[C320-list] Anti Blister protection

[Allan Field]

Stephane - Blisters, as I understand them, are caused by the inevitable
migration (think osmosis) of water into the hull where the water reacts with
the resins (polyester?) that used to be used in layup.  This reaction
created an acid which then ate its way back out.   Once you actually see a
blister, the internal damage has been done.  That said, there is no case on
record of a boat sinking due to blisters, at least as of about 6-7 years
ago.

The hull on the Catalina is laid up with vinylester resin from rubrail to
rubrail; most production boats now use vinylester from waterline to
waterline so kudos to Catalina.  Water migrating into the hull does not
react with vinylester resin to create an acid thus supposedly no blisters.
According to Gerry Douglas, Catalina designer, there have been a very few
cases of very minor blistering with Catalina's but none in the past few
years.  That said, I am not sure why Catalina's hull warranty is only 5
years and pro-rated per year at that.  Regardless, after having gone through
an 8K complete peel down and re-layup on my previous boat, I am particularly
sensitive to this issue.  At the end of the day, I have decided to trust
Gerry and not go through the time and expense of doing a barrier coat.
Seems to me it would be akin to wearing a belt with suspenders.  Just my
thoughts...

According to informed but anonymous sources, the only boat that Catalina
ever made with non-vinylester layup was sold to a woman in the San Francisco
Bay area who bought it for her boy-toy.  But this may just be another urban
legend...

Allan S. Field
Sea Shadow - #808
Columbia, MD

-----Original Message-----
From: c320-list-bounces at catalina320.com
[mailto:c320-list-bounces at catalina320.com] On Behalf Of Stephane Rousseau
Sent: Wednesday, January 17, 2007 3:14 PM
To: c320-list at catalina320.com
Subject: [C320-list] Anti Blister protection

Hello,

I have a Catalina 320 1998, this year, I have remove all the antifouling on
the bottom. It can be a good time to make an antiblister protection
(Interprotec). I know that some boats and years need it. Does Catalina320
boat need this protection to be added?

Thank

Stephane