OT: Fiberglass expert hekp needed

Here's the story: The Century fiberglass cap on my pickup is flaking. I'm familar with 'glass and have never seen this kind of failure- it looks like (and could very well be) that the previous owner refinished the cap with some kind of clearcoat. If that is the case, he did a great job- there is no evidence of overspray. The 'flakes' are clear, which makes me think that this is not a gelcoat issue. A pressure washer will remove the clearcoat, but it's slow going. Anyone here ever run into this?

-Carl

Reply to
Carl Byrns
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While there is a clear gelcoat, this sounds exactly like what you think it is.

As you probable already know, gelcoat is a hard brittle resin.

It doesn't "flake". It chips, cracks, and sometimes pops loose in large chunks.

But when it does, you will almost always see the raw fiberglass layer underneath.

FWIW...

Richard

Reply to
cavelamb himself

I'm not sure if I can be of any "hekp", as I'm not an expert.

As Richard mentioned, there are clear gelcoats.. typically used for metalflake finishes on boat hull shells. Or someone may have clearcoated over the original paint. I've seen some applications of acrylic enamel with hardener, applied so thick that one might assume it was gelcoat.

I would suspect that the peeling clear coating is an automotive clearcoat applied later to try to make the cap look new (peeling due to poor surface prep and/or improper application techniques). If it was gelcoat peeling, it would seem likely that the peeling was from a manufacturing defect/fault, where the color didn't bond/fuse properly with the clear gelcoat (I think the color coat would also be a gelcoat, though).

I kinda doubt that someone would actually try to spray clear gelcoat over a painted finish (as it's very likely to fail), but people request a lotta weird types of procedures. If someone asked me to apply gelcoat over paint, I'd decline.

I don't know what type of solvent test would indicate what the material is, although gelcoat should be resistant to enamel and lacquer thinners. The trouble is, a clear acrylic with hardener, or a catalyzed urethane clear will also likely be resistant to these solvents.

WB ......... metalworking projects

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Reply to
Wild_Bill

I had a fiberglass boat clear coated and now, ten years later, the clear coat is coming off due, I believe, to UV damage.

It looks almost exactly like someone that got badly sunburned with large pieces of sort of wrinkled "skin" peeling off in some areas and what appears to be undamaged paint in others.

Bad gelcoat usually appears to be crazed with exceptionally bad cases showing chunks and chips falling out.

Bruce in Bangkok (brucepaigeatgmaildotcom)

Reply to
Bruce

BINGO! That is exactly what it looks like!

-Carl

Reply to
Carl Byrns

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