Balsa Core location in Hull

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Southern Gales
Posts: 101
Joined: Mon Mar 24, 2014 2:10 pm
Location: North New Jersey

Balsa Core location in Hull

Post by Southern Gales »

Good morning. I understand from other posts the transom is balsa cored but I was hoping to find out if this is the case on the sides of the hull. I have an 18" void in the hull above the waterline that needs repaired between midship and the transom. I plan to do all the work from the inside the cabin. I would like to know the thicknesses of the hull cross-section (internal glass and core thickness) in this area.
Thanks.
~Chris
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Southern Gales
Posts: 101
Joined: Mon Mar 24, 2014 2:10 pm
Location: North New Jersey

Re: Balsa Core location in Hull

Post by Southern Gales »

Balsa core thickness in this area is 1/2"
~Chris
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wkwtucson
Posts: 41
Joined: Fri Nov 02, 2007 12:20 pm

Re: Balsa Core location in Hull

Post by wkwtucson »

Recent repairs on the boat and research with other 7.9 owners and repair folks suggests that the whole boat (hull and deck except under mast step) is cored balsa. The major exception to this is that there appears to be a strip of solid glass along the very bottom that is about 9" wide between the outer and inner skins that runs from stem to stern. Let me know, if anyone wants some photos.
Kevin W. #29
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SailingUphill
Posts: 204
Joined: Fri Aug 17, 2012 1:52 pm

Re: Balsa Core location in Hull

Post by SailingUphill »

Its about this thick throughout the hull. This is the starboard bow quarter
Image

This is the hull, directly in front of the keel
Image

So 1/2" balsa end grain throughout the hull in only very non-structural parts does it not have core, a few places (like the mast step) where its marine ply and or metal.
Presently hull 399, "Ragtime" Blackwater Yacht Racing, Smith Mountain Lake, VA
Fomerly hull 68,"Rum Line," Paupack Sail Club, Lake Wallenpaupack, PA.
Stef
Posts: 342
Joined: Thu Jan 15, 2004 9:40 pm
Location: NE Pennsylvania

Re: Balsa Core location in Hull

Post by Stef »

It's a 1/2" thick balsa, everywhere. The only area not balsa in the hull from the factory is in front of the daggerboard trunk. That's a good place to put a shoot through hull transducer.
I had an area in front of the mast step that was soft. Soaked balsa. I did all the work from inside the cabin. One culprit was the small block mounted to the deck for spinnaker down haul, I made that solid glass, so if it leaked again, no worries about the balsa.
I also bent a nail and put it in a drill, then dug out the balsa around the chainplate. Solid glass there now too.
Stef
Odyssey #146
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