Answer 2 to Halpin family


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Posted by Bengt Blomberg on May 31, 2000 at 16:31:36:


This kind of work so far can only be performed by two of the HYAB organisation people when it comes to this size of hull. An
HYAB Operator must have experience from a substantial number of smaller hulls before being let alone
with a bigger one.
This was the reason for the question where the hull is situated (geografically).
Regarding your comments:
The dangerous phthallic acid is not water soluble. It is dissolved in glycol and or styrene and totally encapsuled within proper
polyester, which can not be penetrated by any kind of "wash" liquid without making the polyester plastic by heat. As the hull
has already had a "protective" coating for some time and also showed some blisters there will positively be quite a lot of such
acid enclosures which in due time will cause or have already caused delaminations in the laminate. To just dry the foam and
apply any number of "protective" coating has no meaning.
Gelcoat, epoxy or vinyl ester are all absorbing materials. The two later absorbs very much less than the gelcoat or the polyester
laminate. However that does not say anything about how much water that can be pressed through due to the weight of the
hull!! If you pour some water on a table and lays a coffe filter in that water, the filter will absorb a certain amount and then no
more. If you instead pours water into the open filter, due to the weight of the water any amount will pass through. If you use a
more solid paper, it will absorb less but you can pour any amount through it even if it will take some more time.
A "protective" coating will just delay a new total soaking of the foam one or two months.

Now, the most severe problem in your case is much worse! The foam is an important stabilizing part of the construction which
is now destroyed. The bottom of the hull will sway far too much at planing speeds even in moderate seas. Without a repair
which creates sufficient new support there is high risk that the laminate breaks.

If you want to use the boat in the mean time I recommend deplacement speeds only. In order to delay hydrolysis damages as
much as possible you should then apply a one component primer and antifouling only until a proper repair can be performed.
Such a repair will probably cost more than the to-day value of the boat, but afterwards at
least the hull will be much better than a 20 years younger boat and if you are doing substantial boating you will find, that the
difference in fuel consumption will pay for the repair in a few years.



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