Pourable transom compound as a deck core?

[wingnut]

Hey guys, I am considering a new project - not an Aquasport, but incorporates some questions and lessons learned from my 170 rebuild last year.

I have the possibility to acquire a Sabre 34 sailboat, for free. Owned and sailed for years by a friend, the deck core began to get soft. He began the rebuild, and skinned off the top layer of fiberglass in the soft areas, then removed the wood core below, then lost interest. The area that was removed is pretty significant, maybe 20% total of side deck, cabin top, and foredeck area. Call it 40 square feet total. Not large enough areas that I am concerned about sagging or integrity of the deck as a whole. The boat is very sound otherwise. The deck just needs to be recored in the removed areas, then fared and new non-skid applied. I don't have any photos at this point, but can get some soon hopefully.

My question for all of you: rather than putting some kind of core material like Coosa down, and having to fit/shape/fasten/grind/glass/fare each piece, could I use thickened pourable transom compound, trowel it into the core voids, and glass over? Seems to me that this would be a great solution to adhere to the void and engage the full composite deck strength. I'm envisioning thickening with West System colloidal silica or similar, then sanding and glassing over. I am not overly concerned about a slight weight increase. 10 gallons of material would easily fill all of the missing core, so call it 70 lbs or so, vs 40-50 using wood.

Any thoughts on this? Any downsides that I'm not seeing? Anybody ever used the stuff as a deck core material?

Thanks in advance for the thoughts!

[dbiscayne]

Whats left of the old inner layer of fiberglass that was left behind after the core was removed? With a plywood core the glass thickness isn't as structural, but if you replace with a composite core the glass does become a major part of the structural component.  Seems like it might turn into a lot more work with the pourable material. Fairing that stuff might be a nightmare it probably doesn't sand too well, just a guess though. Controlling the thickness, getting it consistent would be a lot of work. My preference would be to find a foam core that's scored so it bends well and with a thickness of the existing core. Add some glass to the existing skin if needed, cut the new core into small pieces if needed to work it better, trowel thickened epoxy onto the skin and stick it down. You could use weights or temporary screws to hold it down. Then glass over.

[wingnut]

Thanks for the input. You are probably right, I should not try to reinvent the wheel! Just trying to think through alternate solutions as I figure out if I want to jump into the project.

It is a cool boat but a lot of work to get it back to top condition. Also need to figure out where to put a 34' sailboat...