blisters above water line?

[markarbor]

Well i have finally bought a 222 to restore. While i was striping all of the old parts off i notice blister like bumps on the outside of the hull. They are above the waterline. They are hard when i press on them. They do not appear to have any water in them. i am concerned about them, what caused? If i sand them out i will have to fill and fair. Could they com back in the same places or maybe in other areas? i would hate to go though all of this work restoring and battle these thing. Anyone have any experiance with these? thanks

[Aland]

I have seen this in the past, I think you can just sand them smooth. Do you have the liner out to see the other side of the hull? Post some pics.

[Capt. Bob]

Not the first time we've seen this.
http://classicaquasport.com/smf/index.php?topic=8104.15

Third paragraph from bottom, first post.
http://classicaquasport.com/smf/index.php?topic=379.0

Scroll down to third pic in this post.
http://classicaquasport.com/smf/index.php?topic=9164.msg80772#msg80772

This is to show you that while not a rampant disease in Aqua hulls, it is an occurrence in fiberglass and appears fixable enough. Hopefully others will chime in.

Good luck.

[CLM65]

How many blisters are we talking about?  Personally I would probably grind them out and repair with VE and CSM, assuming they weren't too numerous and big.  I highly doubt they would come back.

[markarbor]

This is what i have. Please let me know any options. I am unsure about these "blister". if i fix could there be an on going problem? What is the best way to fix them?  This will already add a lot of work to my rebuild. But this is my dream boat.

[markarbor]

This is the worst area but it does go down each side, they are smaller in the other areas. seems to stop where the bow rises.

[markarbor]

...

[fitz73222]

Blisters are common on the bottom of boats kept in the water and it's typically water absorption through the gelcoat over time and the eruptions occur and when popped they usually have a mixture of water and remnant smell of fiberglass. Why they occur on the gunnels of our boats is still a mystery. They are typically dry and almost seem to show up overnight. The common denominator seems to be in the 70's model hulls, kept outside uncovered but no one seems to know why. We know that gelcoat shrinks after 40 years and starts to craze and crack, all boats do it in time when in the elements, I'll assume UV damage and thermal cycling as root cause, but these blisters seem to be firmly attached. The only explanation may be that this is a result of the core gassing off and forming these things after some reaction to time, elements, and some chemical or mechanical circumstances. It would be unnerving to just grind them off in the effected areas, sand, prep and paint only to have them potentially reappear in a previously uneffected area. My advice is seek out information as to why they occur from someone in the boat business or some engineering explanation that makes sense before prepping this boat for paint. That's what I would do if it was mine.

[fitz73222]

Thinking this further through, one thing I have noticed from past posts about this issue is it seems to be prevalent on boats that have bottom paint on them. If it is exclusive and not related to being in the water, is it possible that it is a longer term reaction between the chemicals in bottom paint and the resins in the fiberglass? But then why show up on the vertical surfaces and not the bottom also? There has to be some science to this and we just need to figure out why?

[Woodeneye]

.....has that been painted??? it doesn't look like original gel coat??
In any case if you prick one of the blisters and it has a dark slightly acrid smelling dark liquid oozing from it you may have yourself some osmosis. If not you may just have some blisters in paint. Either way there are procedures to deal with it. Hope for paint blisters.

[markarbor]

Nothing inside of these. There is not any fluid. I am not sure if it has been repainted but it appears to be original. I don't think they are paint blister. I was hoping for that. But they are solid, no  give at all when we I press on them. I have talked to a guy who does amazing work on these boats here in Sarasota. He described removing the gel and first layer of mat. Re glassing re gelling. Sound like the best method . But also sounds expensive as to I am not the best at finish work.bi am at a loss I have been looking for one for years finally pulled the trigger and now I'm not sure if it's worth it.

[RickK]

My  ,
If you like the boat and it fulfills what you need in a boat I would plan on repainting the hull. That being said I would take a grinder to it, see what's there.  From here, it does look like gelcoat and not paint.  Once you're into it you can fill the blemishes, fair it out and paint.  There is a young fella in Venice or south a bit that does great work if you can't handle it.  Here is a thread for an example of his work - PM the owner for details.
http://classicaquasport.com/smf/index.php?topic=8458.0

[jerryh3]

My 1972 22-2 has that also.  Not quite that bad.  But, it's down both sides of the hull

[jerryh3]

[RickK]

Looks like you have some work ahead of you.