Hi,

I hope it is OK to ask a repair question here.


I have a friend who is considering buying a boat, and has asked me to give
"expert" advice. We are looking at an Andersson-23 (English, heavy GRP
construction from the early 80's). It does look acceptable for the low
price, except for one detail, which I can not judge.

On the side, well above the waterline, there is an old scar, about the size
of a fingerprint. Around that are fine hairline cracks in a circular
pattern, something line 15 cm (6") wide. I suspect there has been some sort
of impact damage, the gel coat was damaged, and water has started to enter.

I am wondering how seriously I should worry about this blister? Will it sink
the boat this summer? Will it get worse and worse, and destroy the whole
boat in a few years? Or can I treat it as a cosmetic problem, and sail
happily for years without worrying about it?

We have got the boat offered at a pretty low price from the previous owner
(family of my friend) whose wife don't like sailing. The boat has not been
in water last season, and seen pretty little use the season before that.
The owner does not remember seeing this scar before, so it may be a new
development (the boat has been moved around a few times during the last two
years, further and further back on the winter storage area).

Any serious comments would be appreciated

Heikki Levanto
Copenhagen, Denmark

Nice to see you in here ol' buddy
Deep down, all real men are sailors!

I'm working on converting a 28' GRP fishing cutter right now.
As long as the star is well above watermark, don't worry. It will not
drink
water to worry about, unless you go for serious deep water sailing.
You can fix it when it is hauled out of the water in the autumn.
As for repair I would say grind it down, so all the pattern is gone, and
get
as deep as you can at the impact itself - you'l probly find the center
delaminated and crushed.
then again build up with mat and polyester, so all cracks are sealed.
And recoat.

See you
Ole

"Heikki" skrev i en meddelelse
. ..
Hi,

I hope it is OK to ask a repair question here.


I have a friend who is considering buying a boat, and has asked me to
give
"expert" advice. We are looking at an Andersson-23 (English, heavy GRP
construction from the early 80's). It does look acceptable for the low
price, except for one detail, which I can not judge.

On the side, well above the waterline, there is an old scar, about the
size
of a fingerprint. Around that are fine hairline cracks in a circular
pattern, something line 15 cm (6") wide. I suspect there has been some
sort
of impact damage, the gel coat was damaged, and water has started to
enter.

I am wondering how seriously I should worry about this blister? Will it
sink
the boat this summer? Will it get worse and worse, and destroy the whole
boat in a few years? Or can I treat it as a cosmetic problem, and sail
happily for years without worrying about it?

We have got the boat offered at a pretty low price from the previous
owner
(family of my friend) whose wife don't like sailing. The boat has not
been
in water last season, and seen pretty little use the season before that.
The owner does not remember seeing this scar before, so it may be a new
development (the boat has been moved around a few times during the last
two
years, further and further back on the winter storage area).

Any serious comments would be appreciated

Heikki Levanto
Copenhagen, Denmark

Heikki writes:

On the side, well above the waterline, there is an old scar, about the size
of a fingerprint. Around that are fine hairline cracks in a circular
pattern, something line 15 cm (6") wide. I suspect there has been some sort
of impact damage, the gel coat was damaged, and water has started to enter.

I am wondering how seriously I should worry about this blister? Will it sink
the boat this summer? Will it get worse and worse, and destroy the whole
boat in a few years? Or can I treat it as a cosmetic problem, and sail
happily for years without worrying about it?

Any signs of damage on the inside of the laminate?
Have you probed the damage? Tip of sharp knife trying to pry open
gelcoat would yield some information. Tapping the area and listening
would tell you if there is a void or serious delamination. A more
subtle damage calls for ultrasonic instruments to assess.

If the laminate looks ok from the inside and sounds solid when tapped
you won't sink this summer. I ended a season many years ago sailing
around with patch of silver-grey tape over hole in the starboard hull.
The hole was not under the water :-)

--
================================================== ======================
Martin Schöön

"Problems worthy of attack
prove their worth by hitting back"
Piet Hein
================================================== ======================

Schöön Martin wrote:

Heikki writes:

On the side, well above the waterline, there is an old scar, about the size
of a fingerprint. Around that are fine hairline cracks in a circular
pattern, something line 15 cm (6") wide. I suspect there has been some sort
of impact damage, the gel coat was damaged, and water has started to enter.

I am wondering how seriously I should worry about this blister? Will it sink
the boat this summer? Will it get worse and worse, and destroy the whole
boat in a few years? Or can I treat it as a cosmetic problem, and sail
happily for years without worrying about it?

Any signs of damage on the inside of the laminate?
Have you probed the damage? Tip of sharp knife trying to pry open
gelcoat would yield some information. Tapping the area and listening
would tell you if there is a void or serious delamination. A more
subtle damage calls for ultrasonic instruments to assess.

If the laminate looks ok from the inside and sounds solid when tapped
you won't sink this summer. I ended a season many years ago sailing
around with patch of silver-grey tape over hole in the starboard hull.
The hole was not under the water :-)

----------

you might consider 'sealing' the hairline cracks from moisture and air with Capt
Tolley's creeping crack sealer - available in just about all the big marine
catalog stores.

paul oman

This does not sound like a problem at all. Most older boats have
similar impact marks that go only through the gel-coat and not into the
underlying glass. Hit the corner of a dock a little harder than you
expect and suddenly you have another. Buy the boat and dont worry
about it.

wrote:

This does not sound like a problem at all. Most older boats have
similar impact marks that go only through the gel-coat and not into the
underlying glass. Hit the corner of a dock a little harder than you
expect and suddenly you have another. Buy the boat and dont worry
about it.

Thanks everyone for the advice. I'll go and buy the boat, and don't worry
about this blister at least for this season. Next year I'll see if I want
to do anything about it. Meanwhile I will have found out what the real
problems are...

-Heikki