New member and first post- I recently purchased a 1977 Mariner Ketch that has several eraser-size blisters on her hull. The previous owner said the gelcoat was removed about 18 years ago and he had epoxy ever since. He hauls it and has the bottom painted every three years. Three years ago the hull was stripped and 6 coats of West System epoxy applied and 3 coats of bottom paint. Now=blisters. My question is this....What is the sure fix for this reoccurring blister problem? And what if blisters go ignored? The boat is on the hard now and I'm trying to figure out what course of action makes the most sense. Any help will be greatly appreciated.
Blisters
- Thread starter setsail21334
- Start date
- Status
The bain of blisters.
There is a ton of information on this subject on the web. The trouble is I do not think that there is a sure fix for blistering that is guaranteed to last forever. Google, or web search for "osmotic blistering fiberglass boats" or similar. Here is a sample link from that search: http://www.oceanmarineservices.com/Osmotic%20Blistering.htm The previous re-coatings that the previous owner (PO) did to the boat may be part of the problem. In any case, you said you have eraser sized blisters which should be pretty easily dug out with a Dremel or similar tool and re-glassed once dry. Otherwise the blistering will spread until it becomes a potentially dangerous problem. Hopefully the blistering is only between the stuff the PO put on and the original hull. Good luck with this.
There is a ton of information on this subject on the web. The trouble is I do not think that there is a sure fix for blistering that is guaranteed to last forever. Google, or web search for "osmotic blistering fiberglass boats" or similar. Here is a sample link from that search: http://www.oceanmarineservices.com/Osmotic%20Blistering.htm The previous re-coatings that the previous owner (PO) did to the boat may be part of the problem. In any case, you said you have eraser sized blisters which should be pretty easily dug out with a Dremel or similar tool and re-glassed once dry. Otherwise the blistering will spread until it becomes a potentially dangerous problem. Hopefully the blistering is only between the stuff the PO put on and the original hull. Good luck with this.
Did your boat spend most of its time in salt water?
... then moved to fresh? If so the constant eruption of new blisters will probably continue forever .... and thats not usually a real problem for boats that eventually move from salt to fresh water. Blisters that only penetrate into the matting layer (the cosmetic 'cushion' layer between the gelcoat and the structural roving) are rarely ever a problem .... unless you plan to race the boat (needing an absolutely smooth hull, etc. The apparent definitive source on blisters is probably: www.yachtsurvey.com/blisters.htm which describes the hype that comes along with blisters. If you plan any remediation plan to carefully read all the blister info on this web site so you can make an educated decision. Many folks simply wont ever consider to buy a boat that had a DIY 'blister job' done ... as ultimately many times such 'DIY work' winds up as disaster and the hull comes close to 'destroyed'. What you dont want to do is a half-assed DIY blister job as most times such 'artistry' makes blisters much worse. If the blisters are few, not penetrating deep into the structural layers of the laminate ... the best course is usually to leave them alone.
... then moved to fresh? If so the constant eruption of new blisters will probably continue forever .... and thats not usually a real problem for boats that eventually move from salt to fresh water. Blisters that only penetrate into the matting layer (the cosmetic 'cushion' layer between the gelcoat and the structural roving) are rarely ever a problem .... unless you plan to race the boat (needing an absolutely smooth hull, etc. The apparent definitive source on blisters is probably: www.yachtsurvey.com/blisters.htm which describes the hype that comes along with blisters. If you plan any remediation plan to carefully read all the blister info on this web site so you can make an educated decision. Many folks simply wont ever consider to buy a boat that had a DIY 'blister job' done ... as ultimately many times such 'DIY work' winds up as disaster and the hull comes close to 'destroyed'. What you dont want to do is a half-assed DIY blister job as most times such 'artistry' makes blisters much worse. If the blisters are few, not penetrating deep into the structural layers of the laminate ... the best course is usually to leave them alone.
I personally think that blisters
are a birth defect, that is, your boat was either born with this potential disorder, or it was not. I believe the potential for blisters arises from the fiberglass curing process used by the maker of your boat. To me, that means there is no permanent "fix" for blisters. I also personally believe that barrier coating is not a worthwhile endeavor and the need for this procedure has been engendered by the people who make barrier coat products. While I have seen a few boats here and there afflicted with a pox of blisters over the entire hull, most boats that develop them only have a few here and there. If my boat had them all I'd do is drill/scrape them out, dry them out, and fill them with some thickened epoxy or MarineTex, bottom paint over them, and go sailing....
are a birth defect, that is, your boat was either born with this potential disorder, or it was not. I believe the potential for blisters arises from the fiberglass curing process used by the maker of your boat. To me, that means there is no permanent "fix" for blisters. I also personally believe that barrier coating is not a worthwhile endeavor and the need for this procedure has been engendered by the people who make barrier coat products. While I have seen a few boats here and there afflicted with a pox of blisters over the entire hull, most boats that develop them only have a few here and there. If my boat had them all I'd do is drill/scrape them out, dry them out, and fill them with some thickened epoxy or MarineTex, bottom paint over them, and go sailing....
Thanks
Thanks so much for your input. I guess my fix will be pop and scrape, let them dry then fill and paint. I'm looking to to put her in around mid October when I return from Iraq so she'll have plenty of time to dry. I'll check closely on my next haul-out. Until then....I can't wait to get back and go sailing!
Thanks so much for your input. I guess my fix will be pop and scrape, let them dry then fill and paint. I'm looking to to put her in around mid October when I return from Iraq so she'll have plenty of time to dry. I'll check closely on my next haul-out. Until then....I can't wait to get back and go sailing!
- Status