Help! Epoxy peeling

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Gwoloshyn
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Help! Epoxy peeling

Post by Gwoloshyn »

Guys, I just finished applying my 3rd weave fill coat on my TNT and my epoxy is peeling off. I applied the coat, allowed it to fully cure (because I didn't have time to do another coat) then gave it a quick once over with a tack cloth. I did not sand. Should I have sanded before applying another coat? What is the proper procedure for preparing for another coat of epoxy if the previous one has fully cured?

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gdcarpenter
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Re: Help! Epoxy peeling

Post by gdcarpenter »

Chemical bond or mechanical bond necessary, so apply second coat while first one 'green' or if cured than sand and clean.
This is my first, last and only boat build.

http://www.gdzipbuild.blogspot.com

upspirate

Re: Help! Epoxy peeling

Post by upspirate »

I would peel and sand down to the first layer of epoxy, scrub with scotch-brite pads with mixture of water,dish soap and ammonia to get any anime blush off.

Then I'd scuff sand with 80-120 grit and re-epoxy

You probably had some blush, and too smooth a surface for the other coats to stick.

Good thing it peeled now instead of when you were out on the water....it probably wouldn't have hurt anything then,but it would have been much more work!!! :wink:

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Gwoloshyn
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Re: Help! Epoxy peeling

Post by Gwoloshyn »

Thanks. How would you suggest I clean the surface after sanding? I used a tack cloth with good results, I couldn't pick up anything with my hand after using that.

What about a power washer with a high fan angle? Seriously :)

upspirate

Re: Help! Epoxy peeling

Post by upspirate »

I have just washed down with water and dried then a wipe down with alcohol.

I can't remember,but I think I read that tack cloths leave some residue that is not compatible with a lot of coatings,epoxy was one of them I believe

upspirate

Re: Help! Epoxy peeling

Post by upspirate »

When you re-epoxy,plan for doing it if you can when you can re-apply the coats when they are dry to touch,but still green stage.That way you don't have to scrub and sand between coats again.

I'm in the process on my skiff where I have to scrub and sand all around the battens on the inside cause I didn't plan well....that's a lot of fun!! :roll: :?

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Gwoloshyn
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Location: Upstate NY

Re: Help! Epoxy peeling

Post by Gwoloshyn »

Warren, I plan to do just that over this holiday weekend. The majority of the boat has epoxy that looks to be bonded well, would it be OK to leave this as it is and apply my next coat over it? My reasoning would be that after applying more coats I would create a hardened shell around the hull and I shouldn't be risking any more peeling away since it's covered. Am I right?

upspirate

Re: Help! Epoxy peeling

Post by upspirate »

If you have doubt, sand it down to secure stuff.

That is a thin shell that peeled in the picture!!! :wink:

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billy c
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Re: Help! Epoxy peeling

Post by billy c »

much easier to get a fresh start now then after you have put the finish on.
i vote to strip the whole thing down so you know what you have for a base
-Billy
(insert Witty phrase here)
Billy's Belle Isle website

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