I have a 1978 Catalina 27. The boat is in great shape and I am working to upgrade the interior. I would like to get the gelcoat into good condition as well. I just took off all of the wood around my companionway and was shocked at the difference in the gelcoat under the wood vrs. the gelcoat exposed to the elements. Most articles I see deal with oxidation. I am not sure that's what I have. What I have seems to be a pitting of the surface and all of the pits are filled with dirt. I have heard that I need to sand or use rubbing compound. Here are my questions: How can I tell which I need? I have a rotary pollisher. Is this what I use to apply the rubbing compound? What type of head do I use? How do I know when its enough so that I avoid rubbing through, as in the trilogy? Will I be rubbing just to get the dirt out, or trying to get right to the bottom of all those pits? Sorry for all of the questions but I don't want to grind myself into $3-4000 for a new gelcoat. Any help is apreciated, Thanks, Keir Hood
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Barry
Gelcoat Restoration
You can't polish an old boat too much or you'll wear through the color coat. I'd clean it as best as I could and use Poli Glow. The new acrylic finishes actually fill in rough weathered textures that results in a great shine. You can't match the end result using any kind of wax. Check the archives. They have a website that describes this product. I used it on my 18 year old Hunter with good success. Barry
You can't polish an old boat too much or you'll wear through the color coat. I'd clean it as best as I could and use Poli Glow. The new acrylic finishes actually fill in rough weathered textures that results in a great shine. You can't match the end result using any kind of wax. Check the archives. They have a website that describes this product. I used it on my 18 year old Hunter with good success. Barry
Check out the Gelcoat forum .
Keir: Check out the Gelcoat forum on the website then you can decide which way you want to go. http://www.sailboatowners.com/forums/menu.tpl?fno=121
Keir: Check out the Gelcoat forum on the website then you can decide which way you want to go. http://www.sailboatowners.com/forums/menu.tpl?fno=121
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james rohr
I would'nt do too much compounding on a gel coat t
I have a 1979 O'day the gel coat is also oxadized. about ten yrs ago I stopped using all polishes that had any abrasive in them. To clean the stains out of the gel coat use Hull stain remover(oxalic acid) rinse well. then I put on 4or 5 coats of future acrilic floor wax. Yes i said J&J future floor wax. It holds up well and will keep any stains from penatrating the gel coat.In the spring I remove the previous years coats with ammonia in a spray bottle. this disolves the old wax,as your removing it rinse and you are ready to re wax. 4 or 5 coats are nesc to give a good look. when your finished it will look like brand new gel coat, at a fraction of the cost of the fancy marine acrilic names. On my 30 it takes me about 4hr to remove old and rewax. Don't tell nu glass or vert glass about this though. We'll just keep this our little secret. Be sure you allow enough time between coats or you will soften the prev coats and you'll start to get what look like little streaks in it. usually about 30min between coats. can be less if its a warm sunny day. you have to play it a little by ear as to the time. good luck. Capn J
I have a 1979 O'day the gel coat is also oxadized. about ten yrs ago I stopped using all polishes that had any abrasive in them. To clean the stains out of the gel coat use Hull stain remover(oxalic acid) rinse well. then I put on 4or 5 coats of future acrilic floor wax. Yes i said J&J future floor wax. It holds up well and will keep any stains from penatrating the gel coat.In the spring I remove the previous years coats with ammonia in a spray bottle. this disolves the old wax,as your removing it rinse and you are ready to re wax. 4 or 5 coats are nesc to give a good look. when your finished it will look like brand new gel coat, at a fraction of the cost of the fancy marine acrilic names. On my 30 it takes me about 4hr to remove old and rewax. Don't tell nu glass or vert glass about this though. We'll just keep this our little secret. Be sure you allow enough time between coats or you will soften the prev coats and you'll start to get what look like little streaks in it. usually about 30min between coats. can be less if its a warm sunny day. you have to play it a little by ear as to the time. good luck. Capn J
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Jim WIllis
Pits in gelcoat and how to fix them
I am very familiar with the pits you mention, having done many demos on pieces of boats, complete boats and my own boat over the years. I too, was quoted for a wet-sand/compound job that I didn't go for, thank god! The pits you mention, are actually the upper (wider end) of pores that form as oxidation penetrates the gelcoat, like rust in metal. As for the analogy with metal, you would have to sand/compound VERY deep to get to the bottom of them and would have little good gelcoat left. You have to be particularly careful on stripes where the stripe is very thin, beign applied over the original (thicker) layer of hull gelcoat. If you want to see more on this go to our website www.IslandgirlProducts.com/techinfo, then "how plastics break down". The pits are "full of dirt" becuase they contain (having been made by oxidation) chalk that acts like blotting paper to soak up dirt from air pollution etc. Some of the "dirt" may actually be mildew that feeds on teh broken down plastic dirt components. This is my advice (based upon what worked on my boat and from the input form hundreds of boat owners). 1. Do not use wet sanding unless the gelcoat surface is so rough that it feels really rough when you scrape your finger over the surface. If you do wet sand, do the minimum possible to take the worst of the roughness off. Use a very fine grit (600, then 1000). Alternatively I have found that the 3M "synthetic steel wool" scuff pads ("000" very fine) can be used on a wooden or hard rubber block with very light pressure. 2. If you are then going to use compound try a little first are first and ver VERY careful. I have seen gelcoat that is so porous that it soaks up the dye from the compound making the surface orange! In my view, the only time you should use compounding is to remove an outer layer of discolored gelcoat due to breakdown of the pigment (would NOT apply to white). A good example is removing a very thin superficial layer of red gelcoat that has gone "orange". 3. It is better to chemically remove the chalk and dirt. No water-based cleaner will do this and many solvents don't either. You have to use a glycol based cleaner. On white (that I think your boat is) Sea Glow Cleanser conditioner will remove deep-down oxidation, replace with clear conditioner anti-oxidants, mildew inhibitors etc, as well as strong fluorescing agents that "light up" the colors making the white snowy white again. 3. Now comes the contentious part - how to seal the surface. Liwuid wax is out (too thin), if the pits are not deep paste wax (we like collinite) will work, but it works best over a sealing coat of Silkenseal. Only problem with paste waxes is difficulty of applying and the slight yellowish color if put on too thick. This is partly due to carnuaba and partly due to the aminofunctional silicones (that makes wax detergent resistant). 4. Water-based acrylics, (New glass, Vertglass, poliglow etc asn yes, Future, Mop'nGlow etc) seal the surface but to seal the surface to smoothness, you have to fill in those pore - many coats. Nice results can be seen on dark-colored gelcoat and to make sure there is no peeling prepare the surface very well. However, on white gelcoat, water based acrylics have a reputation for yellowing (can even happen with solvent based clear-coats) ask for a written warranty! 5. My boat. The white. cap rail was very pitted. They are all filled in by about 3 coats of variou incarnations of our Simply Brilliant Superwax. I made all the errors of putting on too much at a time etc, but finally found that applying over a sealing coat of Silkenseal made it less able to soak in and gave greater gloss. Yellowing has not occurred. and this year I am sealing the whole surface with our newer "all resin" superglaze product. After a tropical year, only the dark green stripe has shown return of dullness. PREVENTION IS BETTER THAN CURE. Gelcoat can last without chalking and pitting if it is well looked after from new. In my view the most essential thing is avoiding use of abrasives from the get go. The surface area is made greater (for oxidation to start to penetrate) and the original silicone resins of the mold release are removed unecessarily. That is why somethine like a non-acrylic clear coat is a good idea. Hope this was not too overbearing and boring but that's me! Jim W
I am very familiar with the pits you mention, having done many demos on pieces of boats, complete boats and my own boat over the years. I too, was quoted for a wet-sand/compound job that I didn't go for, thank god! The pits you mention, are actually the upper (wider end) of pores that form as oxidation penetrates the gelcoat, like rust in metal. As for the analogy with metal, you would have to sand/compound VERY deep to get to the bottom of them and would have little good gelcoat left. You have to be particularly careful on stripes where the stripe is very thin, beign applied over the original (thicker) layer of hull gelcoat. If you want to see more on this go to our website www.IslandgirlProducts.com/techinfo, then "how plastics break down". The pits are "full of dirt" becuase they contain (having been made by oxidation) chalk that acts like blotting paper to soak up dirt from air pollution etc. Some of the "dirt" may actually be mildew that feeds on teh broken down plastic dirt components. This is my advice (based upon what worked on my boat and from the input form hundreds of boat owners). 1. Do not use wet sanding unless the gelcoat surface is so rough that it feels really rough when you scrape your finger over the surface. If you do wet sand, do the minimum possible to take the worst of the roughness off. Use a very fine grit (600, then 1000). Alternatively I have found that the 3M "synthetic steel wool" scuff pads ("000" very fine) can be used on a wooden or hard rubber block with very light pressure. 2. If you are then going to use compound try a little first are first and ver VERY careful. I have seen gelcoat that is so porous that it soaks up the dye from the compound making the surface orange! In my view, the only time you should use compounding is to remove an outer layer of discolored gelcoat due to breakdown of the pigment (would NOT apply to white). A good example is removing a very thin superficial layer of red gelcoat that has gone "orange". 3. It is better to chemically remove the chalk and dirt. No water-based cleaner will do this and many solvents don't either. You have to use a glycol based cleaner. On white (that I think your boat is) Sea Glow Cleanser conditioner will remove deep-down oxidation, replace with clear conditioner anti-oxidants, mildew inhibitors etc, as well as strong fluorescing agents that "light up" the colors making the white snowy white again. 3. Now comes the contentious part - how to seal the surface. Liwuid wax is out (too thin), if the pits are not deep paste wax (we like collinite) will work, but it works best over a sealing coat of Silkenseal. Only problem with paste waxes is difficulty of applying and the slight yellowish color if put on too thick. This is partly due to carnuaba and partly due to the aminofunctional silicones (that makes wax detergent resistant). 4. Water-based acrylics, (New glass, Vertglass, poliglow etc asn yes, Future, Mop'nGlow etc) seal the surface but to seal the surface to smoothness, you have to fill in those pore - many coats. Nice results can be seen on dark-colored gelcoat and to make sure there is no peeling prepare the surface very well. However, on white gelcoat, water based acrylics have a reputation for yellowing (can even happen with solvent based clear-coats) ask for a written warranty! 5. My boat. The white. cap rail was very pitted. They are all filled in by about 3 coats of variou incarnations of our Simply Brilliant Superwax. I made all the errors of putting on too much at a time etc, but finally found that applying over a sealing coat of Silkenseal made it less able to soak in and gave greater gloss. Yellowing has not occurred. and this year I am sealing the whole surface with our newer "all resin" superglaze product. After a tropical year, only the dark green stripe has shown return of dullness. PREVENTION IS BETTER THAN CURE. Gelcoat can last without chalking and pitting if it is well looked after from new. In my view the most essential thing is avoiding use of abrasives from the get go. The surface area is made greater (for oxidation to start to penetrate) and the original silicone resins of the mold release are removed unecessarily. That is why somethine like a non-acrylic clear coat is a good idea. Hope this was not too overbearing and boring but that's me! Jim W
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