So... what do you guys think of this epoxy barrier job..?

[ErikFinn]

Fresh epoxy pics (CF compresses the pics quite a lot but click enlarge and see details):

[four winds]

Looks like the surface prep is lacking.

Lots of bubbles.

Not to mention it looks like epoxy resin instead of epoxy barrier paint. I have no idea if that is true or an acceptable alternative.

Not what I would think a barrier coat should look like. Though the experts may be more help than me, as I've only seen a couple barrier jobs. They didn't look like that.

[Scout 30]

This may be the result of not measuring the 2 parts correctly, not thoroughly mixing or both. The first time I used epoxy I didn't realize how important careful measuring & thorough mixing are & I ended up with something that looked similar to this.

[Franziska]

How did you prep?
Could also be outgasing of a solvent which was not EP compatible (contained oils for example) or did not vent off fully before EP application...

www.ladyrover.jimdo.com

[ErikFinn]

Thank you for your kind replies Ladies and Gentlemen. This is my friend's boat, job done by a shipyard. I was told it is barrier coating but I would not be surprised if it is epoxy resin. I have not seen them do the job, neither the materials they use. I am under the impression that the materials are some local produce. I went to the boat the other day to switch off the solar panels and found they had laid down a coat or coats. And thousands of bubbles in there. If not tens of thousands. Pretty much everywhere. I'm not an expert but I do know you can not have air bubbles in the hull. And this is the finishing lines of an osmosis repair job.. Yard suggested a light sanding.. And said that it's a slow curing epoxy and that the bubbles are caused by temperature variations.. Owner is coming to see the hull later this week.
My motive for posting the photos are to learn something and to hopefully get expert opinion and advice for my friend. Would Minaret approve a job like this?

[Franziska]

Properly catalysed and cured Epoxy forms an anti osmosis barrier.
Still proper barrier coat epoxy formulations create usually a higher film thickness and might even have tar or other additives in it.

www.ladyrover.jimdo.com

[Scout 30]

At a minimum I would sand this smooth. If after the sanding there are a lot of holes left because of the bubbles I would roll on a coat or 2 of west systems epoxy. If any of the holes are big it may be necessary to add some filler to the epoxy. It's important to wash the hull thoroughly before recoating to remove any amine blush. It's important to tip the epoxy after rolling it on to remove any air bubbles. I'd have someone follow the roller with a plastic spreader to make sure the epoxy gets in the holes & no new bubbles are left. After the last coat I'd let it harden & then wash it & sand it smooth again. Before bottom paint I'd put on a couple of coats of Interlux 2000 as a primer. After that I'd go with Trinidad for bottom paint.

WEST SYSTEM | How to use - Barrier Coating

[s/v Jedi]

I would reject the work. Like others mentioned, this is a bad job with all the bubbles and pimples, plus it is just resin, not the best barriercoat by far.

If the bubbles are at the surface then they may be able to be sanded open and filled. I would sand it completely, fill/repair, then do a proper barriercoat like 4-5 coats of Interprotect2000.



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[minaret]

This is caused by improper environmental control. This is what happens when you coat a boat first thing in the morning without heating the substrate first. The air trapped in the laminate expands as it heats up, both because of rising air temperature and because of exotherm. It has to go somewhere, and since a slow hardener was used there is plenty of time for it to find it's way out by making these bubbles. If the hull had been warmed to ambient temp first, or if they had just waited to apply the first coat till the afternoon, this would not have happened. I'd have them sand it heavily with 36 grit to be sure all bubbles are opened up, and then apply another coat or two to get back to where it was millage wise. It's not much of a barrier if it's full of holes. If the air trapped in the laminate is cooling instead of heating as the cure occurs, it will actually suck resin into the laminate as it shrinks, instead of making bubbles like this. That is how it's done.

[minaret]

Originally Posted by Scout 30

At a minimum I would sand this smooth. If after the sanding there are a lot of holes left because of the bubbles I would roll on a coat or 2 of west systems epoxy. If any of the holes are big it may be necessary to add some filler to the epoxy. It's important to wash the hull thoroughly before recoating to remove any amine blush. It's important to tip the epoxy after rolling it on to remove any air bubbles. I'd have someone follow the roller with a plastic spreader to make sure the epoxy gets in the holes & no new bubbles are left. After the last coat I'd let it harden & then wash it & sand it smooth again. Before bottom paint I'd put on a couple of coats of Interlux 2000 as a primer. After that I'd go with Trinidad for bottom paint.

WEST SYSTEM | How to use - Barrier Coating

Yes, like this. But heat it first too. Or wait till it's warm.

[barnakiel]

Yes. I too suspect bad timing.

BTW I never use pure epoxy only premixed barrier coats (epoxy base + additives). This job looks pure epoxy.

One of nice things about a premix is that you can use alternate colors for alternate layers. I am not sure how one achieves this with a translucent epoxy?

b.

[s/v Jedi]

Originally Posted by barnakiel

Yes. I too suspect bad timing.

BTW I never use pure epoxy only premixed barrier coats (epoxy base + additives). This job looks pure epoxy.

One of nice things about a premix is that you can use alternate colors for alternate layers. I am not sure how one achieves this with a translucent epoxy?

b.

There are more options; West System sells barrier coat additives to be added to epoxy and I hear it's good as well.

I used white Interprotect2000 because it was the only one I could get. Before painting a new coat I took a pencil and draw a pattern on the hull so I could see where I had painted the new coat and where not. You can also use a dry pigment, easiest would be a little carbon. The advantage of coloring lightly with a dry pigment is that you can do that per batch instead of opening another can. With 2-components you quickly loose product when you need a different kind every coat.

Then something I never saw done on a boat but I think it should work: the bubbles should pop when you wave a propane torch over them. This is how they do the casting epoxy on bars, tables etc.

[cruisersfarm]

Exactly what Scout and Minaret said. Exactly.

regular epoxy is a fine barrier coat, but it should be applied properly.

At least it's Thailand. Cheap do over/fix.

[Hamish_ct]

If that were my boat I would be very upset and make them sand It down and do it again.

One of the response here is correct it has a lot to do with a morning rush job and ambient air temp vs hull temp. But it also looks like instead of putting on 3 thin layers they glopped it all on with a thick roll.

I would argue indefinitely that they need to do a new job and they should pay for it.

[F10]

I just barrier coated my '78 S&S34. I put two coats of West Epoxy followed by 4 coats of Petit protect. I agree that job does not look good. Here is pic of my layers of coatings. As a fix I would sand down the epoxy (does not have to come off completely, just get the bubbles out and smooth) and coat with Interlux 2000e or Petit Protect.