removing antifouling for gelsheild

johns

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do you have to remove all the antifouling before appling gel shield protection
if so what is the cheapest/easyist way to do it what would be the best sander
 

PeterGibbs

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You are taking on one of boat-ownings most unpleasant tasks - everything must come off, first with scraper, fine emerypaper(wet only) or liquid stripper. Having done it myself I can tell you it is a stumer! Use no mechanical aids if you value your lungs and the many microns of your precious boat they will remove - why remove it to replace it with shield?? Finish with acetone or the like to completely degrease or your new shield will just peel off.

Applying the shield requires the manufacturer's instructions to be followed, in most cases each layer has to be added before the previous one has cured, and don't skimp with the layers - you have to build it up to make it work!

When you've finished, you will feel good; along the way you will ask yourself several times why you embarked on it !!

Good luck,

PWG
 

ccscott49

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If I were you, I would get the bottom blast cleaned with the "Farrow system" advertised in the mags, this is a plastic medium wet blasting system, which will remove every trace of antifoul and not damage the gel coat, you can then flat the bottom and apply the gelshiled, much easier cleaner and more efficient. It will cost monbey, but will be a better job in the long run, try them for a quote. IMHO It might even "key" the surface for you to just apply the gelshiled, I'm not sure aboput that.
 

vyv_cox

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I fully agree with Colin. I have used chemical and mechanical means to strip layers of antifouling and it is very hard work. If you have access to one of the specialist yacht blasters it must be worthwhile to employ them.

Just on the financial side, the chemical method will cost at least 60 pounds for a 35 ft boat. Mechanical removal will need some equipment, I have found a hook device attached to a vacuum cleaner to work well, although some didn't. That costs somewhere around 12 pounds, and I bought an orbital sander specifically for this job, cost about 40 pounds. Makes the blasting method seem much more attractive.

To get gelshield to work properly you need to remove every last speck of antifouling, another reason for going the blast route.

I have never used them, but <A target="_blank" HREF=http://www.symblast.com/>http://www.symblast.com/</A> seem to know what they are talking about. Used to be called Southern Blast.
 

maxi

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Don't even think about applying any epoxy unless you can guarantee the hull to be dry (mechanically dry & not just touch dry) otherwise you will be paying to create problems for the future.
 

brianrunyard

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\"Stripit\"

DO NOT SAND.
I removed several layers of antifouling last winter and GelCoated my hull.
I removed the antifouling with "Stripit" (think thats the name, will check when I get home) approx £8 for a 2.5litre tub. It has the appearance of wallpaper paste, brush it on, leave 24 hours, don't let it dry, pressure wash off. It was as easy as that, no rubbing, scrubbing or hard work involved.
Words of caution, use goggles, gloves etc. as it's corrosive and will burn the skin.

Brian
http://homepage.ntlworld.com/brunyard
 

miket

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Totally agree with this, whatever method of removal is used.

Have your surveyor test the moisture content when boat first removed and take his advice as to when it is dry enough to continue.

I had an old Freeman 32 motor boat done (gel coat removed as osmosis rife) and it took from October to April in a heated and dehumidified shed to pass the surveyors test.
 

steffen

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Re: \"Stripit\"

Brian,
If you check the name pls also check what the active component in the stuff is. I have never seen it in Holland but assume there is a suitable substitude i can find if i know what makes StripIt work.
Sofar have tried normal paint stripper with some degree of succes. It takes three treatments to get to the bare gelcoat.
 
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