Sunshine and blisters

Feb 11, 2014
43
Beneteau 40 cc Oceania Central Point
Hi all newest of the new. Blisters on the out side of the cabin, we turned the boat around yesterday,now the side in the sun is showing blisters,moisture meter 11.5. 1997 beneteau 40 cc. In Tampa bay
image.jpg
image.jpg
 
Sep 25, 2008
7,075
Alden 50 Sarasota, Florida
There are lots of boats in the Florida sun without that malady. Whatever is causing that is unrelated.

Is it a re=painted topsides or original gel??
 
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Feb 11, 2014
43
Beneteau 40 cc Oceania Central Point
Looks like original gel. thank you for your time to look.
 
Feb 11, 2014
43
Beneteau 40 cc Oceania Central Point
one more observation I cannot detect a vinegar oder.
 
Jan 11, 2014
11,321
Sabre 362 113 Fair Haven, NY
Painted surfaces that are covered with a tarp, shrink wrap, or plastic will blister. The overspray on the top of the ports leads me to believe the cabin top was painted. Another possibility is the cabin top was not dry when it was painted and moisture is coming out of the laminate when it is in the sun.

I don't think it is the same as blistering below the water line. Those blisters need some hydrostatic pressure to get the water past the gelcoat and into the laminate.
 
Sep 25, 2008
7,075
Alden 50 Sarasota, Florida
Looks like original gel. thank you for your time to look.
The pictures appear to show it is paint. Gel is porous and typically won’t delaminate like that.

Regardless, you have a project on your hands now, the first step being to definitively determine what we are looking at.
 
Feb 11, 2014
43
Beneteau 40 cc Oceania Central Point
Thank you, best way to determine paint or gel coat would be.
 
Jun 25, 2004
1,108
Corsair F24 Mk1 003 San Francisco Bay, CA
Thank you, best way to determine paint or gel coat would be.
Thickness will tell.
Gelcoat will be about 15-25 mil thick. Cured 2part paint will be 3-5 mil thick. I don't remember how thick 1 part paint would be bcuz I haven’t used it in 20 +years.

I wonder if it could be something weird like a polymer clear coat or Polyglow. Either way, it isn’t adhering to the substrate, so it will have to be stripped off.

Maybe you could peel of one of the blisters and take a look at the thickness and color and transparency.
 
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TomY

Alden Forum Moderator
Jun 22, 2004
2,758
Alden 38' Challenger yawl Rockport Harbor
Thickness will tell.
Gelcoat will be about 15-25 mil thick. Cured 2part paint will be 3-5 mil thick. I don't remember how thick 1 part paint would be bcuz I haven’t used it in 20 +years.

I wonder if it could be something weird like a polymer clear coat or Polyglow. Either way, it isn’t adhering to the substrate, so it will have to be stripped off.

Maybe you could peel of one of the blisters and take a look at the thickness and color and transparency.
That's what I was thinking: Paint is thin, gel coat is not. Be fearless, pop one,...
 

dLj

.
Mar 23, 2017
3,372
Belliure 41 Sailing back to the Chesapeake
Thickness will tell.
Gelcoat will be about 15-25 mil thick. Cured 2part paint will be 3-5 mil thick. I don't remember how thick 1 part paint would be bcuz I haven’t used it in 20 +years.
Paint thickness will typically fall at a Max thickness you've stated, usually about half that but it depends. They also could have put on more than one coat.

@DrJudyB is spot on, open up one of the blisters and look at the thickness. Gel coat will be thick, paint would be thin. The appearance of what I see in your photos looks like paint to me. But hard to tell from here...

dj
 

Ward H

.
Nov 7, 2011
3,645
Catalina 30 Mk II Barnegat, NJ
@Stratus3 I can’t help with your question but I love your avatar photo. Your pup looks very dignified.