Stus-List Re: [EXTERNAL] Cored hulls feedback wanted

[Della Barba, Joe via CnC-List]

You are combining two issues.

  1.  Is the boat sound now? A good surveyor is the key to this. All these 
boats are old and all can have issues, cored or not cored.
  2.  Damage from reefs and rocks. At the point the hull has holes in it, the 
boat is in bad shape regardless and will need to be hauled and repaired if that 
is even possible. Sure the core will need replacing in the damaged areas, but 
that will be the least of your problems. End-grain balsa does not let water 
spread easily, so it isn’t like the whole core is saturated in a day.
I would not hesitate to sail a cored boat because of potential damage from 
collisions. My uncored boat would be totaled pretty quickly if she were holed 
on a reef with waves washing over. If I could get loose and patch a minor hole, 
I could also get loose and patch a hole in a cored hull too.

Joe Della Barba
Coquina


From: Shawn Wright via CnC-List 
Sent: Monday, March 20, 2023 7:06 PM
To: Stus-List 
Cc: Shawn Wright 
Subject: [EXTERNAL] Stus-List Cored hulls feedback wanted

As we once again consider a boat with cored hull (LF43 or LF38), I am reminded 
of why we eventually chose our current 35 four years ago. I couldn't be sure of 
the hull integrity without an expensive survey, and at the low price range we 
could afford, avoiding a cored hull just removed this concern.

But as I understand it, most C&Cs over 35' have been cored since the late 60s 
or early 70s depending on the model, so that includes a lot of boats, most of 
which are probably still sailing, albeit mainly coastal cruising or racing. Now 
as we consider the next boat for our long term offshore boat, things like 
potential hull damage from a reef or a collision in a remote part of the world 
are a concern.

So I am interested in hearing about experiences with cored C&Cs, problem which 
have occurred under both normal use and as a result of damage from impact, and 
how effectively they could be repaired.

I guess an additional question is how C&C's balsa coring compares with modern 
day foam coring, either with or without vacuum bagging. I assume foam has some 
advantages in not absorbing water.

Thanks.
--
Shawn Wright
shawngwri...@gmail.com
S/V Callisto, 1974 C&C 35
https://www.facebook.com/SVCallisto
Please show your appreciation for this list and the Photo Album site and help 
me pay the associated bills.  Make a contribution at:
https://www.paypal.me/stumurray
Thanks for your help.
Stu

Stus-List Re: Cored hulls feedback wanted

[Matt Wolford via CnC-List]

Shawn:

 

My 42 Custom is a “stick boat,” not a production boat, so 
results will vary.  In my case, I basically saved the boat from the landfill. I 
bought her without a hull survey because the seller’s rep (an Estate sale) is 
an old friend of mine, very knowledgeable about boats (he repairs them for a 
living), and knew this boat in particular.  He showed me an area where he made 
a hull repair, and advised that the rest of the boat was sound.  Based on his 
representation, I decided to proceed with the purchase.  I needed a hull survey 
to satisfy the insurance company, and the surveyor picked up a wet spot on the 
port side behind the keel.  The affected area was about 3’ x 3’ and accessible 
from the inside – no big deal.  I then asked my boat guru to have a look.  He 
metered the boat and called me to say we “needed to have lunch.”  He explained 
during lunch that the core below the waterline was wet from the keel to the 
rudder, and the repair (done correctly) would take time and be expensive.  
After fixing that problem (on the hard for a year), we then discovered that the 
core was also wet from the keel forward to the bow.  Another lost season.  
(Moisture detection up front was masked by a really thick layup of fiberglass 
that you might not see in a production boat.)  After fixing that problem, 
followed by about 12 coats of barrier coat, all was good for a few years.  Then 
I noticed some blistering amidships on both sides (the only places left).  
Water intrusion from the inside was impossible due to the barrier coat, and we 
concluded that decades of condensation under the water tanks likely caused the 
problem.  I addressed the port and starboard sides one year at a time to avoid 
disrupting the sailing season.  The port side repair required removing a water 
tank.  The starboard side repair required removing the second water tank and 
the fuel tank.  Everything is fixed, and the boat is probably stronger now than 
when it was built.  However, it took a lot of work, patience, money, and West 
System.

 

The moral of the story: don’t even think about buying a boat 
with a cored hull below the waterline unless you’re completely comfortable 
after hearing from a surveyor who really knows how to use a moisture meter.

 

Matt

 

From: Shawn Wright via CnC-List  
Sent: Monday, March 20, 2023 7:06 PM
To: Stus-List 
Cc: Shawn Wright 
Subject: Stus-List Cored hulls feedback wanted

 

As we once again consider a boat with cored hull (LF43 or LF38), I am reminded 
of why we eventually chose our current 35 four years ago. I couldn't be sure of 
the hull integrity without an expensive survey, and at the low price range we 
could afford, avoiding a cored hull just removed this concern. 

 

But as I understand it, most C&Cs over 35' have been cored since the late 60s 
or early 70s depending on the model, so that includes a lot of boats, most of 
which are probably still sailing, albeit mainly coastal cruising or racing. Now 
as we consider the next boat for our long term offshore boat, things like 
potential hull damage from a reef or a collision in a remote part of the world 
are a concern. 

 

So I am interested in hearing about experiences with cored C&Cs, problem which 
have occurred under both normal use and as a result of damage from impact, and 
how effectively they could be repaired.

 

I guess an additional question is how C&C's balsa coring compares with modern 
day foam coring, either with or without vacuum bagging. I assume foam has some 
advantages in not absorbing water.

 

Thanks. 


--

Shawn Wright

shawngwri...@gmail.com  

S/V Callisto, 1974 C&C 35

https://www.facebook.com/SVCallisto

Please show your appreciation for this list and the Photo Album site and help 
me pay the associated bills.  Make a contribution at:
https://www.paypal.me/stumurray
Thanks for your help.
Stu