The bottom is all stripped. Whew! The paint was zipping off in places so I'll use 202 to dewax. The gelcoat seemed not to have been sanded before. It's smooth with a nice shine. THE QUESTION - how much sanding is enough. Don Casey says "lightly sand". Interlux says "sand with 80 grit". Others say 'scuffed up", ect...Does ALL of the gloss have to be sanded away? Will light sanding with just some scuffed up marks be OK? Thanks in advance!
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YOU DON'T NEED TO
SAND ANY MORE! Your done sanding. You need to expoxy and bottom paint. After all that sanding you better expoxy, 5 coats, before you bottom paint!
SAND ANY MORE! Your done sanding. You need to expoxy and bottom paint. After all that sanding you better expoxy, 5 coats, before you bottom paint!
Jim, it sounds to me that Rob was doing a chemical
strip. I understand him to say his gelcoat is still shinny. If so Rob, just scuff it up. No shine.
strip. I understand him to say his gelcoat is still shinny. If so Rob, just scuff it up. No shine.
Sand with the 80 grit
I just stripped my bottom. Interlux says sand with 80 grit before applying a barrier coat. Also if you wait to long they say resand with 80 grit. I would follow the directions. You don't need to go down to the fiberglass but the gel coat should be close to white, which means most of all the old paint is off.
I just stripped my bottom. Interlux says sand with 80 grit before applying a barrier coat. Also if you wait to long they say resand with 80 grit. I would follow the directions. You don't need to go down to the fiberglass but the gel coat should be close to white, which means most of all the old paint is off.
Correct Fred. Read on...
Actually I "zipped" off quite a bit of it with a carefully sharpened 2" chisel to get under the brittle paint but not gouge. Not as easy as it sounds but it worked well. I used stripper near the bootstripe and curves around the keel where I couldn't scrape. The gelcoat is in remarkable shape. No blisters, softening, chalking or anything. Just smooth and glossy. It is also surprisingly difficult to sand away the gloss as I did on the hull as a test and the cenerboard and rudder to refinish them. I will stick with 80 grit of which I already bought a load.
Actually I "zipped" off quite a bit of it with a carefully sharpened 2" chisel to get under the brittle paint but not gouge. Not as easy as it sounds but it worked well. I used stripper near the bootstripe and curves around the keel where I couldn't scrape. The gelcoat is in remarkable shape. No blisters, softening, chalking or anything. Just smooth and glossy. It is also surprisingly difficult to sand away the gloss as I did on the hull as a test and the cenerboard and rudder to refinish them. I will stick with 80 grit of which I already bought a load.
Bottom Sanding
A better and more controllable way to sand in prep for bottom primer (such as Interlux 2000) would be to wet sand with wet/or/dry paper on a hard rubber sanding block. The 80 grit seems a little agresive and 150 wet/or/dry might be slower. I add a couple drops of dishwashing liquid soap to a two gallon bucket to keep the residue from building up on the paper. Wetsanding with a medium hose spray should eliminate any residue left on the hull.
A better and more controllable way to sand in prep for bottom primer (such as Interlux 2000) would be to wet sand with wet/or/dry paper on a hard rubber sanding block. The 80 grit seems a little agresive and 150 wet/or/dry might be slower. I add a couple drops of dishwashing liquid soap to a two gallon bucket to keep the residue from building up on the paper. Wetsanding with a medium hose spray should eliminate any residue left on the hull.
Sanding stripped bottom
Rob, lots of advice here but most will leave you with a problem down the road.I do boat repair and maintenance for a living and unfortunately there's no short cuts in this work. You took the time to strip your bottom, no matter how you did it, now's the time to sand and barrier coat before bottom paint. It's well worth the effort and cost especially at resale time. Wash the gelcoat first with 202 solvent before sanding. Assuming your bottom is in good shape, no blisters, holes etc., sand with 80 grit first as this is needed to provide the tooth necessary for excellent adhesion of the coating. Make sure to sand off any remaining bottom paint as the barrier coat needs to be on the gelcoat to be effective. When sanding is finished clean off sanding dust and wash again with 202. I use Interprotect 2000. It's been reformulated to allow up to 2 weeks between coats without sanding. I just did a new Colgate 26 this week with 5 coats of Interprotect followed by 1 coat of Micron Extra Black and 2 coats Blue. As with any kind of paint work the bulk of the work is in the prep to achieve a good end result. Good luck. Gerry
Rob, lots of advice here but most will leave you with a problem down the road.I do boat repair and maintenance for a living and unfortunately there's no short cuts in this work. You took the time to strip your bottom, no matter how you did it, now's the time to sand and barrier coat before bottom paint. It's well worth the effort and cost especially at resale time. Wash the gelcoat first with 202 solvent before sanding. Assuming your bottom is in good shape, no blisters, holes etc., sand with 80 grit first as this is needed to provide the tooth necessary for excellent adhesion of the coating. Make sure to sand off any remaining bottom paint as the barrier coat needs to be on the gelcoat to be effective. When sanding is finished clean off sanding dust and wash again with 202. I use Interprotect 2000. It's been reformulated to allow up to 2 weeks between coats without sanding. I just did a new Colgate 26 this week with 5 coats of Interprotect followed by 1 coat of Micron Extra Black and 2 coats Blue. As with any kind of paint work the bulk of the work is in the prep to achieve a good end result. Good luck. Gerry
Gerry thanks and one more big question.
I had bought into Don Casey's and others opinion that if I have no problems with blisters now, after all this time ('84 boat) barrier coating is not needed and may actually contribute to their formation by trapping moisture. The boat will be in the water 6 months of the year, the rest on the hard. I've just finished sanding down to bare gelcoat, after a 202 wash, after scraping... Rinsed with water and no beading up anywhere. I was going to just go with Micron CSC but I allways like to hear from the pros. Do you really think I need to barrier coat seeing that the hull is in PERFECT shape?
I had bought into Don Casey's and others opinion that if I have no problems with blisters now, after all this time ('84 boat) barrier coating is not needed and may actually contribute to their formation by trapping moisture. The boat will be in the water 6 months of the year, the rest on the hard. I've just finished sanding down to bare gelcoat, after a 202 wash, after scraping... Rinsed with water and no beading up anywhere. I was going to just go with Micron CSC but I allways like to hear from the pros. Do you really think I need to barrier coat seeing that the hull is in PERFECT shape?
If you read the articles and statistics
After 20 years, if you haven't had any blisters, the chance of them showing up now and causing any damage are slim. Put on good bottom paint and go sailing. _/)
After 20 years, if you haven't had any blisters, the chance of them showing up now and causing any damage are slim. Put on good bottom paint and go sailing. _/)
Sanding stripped bottom
Rob, if your sure you have no blisters and the bottom is in perfect condition then the decision is yours. I would agree that if you haven't had a problem yet then you probably won't seeing that it has 6 months on the hard and mainly sailed in cold water. As far as barrier coat trapping moisture and creating a problem, if the hull is dry when you apply it then I don't know what moisture you would be trapping but I've never published a book. Sorry if I've added to your confusion,but I was just trying to help. If it were my boat I'd spend the $300.00 or so and do it. But that's just me
Rob, if your sure you have no blisters and the bottom is in perfect condition then the decision is yours. I would agree that if you haven't had a problem yet then you probably won't seeing that it has 6 months on the hard and mainly sailed in cold water. As far as barrier coat trapping moisture and creating a problem, if the hull is dry when you apply it then I don't know what moisture you would be trapping but I've never published a book. Sorry if I've added to your confusion,but I was just trying to help. If it were my boat I'd spend the $300.00 or so and do it. But that's just me
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