Interprotect 2000 for example is grey but their VC Tar is black. And if West System epoxy was used it would be a honey coloured transparent look. Just look for something that is different than the bottom paint and the gelcoat. Regarding the gelcoat, it is the gelcoat that is porous and can let water through into the fiberglass and resin laminate. Some owners applied the barrier coat over perfectly good gelcoat as a precaution against blistering (osmosis) while in cases where there was a lot of blister damage the gelcoat may have been removed and replaced with epoxy barrier coat over the laminate. Kevin
A barrier coat doesn't have to just be grey in colour. Interlux's Interprotect 2000 for example is grey but their VC Tar is black. And if West System epoxy was used it would be a honey coloured transparent look. Just look for something that is different than the bottom paint and the gelcoat. Regarding the gelcoat, it is the gelcoat that is porous and can let water through into the fiberglass and resin laminate. Some owners applied the barrier coat over perfectly good gelcoat as a precaution against blistering (osmosis) while in cases where there was a lot of blister damage the gelcoat may have been removed and replaced with epoxy barrier coat over the laminate. Kevin
Barrier Coats
If you hand scrape the existing bottom paint with a Red Devil scraper you will either find barrier coats or the gel coat. If you don't have any blisters you shouldn't need to add barrier coats. If you do have blisters you could hand scrape, go through the drying out process, fill them, sand with 60 grit wet or dry paper, and apply multiple coats of Interlux 2000 before re-doing the bottom paint. Assuming your existing bottom paint is ablative it will scrape off relatively easily. The stripper products are more likely to be effective on epoxy or vinyls but could be hazardous depending upon the solvents used. Again, if you don't have blisters you can save yourslf a lot of time and trouble with 'touch-up' sanding and a new application of compatible bottom paint. If you want to switch to a particular bottom paint which is not compatible with the existing paint, you may need to scrape it, sand it and solvent wash with Acetone before applying the new bottom paint.
If you hand scrape the existing bottom paint with a Red Devil scraper you will either find barrier coats or the gel coat. If you don't have any blisters you shouldn't need to add barrier coats. If you do have blisters you could hand scrape, go through the drying out process, fill them, sand with 60 grit wet or dry paper, and apply multiple coats of Interlux 2000 before re-doing the bottom paint. Assuming your existing bottom paint is ablative it will scrape off relatively easily. The stripper products are more likely to be effective on epoxy or vinyls but could be hazardous depending upon the solvents used. Again, if you don't have blisters you can save yourslf a lot of time and trouble with 'touch-up' sanding and a new application of compatible bottom paint. If you want to switch to a particular bottom paint which is not compatible with the existing paint, you may need to scrape it, sand it and solvent wash with Acetone before applying the new bottom paint.
barrier coat and blisters
barrier coat is to prevent blisters. links to read: http://www.sailnet.com/collections/articles/index.cfm?articleid=caseyd0036 http://www.sailnet.com/collections/articles/index.cfm?articleid=caseyd027 also the west system 'how to on blister/barriecoat' prevent blister in first place... -search articles on sailnet 'blisters'
barrier coat is to prevent blisters. links to read: http://www.sailnet.com/collections/articles/index.cfm?articleid=caseyd0036 http://www.sailnet.com/collections/articles/index.cfm?articleid=caseyd027 also the west system 'how to on blister/barriecoat' prevent blister in first place... -search articles on sailnet 'blisters'
Agree with Kevin
CopperPoxy which he didn't mention is a coppery gold color. Interprotect is grey, often has a bumpy rough surface when a roller is used, and leaves a little ridge near the waterline where the extra thickness ends. West epoxy is honey colored, is easy to scrape paint off and is sometimes wavy because it tends to sag. You may also run into a different color layer of paint, which is often used to warn you when you are down to the last layer before the gel or barrier coat. Don't be confused by it. Sometimes the gel coat is removed when there are lots of blisters. If there weren't many, the barrier coat goes onto the gelcoat. Some people don't wait for blisters but do a barrier coat like undercoating on a car. Be very careful with sandblasting. It usually pits the surface and makes thing worse. Only use experienced professionals if you use this. Don't sand or sandblast a barrier coat if its there, it depends on a minimum thickness to succeed.
CopperPoxy which he didn't mention is a coppery gold color. Interprotect is grey, often has a bumpy rough surface when a roller is used, and leaves a little ridge near the waterline where the extra thickness ends. West epoxy is honey colored, is easy to scrape paint off and is sometimes wavy because it tends to sag. You may also run into a different color layer of paint, which is often used to warn you when you are down to the last layer before the gel or barrier coat. Don't be confused by it. Sometimes the gel coat is removed when there are lots of blisters. If there weren't many, the barrier coat goes onto the gelcoat. Some people don't wait for blisters but do a barrier coat like undercoating on a car. Be very careful with sandblasting. It usually pits the surface and makes thing worse. Only use experienced professionals if you use this. Don't sand or sandblast a barrier coat if its there, it depends on a minimum thickness to succeed.
many thanks
I do have blisters - about 7 or 8 largish blisters about 3-4" in diameter each! Last weekend, I removed the hard 'skin' over the bulged areas (=the gel coat?) to expose the wet, mat-like fiberglass material. Next, I plan to carefully sand out the wet fiberglass, and let these areas dry out over the winter before refilling the blistered areas with new fiberglass. The boat had been in the water (inland lake in NC) continuously for at least three years before I bought it this summer. The antifouling is worn off in many places (exposing a dull reddish/purplish layer - perhaps a barrier coat?) in places and just plain crappy in other areas. Also, I have the joy of owning an iron keel that has lots of warty-looking rust bumps. Ultimately, I want a really nice, smooth bottom, that is a protected as possible against new blisters forming, and a keel that is sufficiently coated to reduce (if not actually prevent) the incidence of more rust forming. I'd like Santa to provide all this, but I don't think I've been good enough this year to hope for that to happen. Question: given that my blisters are now 'open', is there any reason(s) not to proceed with the antifouling removal and keel clean up work while I have the time, as long as I keep the paint removal compounds and other liquids out of the open blister areas? Maybe I can even do the bulk of the barrier coat and antifouling reapplication work this side of winter, and just finish that job off in the spring after I fill the blister holes?
I do have blisters - about 7 or 8 largish blisters about 3-4" in diameter each! Last weekend, I removed the hard 'skin' over the bulged areas (=the gel coat?) to expose the wet, mat-like fiberglass material. Next, I plan to carefully sand out the wet fiberglass, and let these areas dry out over the winter before refilling the blistered areas with new fiberglass. The boat had been in the water (inland lake in NC) continuously for at least three years before I bought it this summer. The antifouling is worn off in many places (exposing a dull reddish/purplish layer - perhaps a barrier coat?) in places and just plain crappy in other areas. Also, I have the joy of owning an iron keel that has lots of warty-looking rust bumps. Ultimately, I want a really nice, smooth bottom, that is a protected as possible against new blisters forming, and a keel that is sufficiently coated to reduce (if not actually prevent) the incidence of more rust forming. I'd like Santa to provide all this, but I don't think I've been good enough this year to hope for that to happen. Question: given that my blisters are now 'open', is there any reason(s) not to proceed with the antifouling removal and keel clean up work while I have the time, as long as I keep the paint removal compounds and other liquids out of the open blister areas? Maybe I can even do the bulk of the barrier coat and antifouling reapplication work this side of winter, and just finish that job off in the spring after I fill the blister holes?
What I did.
To take off the anti-fouling I used two paint scrapers with the sharp corners ground off. One wide one for large flat areas and a narrow one for tight spots. I finished with 80 grit but would recommend a rented vacuum sander. You should stop when most of the bottom is a mottled white gelcoat. If you try to get a clean white you might take off gelcoat. You do not want to do that. I did this on a 37-footer. I had a few pencil eraser size blisters(?). They were not open and not wet but I still dremeled and filled. After a good cleaning with the Interlux recommended chemical I put on five coats of Interlux 2000E. The problem here is timing. Each coat has to follow the next within a certain number of hours since you are working with an epoxy. If a coat drys too much the next coat will not adhere as well. I would suggest waiting for a spell of warm weather, at least 48 consecutive hours. I ended up working with spotlights! Do this after the blisters have been filled and faired. You want a solid epoxy bottom, not one with "spots".
To take off the anti-fouling I used two paint scrapers with the sharp corners ground off. One wide one for large flat areas and a narrow one for tight spots. I finished with 80 grit but would recommend a rented vacuum sander. You should stop when most of the bottom is a mottled white gelcoat. If you try to get a clean white you might take off gelcoat. You do not want to do that. I did this on a 37-footer. I had a few pencil eraser size blisters(?). They were not open and not wet but I still dremeled and filled. After a good cleaning with the Interlux recommended chemical I put on five coats of Interlux 2000E. The problem here is timing. Each coat has to follow the next within a certain number of hours since you are working with an epoxy. If a coat drys too much the next coat will not adhere as well. I would suggest waiting for a spell of warm weather, at least 48 consecutive hours. I ended up working with spotlights! Do this after the blisters have been filled and faired. You want a solid epoxy bottom, not one with "spots".
while on the subject
how long can a boat be laid up before the anti-fouling paint loses it's anti-fouling properties? I have had several conflicting answers from a few days to a few weeks. I had a new bottom job back in May and my boat is laid up about three weeks for some minor repairs.
how long can a boat be laid up before the anti-fouling paint loses it's anti-fouling properties? I have had several conflicting answers from a few days to a few weeks. I had a new bottom job back in May and my boat is laid up about three weeks for some minor repairs.
ablative paint stays good
indefinately. But the harder expoxy co-polymers need to go back in the water in a few weeks. Dan I would assume that you have ablative type of paint. With my trailerable sailboat I would get everything ready for painting then paint the weekend before launching. The West advisor talks about this. Dan of Navarre what happened to your boat??
indefinately. But the harder expoxy co-polymers need to go back in the water in a few weeks. Dan I would assume that you have ablative type of paint. With my trailerable sailboat I would get everything ready for painting then paint the weekend before launching. The West advisor talks about this. Dan of Navarre what happened to your boat??
One more chime
My source about the cause of blisters is a 'news release' printed in either Cruising World or Sail, about ten years ago. The story was of a Midwest university (the name escapes me) that did a study of blisters. The story mentioned that 85% of all hull blisters are caused by standing water in the bilge, not the water the boat sits in. That certainly is in keeping with my experience. Does anyone remember the article and/or the university that released their study.
My source about the cause of blisters is a 'news release' printed in either Cruising World or Sail, about ten years ago. The story was of a Midwest university (the name escapes me) that did a study of blisters. The story mentioned that 85% of all hull blisters are caused by standing water in the bilge, not the water the boat sits in. That certainly is in keeping with my experience. Does anyone remember the article and/or the university that released their study.
Tom, she broke
a mooring line during one of the "little squalls" that blew in from the Gulf and ending up with her rudder getting pounded on a concrete boat launch. I was very surprised to learn that the only damage was a beat up rudder. while she is on the hard at the insurance company expense I decided to go ahead and replace the standing rigging and to do some other "goodies" I have been wanting to do. hope we get her back in the water for the anual New Year's Day sail. a big power boat happened to be on the dock that night. he told me that he had run his engines almost all night to take some of the pressure off his dock lines. we recorded steady 35 gusting to 50 that night.
a mooring line during one of the "little squalls" that blew in from the Gulf and ending up with her rudder getting pounded on a concrete boat launch. I was very surprised to learn that the only damage was a beat up rudder. while she is on the hard at the insurance company expense I decided to go ahead and replace the standing rigging and to do some other "goodies" I have been wanting to do. hope we get her back in the water for the anual New Year's Day sail. a big power boat happened to be on the dock that night. he told me that he had run his engines almost all night to take some of the pressure off his dock lines. we recorded steady 35 gusting to 50 that night.
Neil, the key is to have a dry hull
before you apply the barrier coat, otherwise you just trap the moisture again. I'm with Fred on the issue of moisture seeping into the glass from the bilge, so you should paint your bilges if you have any doubt about them being sealed. On the paint stripping issue, I tried scraping, then sanding with orbital sander connected to a shop vac. Progress was too slow on a 37 foot hull. I then went to generic hardware paint sripper, which I had to apply in two coats to get through all the paint buildup. The only issues I found with stripper is that if left on too long it can start to melt/eat the gel coat. But since you are going to apply a barrier coat, I would not be concerned about this last issue. When I got down to gel coat there were no blisters. I had to remove the old bottom paint because it looked like allegator skin becuase incompatible paints had been applied. Once all paint was off I had the yard use a moisture meter on the hull with the result being that I should hold off for about a week for more drying ( I forget the moisture level found). I didn't want to wait, so I just applied an albative ( wear off) bottom paint, to avoid buildup, in the event I ever needed to restrip to apply a barrier. If you go with stripper, wear eye protection and get some good music for your Walkman.
before you apply the barrier coat, otherwise you just trap the moisture again. I'm with Fred on the issue of moisture seeping into the glass from the bilge, so you should paint your bilges if you have any doubt about them being sealed. On the paint stripping issue, I tried scraping, then sanding with orbital sander connected to a shop vac. Progress was too slow on a 37 foot hull. I then went to generic hardware paint sripper, which I had to apply in two coats to get through all the paint buildup. The only issues I found with stripper is that if left on too long it can start to melt/eat the gel coat. But since you are going to apply a barrier coat, I would not be concerned about this last issue. When I got down to gel coat there were no blisters. I had to remove the old bottom paint because it looked like allegator skin becuase incompatible paints had been applied. Once all paint was off I had the yard use a moisture meter on the hull with the result being that I should hold off for about a week for more drying ( I forget the moisture level found). I didn't want to wait, so I just applied an albative ( wear off) bottom paint, to avoid buildup, in the event I ever needed to restrip to apply a barrier. If you go with stripper, wear eye protection and get some good music for your Walkman.
That iron keel is going to be tricky
Neil, my make of boat also has a iron keel. When it comes to the type of work you need to do iron has one big disadvantage. As soon as you grind/sand down to bare metal its going to want to start rusting again if you leave it unprotected for more that 24 hrs. So you will have to plan your work so you can cover the bare areas the same day. I agree with Ed about applying the barrier coat after the bisters are filled and faired. Kevin
Neil, my make of boat also has a iron keel. When it comes to the type of work you need to do iron has one big disadvantage. As soon as you grind/sand down to bare metal its going to want to start rusting again if you leave it unprotected for more that 24 hrs. So you will have to plan your work so you can cover the bare areas the same day. I agree with Ed about applying the barrier coat after the bisters are filled and faired. Kevin
One more chime
Fred, your point makes sense. I have seen lots of boat mtce. articles which tell you to paint the bilges but without explaining why. Hopefully someone can dig up some additional info on the article you saw. Kevin
Fred, your point makes sense. I have seen lots of boat mtce. articles which tell you to paint the bilges but without explaining why. Hopefully someone can dig up some additional info on the article you saw. Kevin
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