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Post by joker64 on Mar 10, 2013 11:51:11 GMT
Ok. Here's the situation. I'll skip the history of the purchase. Suffice it to say, I am the third owner of a 1993 SO44 with the long keel. I moved it to a pretty brackish area of the Med, with the anti fowling provided by the seller. After a year of so, the bottom was a mess. I co-own the boat, and we sanded the bottom coat (not to the primer), and applied a compatible anti fowling. It has been in the water for two years, and the growth was so bad, that we had it towed the 500 meters to the boat yard to have it put on the hard. It was scraped, and washed. We decided to get a jump on things, and remove as much of the anti fowling as possible in an effort to later apply a better product. We found blisters. We only had time to uncover about 1/3 of the boat at the bow area, and I estimate about 5 small blisters per foot. However, we also found that there had been a previous coat of epoxy applied, and the blisters appear to be under this coat. I have to imagine that the boat previously had blisters, and this was the repair attempt. We left the boat as it was, to go home and develop a plan; knowing that we still don't have the 'whole story'. We will go back to the boat this next week weekend with the following plan. 1. With a standard wood planer (I know about the GelPlaner, and other diy products, but due to the shape we 'think' we can do 80-90% with this, and the rest with a sander), we plan to remove the gel-coat. 2. We then plan to take a look at the mat and see the condition of the lay-up, blister placement and depth, to determine if the mat should be removed as well. 3. Should the mat be so bad, ie showing lots of voids, blisters within and underneath, and with lots of blisters throughout, then we will consider removing the mat as well. 4. Let it dry out as much as possible. (This will be part of our problem as we will only plan to leave it on the hard for a few months, don't have access or money for the HOTVAC, and probably won't find it cost effective to leave it out of the water for the whole summer. Research has revealed that the 'dry-out' is somewhat difficult as well.) As I know this IS important, but will always be a balance between time and money, I am open to suggestions. We will then wait as long as we can for the hull to dry out. I considered using a moister meter to determine the condition prior to treating the hull, BUT I realize that I don't have the expertise to interpret the multitude of variables accurately, even if I bought a meter, IR methods aren't really a viable option in Italy, and so, might be limited to the cellophane taped onto the hull method. We will then plan to apply an Italian product from cecchi called C-system, www.cecchi.it/italiano/english.html It costs a fraction of products like International, and has a good reputation here. I 'think' that we have considered the product and how to apply it. We are both diy'ers, and capable with out hands and tools, and have done other, perhaps larger projects, with success. The boat yard where we have the boat cannot be relied upon, and at present we are land locked. So, this prohibits us moving the boat. Some of the questions i have are: 1. The factory installed bow thruster (apparently, as it looks never used from inside) was covered over. Is there any reason not to open it up, and put it to use. 2. I know that the keel is cast iron, but I can't find any information to know i it is encapsulated or not. Also, I am having a bit of difficulty in finding information of how to treat the keel...ie sand down to the iron/grp and recoat? I suppose the first thing is to know if it is bare iron, or encapsulated. Anyone know? 3. I have noticed other repairs on the hull under the epoxy. The epoxy that was attached to these repairs scraped away easily. It makes me concerned that a new treatment on top of this filler might not be compatible. How can I know? I have never done a bottom job, other than anti fowling, and am open to any and all suggestions.
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Post by MartyB on Mar 10, 2013 16:51:06 GMT
With out getting into a total how to....generally speaking...
Blisters one wants to sand back to gel coat, break sand the blisters and let them dry out. Could take a month or two depending upon temps. Apply epoxy then bottom paint.
Keel is the same, Strip to bare iron, epoxy then bottom paint.
marty
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Post by joker64 on Mar 10, 2013 17:56:00 GMT
thanks Marty, we are more or less planning this. I just have a bad habit of planning for the worse, and sometimes making the project larger than it needs to be in an effort to to it 'more than right'....I guess that might be called over engineering.
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Post by sailbleu on Mar 10, 2013 21:33:02 GMT
What a hell of a job , but technicaly a piece of cake. Be it with a lot of elbow grease 1: Get the bowthruster in use , maybe it was closed for racing, drag you see.But maybe you can first check out no leaks to the inside of the boat are present.I presume the holes on both sides are closed with fibre ? You didn't explained that very clearly. 2: Grind the keel to bare iron and reshape it using epoxyfiller. Make the filler yourself with (cheap) epoxy resin and added aerosil or glassbubbles. Mind you , that stuff is as strong and hard as can be , sanding it will be a pain in the .... Once smoothly sanded give it 4 or 5 coats with , again , epoxy resin. Afterwards the AF goes on top. I estimate a weeks work to get the keel on track again. Remember to degrease before applying the epoxy and try a wet in wet procedure for the coats. If not , sanding between coats is a must. 3: Use a gelplaner to get the gelcoat off , your boat is contaminated with osmoses.That will be the hardest part , removing the gelcoat without damaging the fibre. I wouldn't use a normal planer though. Let the hull dry as long as possible and rinse/clean it frequently with hot water to get the acid out. The Med climate will help you with the drying. Then apply a few layers of glassfibre (use the fine finishing fibre for that) and epoxyresin. Finish off with epoxyfiller again and sand the lot. You decide how the end result will look like of course. All will depend on the time and effort you're willing to spend. Then the 4 or 5 coats colored ( grey for instance) epoxy. Remember to allow as many bubbles as possible to get out of the mixture ( the use of a slow curing kind of epoxy can help you out ) , if not they will manifest themselves on the hull as very small craters . Been there , done that you see. Dont , and I repeat , dont use them fancy and expensive primers , ready made fillers or other commercial products , they will make you bleed financially.Go for the cheap products I mentioned earlier. Check www.HP-Textiles.de . Good luck
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Post by joker64 on Mar 11, 2013 9:03:13 GMT
sailblu,
Thanks soooo much for the time to reply. Your advice is well taken, and I will be sure to follow as much as I can. I wish I had access to a Gelplaner, or the money to buy one. Unfortunately, we will be restricted to a standard plane, for which we are currently evaluating how to use it so as to not make any grave errors. I know that it won't be as fool proof, but hope that our caution will either stop us in our tracks if we find it's not working, or guide us with caution. What can't be reached will have to be done with pain staking sanding.
I didn't mention what material the bow thruster has been closed with coz I don't know. At the moment we only se filler, and I don't know what is behind that. I would imagine glass, but as we decide to open it, we will definately see.
Our boat is in South Italy, and unfortunately, when you have a problem like this the Boat Yard (I use the term loosely) considers everyone an idiot, only they know the 'right' way, and if you want their help they basically have you over a barrell.
This site, and the plethora of online articles, are indispensable.
I know that our biggest challenge is going to be time, as the boat is about 5 hours away, and the other owner and I always have to coordinate time off, family etc. So, we will have to watch ourselves so as not to cut corners on the laborious stuff like sanding.
This C-system that we plan to use has a nice filler system. Maybe it is the same for all treatments, I don't know. But, they use a grooved trowl, similar to what one uses for laying tile. This ensures the correct depth. Then you have to go back over the grooves and fill them in. I probably sound like a newby, as it seems so obvious that I imagine the other systems also use this to get the right thickness.
I head to the boat this Saturday. I'll post what we did and a few picks when I get back.
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Post by sailbleu on Mar 11, 2013 9:41:12 GMT
The way I see it , all (final result) depends on the first preparation , getting the gelcoat off ! If do a nasty job , using a woodplaner , you will end up with a hull looking like a waveplate. Try solving that with the C-system . On the other hand if you use the finishing fibreglass (fine structure) in combination with epoxy resin you can build up the thickness of the ' new gelcoat layer ' as you please. Work your way up to the waterline , I suppose the border where you will be removing the old gelcoat. Leaves you to correct the unevenness with the filler I mentioned. I could be wrong of course , but there's a big risk the C-system will be very disappointing with regards to an even hull surface. Again ,...it starts with a good gelplaner , maybe you could try and rent one, or even buy one on ebay , you will surely be able to sell it when the job is done. Maybe you could consider having this part done by an experienced professional , it's the most important part you know. My estimation for this job with 2 man will be 3 weeks top. A caravan on a nearby camping would do wonders , 5 hours away What a waste of time. Regards
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Post by joker64 on Mar 11, 2013 11:52:46 GMT
Hehe, hey there sailbleu.....I am noticing that you are in the neighborhood.... I would rent one, IF I could find one for rent. I haven't been able to find one on EBAY, and if you've ever done any work in Italy, paying someone to do it is out of the question for a few reasons. One is that of trust, another is that of ensuring competence, and the last will most definately be the price.
Well, camp grounds are near, but I have a house just a 5 minute walk away. Not where I live, but just a kinda summer place......place to keep the boat really.
What are you suggesting?
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Post by MartyB on Mar 11, 2013 14:44:51 GMT
NOt sue what options you have, would assume similar to here in the NW US, but having someone soda blast the hull has been poplular around here. A company comes in and uses small pellets and in a nutshell, sandblasts off the existing paint/epoxy to bare gel coat. Considering your time to literally sand off the paint, its not too bad a fee. Especailly when you consider how toxic the sanding dust is. Locally any how, they put plastic tent off all around the boat, the machine they use is blasting and collecting the debris at the same time. They can control how hard they can blast the paint off, so they can go down just before, or even blast the gelcoat clean if need be. With very little debris outside of the boat, you not potentially breathing the dust..... if my marina was not so strict about ONLY sanding with a vacuum attachment, I would do this, or will move the boat 10 miles away to have another yard marina that will allow this to occur.
sailbleu got into the how to in more detail than I did initially. Reason being, as there is to a degree, more than one way to strip the bottom, more than one type of epoxy brand etc to add back......
Marty
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Post by sailbleu on Mar 11, 2013 15:32:22 GMT
I would suggest to keep looking for a gelplane , wouldn' t do it without one. I'm well aware of the outrageous prices in Italy you know , I've spent all my summer vacations (and the last 25 years also the ski vacations) over there. Speak some Italian , seen all the islands , except the no can do ones like MonteCristo and Pianosa. Oh yeah , I would like to see Lampedusa in the future , but I'm not sure whether I'll meet many original Italians ,if you catch my drift.
Other suggestions , buy a new gelplane , be kind to it and sell it again after the job for 3/4 of the price on ebay or what. I figure you get the gelcoat off in 2 days.Very clean and nice. But first give it a try out on your neighbours boat to get the hang of it :-) :-) :-) Buy the plane by Saving money on the C-system and use the ever so cheap epoxy resin of HP-Textiles.de
Regards
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Post by sailbleu on Mar 11, 2013 15:44:28 GMT
NOt sue what options you have, would assume similar to here in the NW US, but having someone soda blast the hull has been poplular around here. A company comes in and uses small pellets and in a nutshell, sandblasts off the existing paint/epoxy to bare gel coat. Considering your time to literally sand off the paint, its not too bad a fee. Especailly when you consider how toxic the sanding dust is. Locally any how, they put plastic tent off all around the boat, the machine they use is blasting and collecting the debris at the same time. They can control how hard they can blast the paint off, so they can go down just before, or even blast the gelcoat clean if need be. With very little debris outside of the boat, you not potentially breathing the dust..... if my marina was not so strict about ONLY sanding with a vacuum attachment, I would do this, or will move the boat 10 miles away to have another yard marina that will allow this to occur. sailbleu got into the how to in more detail than I did initially. Reason being, as there is to a degree, more than one way to strip the bottom, more than one type of epoxy brand etc to add back...... Marty Marty , what I understood is that the old AF is already scraped off. I do know what that means , I did the same more than a year back , took me (on my own) 5 days (6 hours/day) to get it done. But soda blasting doesn't get the gelcoat off as you well know. Sanding it off is also an option , be it a ridiculous one no doubt. Neverless I've seen a friend do it 2 years back , small boat , took him a month , a truck of sanding pads and a river of sweat. Horrible sight. Regards
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Post by MartyB on Mar 11, 2013 17:10:32 GMT
sailbleu,
Had to go reread the original, and yes, it appears as if the AF is already off, so the soda blasting will/would not do anything joker64. The final part will be literally sanding at this stage, opening all the blisters and letting drain for some period of time, depending upon the temps, humidity etc, then rebuilding everything back up.
I personally have not heard of a gelplane, need to look that one up later today. could be an interesting tool. I wonder if one could rent one locally at a rental yard of some sort. I can rent 7-10" disc sanders with vacuum attachment if one does not want to buy one, or potentially ruin there own!
Marty
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Post by MartyB on Mar 11, 2013 21:16:23 GMT
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Post by Don Reaves on Mar 11, 2013 21:18:22 GMT
A common shortcut when you have a small number of blisters is to remove the gelcoat at each blister with a small round grinding tool. Then you have to fair the surface and apply a really good epoxy barrier coat, followed by antifouling paint. This significantly reduces the entire job, and doesn't require a plane. I did this on my Catalina 30 many years ago, and the blisters never reappeared.
Of course, it doesn't provide the opportunity to work on areas where the gelcoat looks good but really has moisture problems.
Good luck with the job. I hope I never have to go that far with my Jeanneau. Don
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Post by sailbleu on Mar 12, 2013 6:23:03 GMT
Don , your procedure is also an alternativ. But you can never be sure if more blisters will appear later on. Then it becomes a never ending story. The reason for osmoses is the lack of a good epoxy barrier. In the old days it was simply not done . Therefor it would be wise for owners to scrape off the old AF layers , sand the hull completely and apply several layers of epoxy resin. Although my hull had a barrier coat (only a thin one by jeanneau you know) Last year I've put on 3 colored (grey) as a primer and 2 extra with copper oxide , the home made copper coat that is. Which wasn't a succes , the copper coat I mean. But I do have 5 coats of epoxy on the hull now, reassuring me that osmoses is a thing of the past for me. I advise everyone to do the same before being confronted with Joker64 ' nightmare. Call it a pre-emptive action.
But maybeyou coul be right about patching up things , considering the lack of time , only a few months to do this major job. You normally need a complete winter to dry the hull after it has been de-gelcoated. Joker64 could take the risk of only adressing the blisters like you suggest , that way the integrety of hull - and I mean that in a aestetic way - is not comprimised. This way the shape will remain intact and patching up is a lot easier. Never the less the grinded spots need some drying and rinsing . All depends on the number of blisters of course.
Regards
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Post by joker64 on Mar 12, 2013 17:15:04 GMT
Sailblueu, you've convinced me about the Gelplane. Given time, I am sure that we could construct a similar machine, and maybe even successful, as we have access to many experts and workshops for that kind of thing. HOWEVER, time is of essence. I started looking yesterday and can't find one online used. I found the Italian distributor, who no longer is a distributor, but is asking some former clients to see if they can help us with a used one. If I can find one and get it by Friday, I will buy it, and try to re-sell after the job is done. But, so far I'm not finding anything. Keeping my finger's crossed.
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Post by electricmonk on Mar 12, 2013 20:12:16 GMT
I ve had a bit of experience with this. In the end you have two choices, remove all the gel coat or just "knock back" the blisters, fill and re coat.
The worst case I had any dealings with was a 40ft ketch, not a Jeanneau it had about 10 1" dia blisters per square foot all over the hull.
First we stripped off all the AF
Then we ground the blisters away with an angle grinder inspected the mat (it smelt of vinegar) and washed it every day for a week with fresh water until it didn't smell any more and left it to dry, three months later (it took that long) the craters were filled re gelled and faired.
that was five years ago, the hull is still in good order as far as I know. You can strip the whole hull with a planner but its a lot of work and not really necessary but the osmosis clinics will advise it because its a lot of work. . . .
Osmosis has nothing to do with fouling, its a resin problem.
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Post by sailbleu on Mar 13, 2013 5:55:11 GMT
Exactly my sentiments electricmonk. If I was in this situation all would depend on the time I had to finish the job . In this case I would definitly go for the patching up , considering the short available time , transportation and the summer season that is around the corner . I would simply take the risk of doing a major patch-up-job. There's a fair chance all (or most of them anyway) osmosis spots have manifested themselves I would fill the holes with epoxy filler though , not gelcoat.
Maybe joker64 is under estimating the complexity of this job. And it starts by using the gelplane in a way you dont damage the glass . Then reshaping the hull with be it the C-system or finishing fibreglass . That could turnout really disappointing considering the limited timeframe. I vote for patching up , sometimes you have to take some risks in life.
Regards
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Post by electricmonk on Mar 13, 2013 17:51:33 GMT
sorry of I did n't make it clear but the blisters were filled with epoxy filler then re-gelled and faired, in actual time at work it was only a few weekends - after the daily wash downs had finished.
Once you get going you can fair off the gel very easily because there is a lot of original gel around as a datum, after that its just AF and launch.
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Post by sailbleu on Mar 14, 2013 5:40:18 GMT
Well again , I wouldn't take the effort of adding gelcoat on top of the epoxy filler you know. In my opinion it would be a waste of time and money. Once the hull is renewed the epoxy coat (barrier coats) will cover the paching up completely , so it makes no difference whether you use gelcoat or not. But remember , if you make your own filler ( epoxyresin with aerosil or glassbubbles ) - and I strongle suggest you do - you will have a hell of a time sanding down the patches , so be very discrete with the filler . That means not putting on a mountain of filler on each patch , try filling up the holes in stages. The gelcoat around the patches is softer than epoxyfiller , therefor you run the risk of sanding down the wrong stuff. Dont worry if the final result (after patching up and barrier coats) looks a bit wobbly , once the selfpolishing AF (put on 2 coats of that stuff preferably when the last epoxy barrier coat is stil tacky so you get a kind of chemical bond) is on you will be able to smoothen the hull after a few years when you apply new AF because you always have to sand the old AF before adding a fresh coat. Selfpolishing AF is easy to sand , you can make all bumps and unevenness go away.
Well , maybe joker64 chooses to get rid of the gelcoat completely with a proper gelplane , in that case I would really like to so some pics of that procedure aswell as the results. I've seen a professional do it some years ago , it looked quite easy , but it always does untill you try it.
I would urge him to reconsider his plan of attack though , adressing the blisters on a individual basis holds less risk of a dissappointment.
Regards
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carstenb
Junior Member
Posts: 11
Country: Denmark
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Post by carstenb on Mar 15, 2013 12:17:17 GMT
Some friends are doing this to their boat (not Jeanneau). You can shorten the drying time a bit by using a heavy duty hairdryer. Yes it is a major effort, but after rinsing out each of the osmosis holes, you can "blow dry them"
Might need more than one hair dryer
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Post by sailbleu on Mar 15, 2013 17:37:32 GMT
Some friends are doing this to their boat (not Jeanneau). You can shorten the drying time a bit by using a heavy duty hairdryer. Yes it is a major effort, but after rinsing out each of the osmosis holes, you can "blow dry them" Might need more than one hair dryer Couldn't agree with you more , about the forced drying that is . But there are a lot of blisters you know. Regards
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Post by joker64 on Mar 15, 2013 18:09:23 GMT
Thanks all. I will head down to the boat tomorrow, and hopefully start on Sunday. I am not going to rush things. If I have learned anything in my almost 50 years, it is to learn from those who have gone before me. Soooooo, I am forgoing any ideas about using a regular planer, or even a gelplaner at this stage. I will re-evaluate the extent of the problem, and attempt to just open up what blisters there are, wash and let dry. I should have someone that I can send there about every day to wash the boat down, and I will just let it dry as long and then treat accordingly. Then we will plan to get it on the hard perhaps next year, and see how things have held up. Then we'll decide what needs to be done, and do it properly. Thanks for all the advise. If I can, I'll upload some pics when I return.
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Post by joker64 on Mar 20, 2013 21:43:11 GMT
Ok. A few days at the boat and we did the following:
1. Sorry for unintentionally misleading. We had not removed all of the anti-fouling. Only on the first third near the bow. So, we bought Veniziana, AcquaStrip and worked on the rest of the bottom. There was a learning curve associated with dwell time, and application process, but I think we worked it out.
2. We then only got about 1/2 of one side sanded down to what appears to be an epoxy coating over the original gelcoat. It is only once we have sanded down this far that some 'blemishes' start to reveal themselves.
3. While working the first day, a man stopped by, who we suspect was a surveyor who was working on a nearby boat purchase. Once I told him the story, his comment was,'It definatly IS NOT osmosis, that I would be able to see it and smell it from here, but I cannot'. Ok, I don't know what all that means, but there is something.
4. What I see are small circular shapes about 1cm in diameter, and smaller. There appears to be a crack in each one, and only when pressed a liquid comes out. Nothing seems to be under pressure (It has been out of the water about 3 weeks now), and the fluid has virtually no smell. If I stick it right up my nose, I might be able to say that there just might be the slightest smell of resin. The fluid is sticky to the touch. I would estimate that on one half of the starborad side there are about 20-30 blemishes.
5. My theory (for what good it is), is that sometime in the past someone decided to apply a barrier coat. Perhaps the gelcoat wasn't so dry, and moisture was trapped underneath. Perhaps there were irregularities in the gelcoat making the epoxy of varying thickness, and none too think anyway. It appears that in some spots the epoxy easily chips away. Once we apply a sander to the epoxy it reveals the gelcoat high spots underneath, that in turn want to release the moisture underneath. I know....even I can shoot some holes in my theory.
6. The conclusion is that I an VERY HAPPY that we didn't tackle this job with a gelplaner, though I am have not convinced myself yet that this won't be necessary.
The next trip will involve removing the rest of the anti-fouling, sanding down the hull, and trying to delicately open up the blemishes/blisters. Then just leave it in the sun for as long as we can.
Any further ideas?
I will try to post some pics, when I can figure it out.
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Post by sailbleu on Mar 21, 2013 6:08:07 GMT
When you open blisters on a hull and they smell like acid you have an absolute case of osmosis If you want to be sure , buy or get some litmuspaper and hold it against the moisture of an opened blister. If it turns red you will no doubt turn red also. But now we get the full story , I stick to my (and others) last suggestion , adress the blisters and not the hull. I think point 5 in your summery explains it all . If you only have 20-30 blisters on 1/4 on the boat , being about 100 on the complete hull , there's no other sensible option besides grinding the blisters away and filling them up with epoxyfiller. Apparently the barrier coat was not put on in a proper way , so get rid of everything. Maybe sand- or saltblasting is recommended , this way you will go all the way to the gelcoat (and a bit deeper) and you will get a complete picture .
But you should never of used an AF stripper , that stuff isn't worth it's price and you really make a mess of the hull. Besides , if you insist on applying it's best you put it on and cover it with some kitchen plastic . That way it doesn't evaporate or dryes that quick en keeps active for a longer time. But use a scraper , it's cheap and effective . And it's also a very good exercise , who - in case of overweight - needs a diet when you can scrape the hull of your boat.
Good luck
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Post by electricmonk on Mar 21, 2013 8:43:39 GMT
My theory (for what good it is), is that sometime in the past someone decided to apply a barrier coat. Perhaps the gelcoat wasn't so dry, and moisture was trapped underneath. Perhaps there were irregularities in the gelcoat making the epoxy of varying thickness, and none too think anyway. It appears that in some spots the epoxy easily chips away. Once we apply a sander to the epoxy it reveals the gelcoat high spots underneath, that in turn want to release the moisture underneath. I know....even I can shoot some holes in my theory.
This is classic osmosis brought about by a problem with the resin mix in the rovings layup or a lack of resin in the layup when the boat was built. Because of the age what you see is probably all there is. Don't be bashfull when you open up the blisters, as I mentioned above use an angle grinder "end on" and make circular pits in then hull, they wont be very deep.
Lots of water to wash out the acid then it must be left to dry COMPLETELY - in the UK June is a good month for this, low relative humidity and warm winds. Or you can rig up some sort of tent - but they don't work very well. If you know a surveyor see if you can borrow a moisture meter.
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