how to remove epoxy resin from below the waterline

[mariog]

Have taken my boat out of the water and antifoul and protective Veneziani epoxy resin is all damaged (blistered) till the gelcoat. So it has to be peeled of till the gelcoat. What do you formites suggest is the best way to remove it manualy as I have been qouted over a thousand euros to soda blast, and he is only one to do the job on the island. Thanks

 

[TQA]

health risks !

Whatever you do be very aware of the health risks associated with epoxy dust if any form of dry sanding is involved.

 

[Bosun Higgs]

when I had an epoxy coat fail, the yard removed it by peeling. You will get nowhere in a long time trying to sand it off.

 

[DownWest]

Epoxy melts at a much lower temp than polyester, so try a heat gun and scraper. When cleaning up the interior of my epoxy ply build, I used the gun to warm up the runs and blobs then the scraper just pulled them off.
Andrew Simpson of PBO had his hull sheathing bubble on a new build when they turned off the vac pump too early. Looked like an extensive job, until some-one suggested a heat gun. Came off easy. Sanding /grinding would be the pits.

€1k doesn't sound a lot for peeling, so the heat gun would be budget alternative as your labour is 'free'
A

As above, wear a good mask. If you just warm it, no prob, but some bits are bound to get hotter and the fumes are not so good.

Just reread your post, getting the a/foul off might be a prob before you heat the pox. Heating a/foul might not be a good idea..

 

[ccscott49]

After trying to get epoxy off a hull with all the above methods, I'd bite the bullet and pay for the blasting, cheaper/cleaner/better in the long run.

 

[vikinglish]

A "skarsten" scraper and lots of time and sweat ,or pay for the blasting!

 

[oldsaltoz]

Soda blasting will leave a far from perfect finish and will need filling and fairing anyway.

I have stripped the underwater section of 30 footers in less than a day using two 4 inch grinders, one running and one cooling down.

The wheel I use is designed to grind concrete. It takes a little practice to avoid minor over grinding but it rips the skin off in no time. I also use an adjustable height chair for the lower sections.

The trick is to have the grinding dust always heading toward the area to be ground, this leaves a clean hull and any spots missed can be seen as you go.

The disk has a red semi flexible backing so holding it just off flat to the surface being ground avoids ripples.

When ready to fair, get an old straight back hand saw and grind the tips of the old teeth off, the straight back will bend to the curve of the hull and save you a lot of material and sanding with a torture board.

Epoxy resin mixed mixed with 'closed cell' balloons is the way to go, I use 'Q-Cells' tiny glass spheres, a little harder to sand than Micro balloons but more water resistant.

Good luck.

 

[Elessar]

After trying to get epoxy off a hull with all the above methods, I'd bite the bullet and pay for the blasting, cheaper/cleaner/better in the long run.

I'm afraid it's not possible to blast sound epoxy, even if bubbled, off Grp and leave a decent finish. Sand off or peel off. You could weaken it by blasting and sand, but whatever it won't be straightforward. if they didn't abrade properly it might flake off, but it is a real task.