Hull Hard Spot leading to Interior Refit

[Blueskyzephyr]

HelloAll,

I noticed a 3 inch vertical crack where my port main bulkhead meets the hull. This set of bulkheads also supports my deck stepped mast. I understand that excessive rigging tensions could cause such a condition, but I do not believe that I set my rigging anywhere near drum tight so I am interested in hearing what other contributing factors could have contributed to this cracking.

I am comfortable with the repair of the actual crack, much reference material is out there. I plan on reinforcing a broad area on the inside of the hull to ensure the exterior repair is stable. I also plan on reinforcing the sections under the other new bulkheads that I will be fabricating.

I plan on rebuilding the entire cabin, from a bare hull interior. The bulkheads are soft.
I would appriciate suggestions that would strengthen my boat overall.

Some of my initial considerations include 2 longitudal stringers that would tie in to the bulkheads as well as compression posts near the compainionway. I also plan on having laminating stiffeners into the large unsupported V berth area fiberglass bow section.

I am working with the titles Form a Bare Hull, as well as Boat Interior Construction. I Am looking to pick up Spurrs Guide to Upgrading your sailboat, as well as Gerr's Elements of Boat strength. Thank you Sailnet community for any input and advice that is given.

Sincerely, Mike

[chris_gee]

It might help to know the boat (well a bit) like is all that effort worth it. The bulkheads I would not expect to be soft ie rot unless water was getting at them. From where I would ask.
I would think that the books you cite would be a big help but I was under the impression that a hull hard spot led to flexing and strain adjacent to it, but a vertical crack suggests it is not that but perhaps working of the hull around bulkheads that were not adequately tabbed or were rotten.

[sailingdog]

Bluesky-

It would help if you said what make/model of boat you're having the problem on. In many cases, certain issues are known to be a problem for certain boats, like the Catalina smile with their hull/keel join.

Adding stringers will definitely help stiffen the hull, but without more information, it is hard to say what you should or shouldn't be doing. Photos of the problem areas would also be helpful. All four of the books you've mentioned are good ones.

I would also recommend you read this post, to help you get more out of your time on sailnet.

[halekai36]

Blue Sky,

It really helps to have an updated profile. There is a ton of knowledge on this forum and if we know your boat we can give a higher level of advice.

See THIS thread for info on updating your profile or adding a signature..

[sailingdog]

Halekai

LOL... I guess we're both pushing our own threads...

[halekai36]

Originally Posted by sailingdog

Halekai

LOL... I guess we're both pushing our own threads...

Dawg,

I forgot you added my post on updating profiles to your's... Overkill alert!!!

[Blueskyzephyr]

Hell Again,

I will look at the threads about updating/improving my profile. As for the source of water I suspect a few sources, winter cabin flooding, bilge spill over at extreme angles of heel, and I will look into the unconfirmed and popular potential points of water entry. I assume my boat to be 40 years old, and that is where it gets interesting.

I puchased this boat in March 2006 from an individual who kept the boat in Portland Conneticut of the Conneticut River. I believe the guy just did some simple work, barrier coted the bottom, painted interior, put new treads on the compainionway ladder, new wire rigging and turnbuckles, and I would say that is the size of it.

It is registered as a Greenwich 24, but I do not believe it is. The cabin has three windows, the Greewich has 2 per side. I have also seen a local greenwich 24, it has less hull volume. I will work on getting some photos up.

Thanks for the thoughts, -Mike

[sailingdog]

If you post your HIN, I'm sure someone can figure out what the boat actually is from the HIN.

[CalebD]

Would there even be a HIN on a boat 40 years old? Of course there would likely be a manufacturers 'sequence' number though which would still be helpful. My 1967 Tartan 27 has no HIN but is identifiable as hull #328 which was made in 1967.

[sailingdog]

HINs were required in 1972 IIRC... if the boat is older than that it may not have a HIN, but it may have a builder's plate located in the cabin someplace.