Cored Hulls and Decks - Page 3 - SailNet Community
Reply
 
LinkBack Thread Tools
post #21 of 59 Old 10-18-2010
Telstar 28
 
sailingdog's Avatar
 
Join Date: Mar 2006
Location: New England
Posts: 43,290
Thanks: 0
Thanked 16 Times in 13 Posts
Rep Power: 14
         
You've never seen cruisingdad sail, have you???
Quote:
Originally Posted by mitiempo View Post
If you run aground the keel should touch, not the hull. If the hull touches you are really aground.

Sailingdog

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Telstar 28
New England

You know what the first rule of sailing is? ...Love. You can learn all the math in the 'verse, but you take
a boat to the sea you don't love, she'll shake you off just as sure as the turning of the worlds. Love keeps
her going when she oughta fall down, tells you she's hurting 'fore she keens. Makes her a home.

—Cpt. Mal Reynolds, Serenity (edited)

If you're new to the Sailnet Forums... please read this
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
.

Still—DON'T READ THAT POST AGAIN.
sailingdog is offline  
Quote Quick Reply Share with Facebook
Sponsored Links
Advertisement
 
post #22 of 59 Old 10-18-2010
Senior Member
 
djodenda's Avatar
 
Join Date: Mar 2006
Location: Kirkland, Washington
Posts: 1,795
Thanks: 1
Thanked 8 Times in 8 Posts
Rep Power: 11
   
My CS 36 Merlin is balsa cored above the waterline. (Vacuum bagged, actually)

A nice thing I noticed this summer was that the boat warmed up quite a bit faster than my old C30 did when I turned the heater/stove on.

I am assuming that the added insulation of the balsa coring was the reason for this. Certainly made the boat more comfortable.

Two footnotes:

1) Yes, I was running the heater in the middle of the summer in the San Juans.
2) Wombat: It only took me a year to find a new boat. How long is it gonna take you?

David

David

1987 CS 36 Merlin "Kyrie"

"They drove a dump truck full of money up to my house. I'm not made of stone!" -Krusty the Clown

Last edited by djodenda; 10-18-2010 at 06:26 PM.
djodenda is offline  
Quote Quick Reply Share with Facebook
post #23 of 59 Old 10-18-2010 Thread Starter
tdw
Super Fuzzy Moderator
 
tdw's Avatar
 
Join Date: Oct 2006
Location: Sydney Australia
Posts: 16,956
Thanks: 20
Thanked 121 Times in 112 Posts
Rep Power: 10
     
hee hee.....I should stick to debating guns....

Thanks you all for the input.

Not that I am in any way less confused than before but I think the reality is that cored is not necesssarily the road to hell though should one stray from the straight and narrow, knee deep doodoo may be your reward.

Someone...you know who you are djodenda....suggests that this search for the new Womboat has been going on for too long. He'd be right. Were it not for the fact that we have a fine little craft to get us by, I dare say I'd have gone completely (as distinct from partially) loopy by now. As I remarked in reply to a message on this subject were it possible for me to move to Europe or the US for a few months it would probably be all done and dusted by now. Unfortunately the pool of available craft in Australia is not large and the actual design that I most lust after is seemingly highly prized internationally. There have been a couple of examples for sale in Europe this year but both sold before we could have possible organised to fly to Europe. So when something appears on the Oz market that is a possibility , for better or worse a cored hull possibility, questions must be asked.

Thanks again.

Andrew B (Malö 39 Classic)

“Life is a trick, and you get one chance to learn it.”
― Terry Pratchett.

Last edited by tdw; 10-19-2010 at 05:08 PM.
tdw is online now  
Quote Quick Reply Share with Facebook
post #24 of 59 Old 10-19-2010
ASA and PSIA Instructor
 
Join Date: Apr 2000
Posts: 3,649
Thanks: 10
Thanked 27 Times in 27 Posts
Rep Power: 16
 
Quote:
Originally Posted by mitiempo View Post
If you run aground the keel should touch, not the hull. If the hull touches you are really aground.
Although there are a variety of scenarios by which water can get into the hull core (a set screw for an owner-installed bilge pump being my favorite), the big concern I have with cored hulls is a hard grounding. The real risk from a hard grounding is that the impact will crack the exterior laminate. As the back end of the keel is levered up the surrounding laminate flexes, and in some circumstances enough to produce a crack in the outer skin, exposing the core to water intrusion. By the time the the boat is subesquently pulled, the entire hull core is wet, and the only fix is to peel and replace.

Now I would hope some manufacturers having used core for a while have engineered in some cushion to prevent this predictable problem, so I can't comment on the newest boats. But I can say there are models built in the late '70s thru the '80s, which have demonstrated that hitting a rock at 6 knots creates a problem whose proper repair will cost the owner $10-20,000. Who needs it?

Certified...in several regards...
sailingfool is offline  
Quote Quick Reply Share with Facebook
post #25 of 59 Old 10-19-2010
Senior Member
 
tommays's Avatar
 
Join Date: Sep 2008
Posts: 4,299
Thanks: 1
Thanked 31 Times in 31 Posts
Rep Power: 8
 


Well

I would love to say a solid hull did fine BUT that was NOT the case This 1970 C&C 35 had custom keel that was wraped and glassed and the hull was BEEFED-UP to take the new loads (naval architect no DIY)


The keel to hull joint did not even chip the piant BUT the hull failed about 2' behind the keel and it was a HUGE repiar

1970 Cal 29 Sea Fever

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

1981 J24 Tangent 2930
Tommays
Northport NY


If a dirty bottom slows you down what do you think it does to your boat
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
tommays is offline  
Quote Quick Reply Share with Facebook
post #26 of 59 Old 10-19-2010 Thread Starter
tdw
Super Fuzzy Moderator
 
tdw's Avatar
 
Join Date: Oct 2006
Location: Sydney Australia
Posts: 16,956
Thanks: 20
Thanked 121 Times in 112 Posts
Rep Power: 10
     
Quote:
Originally Posted by tommays View Post


Well

I would love to say a solid hull did fine BUT that was NOT the case This 1970 C&C 35 had custom keel that was wraped and glassed and the hull was BEEFED-UP to take the new loads (naval architect no DIY)


The keel to hull joint did not even chip the piant BUT the hull failed about 2' behind the keel and it was a HUGE repiar
Tom,
I saw this pic in another thread and meant toask you then. What exactly are we looking at ? I don't get it. Did she run aground and that is the damage shown or am I missing something ?

Andrew B (Malö 39 Classic)

“Life is a trick, and you get one chance to learn it.”
― Terry Pratchett.
tdw is online now  
Quote Quick Reply Share with Facebook
post #27 of 59 Old 10-19-2010
Telstar 28
 
sailingdog's Avatar
 
Join Date: Mar 2006
Location: New England
Posts: 43,290
Thanks: 0
Thanked 16 Times in 13 Posts
Rep Power: 14
         
Quote:
Originally Posted by tdw View Post
Tom,
I saw this pic in another thread and meant toask you then. What exactly are we looking at ? I don't get it. Did she run aground and that is the damage shown or am I missing something ?
that's where the keel hit...he doesn't appear to have a photo of where the hull was torn from this impact.

Sailingdog

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Telstar 28
New England

You know what the first rule of sailing is? ...Love. You can learn all the math in the 'verse, but you take
a boat to the sea you don't love, she'll shake you off just as sure as the turning of the worlds. Love keeps
her going when she oughta fall down, tells you she's hurting 'fore she keens. Makes her a home.

—Cpt. Mal Reynolds, Serenity (edited)

If you're new to the Sailnet Forums... please read this
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
.

Still—DON'T READ THAT POST AGAIN.
sailingdog is offline  
Quote Quick Reply Share with Facebook
post #28 of 59 Old 10-19-2010
Senior Member
 
mitiempo's Avatar
 
Join Date: Sep 2008
Location: Victoria B.C. Canada
Posts: 7,667
Thanks: 0
Thanked 102 Times in 93 Posts
Rep Power: 9
   
An external lead keel is preferred when hitting rocks. Doesn't do much for the damage to the hull at the aft end of the keel though.

Brian
Living aboard in Victoria Harbour
mitiempo is offline  
Quote Quick Reply Share with Facebook
post #29 of 59 Old 10-19-2010
Senior Member
 
tommays's Avatar
 
Join Date: Sep 2008
Posts: 4,299
Thanks: 1
Thanked 31 Times in 31 Posts
Rep Power: 8
 




looks worse than it was


big area of damage at the blue paint well behind the keel

Its the LEAD keel on Zzzoom which dinged a rock at 7 knots healed at about 15 degrees

When the PO owned the boat he hired Britton Chance to do several keels a modern double spreader rig and rudder years back

The C&C 35 I has no sump or bilge to speak of for that matter

The new keel was much deeper 7' and a shorter mounting footprint so to take the load and support the mast which NO longer had the BIG original keel under it

They really beefed up the hull and it never had and issues with the smile UNTIL the rock and it had no smile after the rock

The lead did not yield at the hull at ALL

Small amount of hull damage forward and aft of the keel

Massive damage 2' behind the keel were the hull was finally weak enough to yield to the massive force involved


I have another friend with a Tartan 372 that hit a ledge in Maine and in the finest mythbusters BUSTING myths it broke all kinds of stuff on the boat like all 4 motor mounts

I assure running aground is NOTHING like hitting a unyielding rock and lead or cast iron your screwed and the boat is NOT gonna be OK

1970 Cal 29 Sea Fever

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

1981 J24 Tangent 2930
Tommays
Northport NY


If a dirty bottom slows you down what do you think it does to your boat
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Last edited by tommays; 10-19-2010 at 08:06 PM.
tommays is offline  
Quote Quick Reply Share with Facebook
post #30 of 59 Old 10-19-2010
ASA and PSIA Instructor
 
Join Date: Apr 2000
Posts: 3,649
Thanks: 10
Thanked 27 Times in 27 Posts
Rep Power: 16
 
Quote:
Originally Posted by tommays View Post

....
I assure running aground is NOTHING like hitting a unyielding rock and lead or cast iron your screwed and the boat is NOT gonna be OK
I have to disagree...I have hit rock hard four times that I remember the past thirty years and never had a repair beyond filling the divot hole in the lead. Some boats are better designed to take abuse and just keep ticking, some less, its all a set of tradeoffs. But you can enjoy a good performing boat and still have it be able to take a beating.

Certified...in several regards...
sailingfool is offline  
Quote Quick Reply Share with Facebook
Reply

Quick Reply
Message:
Options

By choosing to post the reply above you agree to the rules you agreed to when joining Sailnet.
Click Here to view those rules.

Register Now



In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.


User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Similar Threads
Thread Thread Starter Forum Replies Last Post
Cored Hulls Up North? redstripesailor Living Aboard 5 07-31-2008 02:16 AM
Cored hulls and logs ArgleBargle Boat Review and Purchase Forum 1 05-04-2007 03:29 PM
Airex Cored Decks CBinVA Boat Review and Purchase Forum 4 08-06-2006 11:07 PM
Are Col hulls cored? mrb2222 Boat Review and Purchase Forum 4 01-08-2002 04:59 AM
Cored Hulls Jon Shattuck Gear and Maintenance Articles 0 10-03-2000 09:00 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome