Blistering

SunnySideUp · #1 (**permalink**) 06-20-2006

Good day all,

I have 1981 22' Catalina that has been in the water most of her life. You all know what that means BLISTERING. I have to get her out of the water to do some other work on her, knowing that she will have blistering I 'll need to fix that along with the other work. My question is what is the best path to take when it comes to blistering. I would like to do the work my self and have a few insights on what to do, but would like a few more just to make sure I'm going the right way. My first step will be to have her surveyed.

sailingdog · #2 (**permalink**) 06-20-2006

Depends on how deep the blisters go. If they are mostly superficial, and in the gelcoat, then sanding, letting the hull dry and then re-fair and epoxy barrier coating is probably the way to go. If the blisters go deeper into the laminate, then you'll have a lot of nasty work cut out for you...not that blisters aren't nasty to begin with.

pigslo · #3 (**permalink**) 06-21-2006

I Interlux barrier coated my boat and after a year no blisters had returned. Don Casey's book gives a detailed description of how to treat the blisters. It is not that difficult.

pigslo

SunnySideUp · #4 (**permalink**) 06-21-2006

What is the name of Don Casey book so that I may check it out.

RichH · #5 (**permalink**) 06-21-2006

For probably the best blister information and help in deciding exactly what to do, go to: www.yachsurvey.com and follow the links to "blisters".

Faster · #6 (**permalink**) 06-21-2006

Treating the blister problem is a relatively simple procedure and you'll get plenty of advice from links like the above.
The biggest part of the procedure, and one that probably gets short-circuited the most is the drying out of the hull once the blisters have been opened up. This can take literally months, up to 6 or more. A good way to address this is to write off the latter part of the season, haul in the fall, seal off the boat in a tarp or shelter of some sort and keep it dry and warm over the winter. Then address the repairs in the late spring.

We did just that a few years back on a 1981 boat, used Interlux barrier epoxy, laid on 6 - 8 coats, and have not had a recurrence .

pigslo · #7 (**permalink**) 06-21-2006

Yes the drying of the hull is important. More of an issue in the northern climates. Mine dryed in a metal warehouse in Houston in the summer. It was there for 2 years. Hard to beat that. There are ways to hasten the process up north with lights and what have you.

pigslo

sailingdog · #8 (**permalink**) 06-21-2006

Yes, making sure the laminate is completely dry is the most important part of repairing blistering. Unfortunately, the only easy way to do that is TIME, hot dry air, and patience.

Gary M · #9 (**permalink**) 06-21-2006

The link above would not open but it sounds like people are saying you can just open up the known blisters dry out and and then epoxy.
In my experience you should take off all of the gel coat and then dry the hull. There will be internal blisters trapped within the gel coat that have not appreared yet.
On a 22 ft boat it is not that big a job to remove it all. I just completed a 30 footer and that was fun.
I found a powerful ( 3 amps) random obital sander to be the best method.

Gary

SunnySideUp · #10 (**permalink**) 06-21-2006

If there is one thing I have it is time. My job is taking me away for three mouth,(three of the hottest mouths in GA.) I'm just wondering if I should open the blister before I go away or wait till I get back. I can always do the other work over the winter and let the blister wait till spring.