Does this sound right?

sighmoon

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After escaping from her mooring, and spending 24 hours bouncing on the rocks, my boat was repaired by a local yard.

She's fibreglass, over a foam core, with a layer of epoxy on the outside. She was badly scuffed, but not holed.

After 6 weeks back in she was taken out of the water for the winter. There are some holes in the repaired area, and it seems a bit soft. The holes are a few milimeters deep, and a few mil wide.

A helpful, passing surveyor had a look and put his moisture meter up to the hull - it went off the scale in the repaired area, but was at zero on the original hull surface.

So I called the yard that did the work. He said the boat was repaired with epoxy, but there is a layer of filler which can easily be shaped and sanded over that, (as sanding epoxy takes days) and it is the filler that I'm referring to. I'm questioning the wisdom of that approach - as the saying goes 'nothing sticks to epoxy except epoxy'. Surely a non epoxy filler, over an epoxy surface can be expected to fall out every time. It also seems daft to use something absorbant in an underwater application. Or am I missing something here?

Even if an easily sanded layer is the 'done thing', I would have thought a layer of epoxy ofver the outside of it would have been a good idea.

The yard also said the moisture is probably coming from inside the repair. This seems unlikely to me, as if they really did repair it with epoxy, any moisture inside would be trapped inside, as it wouldn't be able to cross the epoxy, surely?

I was paying for the repair out of my own pocket as th insurance was only third party, so he was trying to keep the cost down. Eventually I paid for three days work to reshape the skeg and rudder, and to repair the hull. The repair looked generally loveless at the time (but we're keeping your costs down) as they used a rather different colour to paint the topsides, and I could see fibreglass cloth on the skeg (so he put some isopon P40 on it just before launch.)

Does what the yard are saying sound reasonable?
 
Golden rule in our yard is epoxy on epoxy , never anything else. There are quick curing epoxy fillers that are easy to sand, but its always a problem with cost. epoxy is 20 times the cost of car filler.
 
Thanks boatbuilder, that's about what I thought. What would be the name of a good, easily sanded epoxy filler, for instance?

Simon
 
A filler made of microballoons or glass bubbles is easy to sand.

I may have missed the point, but I think the man at the yard has a point. If the surveyor's meter went off the scale over the repaired bits, it is plausible that the moisture is underneath the epoxy repair, in the foam core.
 
hi this is how i fixed mine ...1/clean out damaged area...2 dry out with a hair dryer .....3/... mix epoxy res with talcum powder til you get a nice mix .....4/ fill damaged part then sand ...then duco will look like new and will not fall out or crack..you can do all this your self . my thoughts are you should take it back tell them to do it right...
 
That's as it should be. Epoxy over Polyester but never the other way around. Sounds like a cheap and cheerful job. It may well be that the water is under the filler (or in it) suggest removing all filler and checking for moisture again. If it's OK then re-fair with epoxy, not Isopon!
 
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If the surveyor's meter went off the scale over the repaired bits, it is plausible that the moisture is underneath the epoxy repair, in the foam core.

[/ QUOTE ]

If the water was under the epoxy repair, would it be able to pass through the epoxy barrier to the filler layer? My understanding (which I'm trying to clarify) is that epoxy is completely impermeable, and so any moisture underneath it, would stay there(?)
 
Even Epoxy isnt totally impermeable but it would take a long time for it to register in the polyester filler unless the epoxy was undercured and had Amine sweat atracting moisture between Epoxy and polyester layers however a moisture meter would pick up moisture in the foam core. In this type of construction the last thing you want is trapped moisture between the "skins" as it can contribute to delamination over a far greater area than the actual repair
 
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