Gelcoat

First point,
saturated is not gone! As long as there is no rot, you can drill holes and get it dry again. The question is, if it still has a good bond to the inner layers. (probably even to the outer) If not, the boat is gone!
Just the inner layer alone will not hold the shape of the boat with all the interior attached to it, and one can not support it when working on the outside.

Thats worth to check first!

The system you have in mind will not work here. Cold moulding means several layers of veneer over a wooden structure. Though a veneer would stick to the inner layer of your hull structure when you use epoxy, there is nothing left in the hull holding the shape once the outer skin and the core is removed.
Then there is nothing to attach the veneer to! Not enough bulkheads, no frames where you could screw or nail the veneer on until the resin is fully cured.

Another way to skin the cat might be to build a similar boat in cold moulded or strip planked method and use the old sampan as a organ donor only. Not cheap, not easy though, even if there are plans available.

Regards
Richard

 

Jim I wouldn't be sanding thru the gel coat, I would be cutting thru the gel coat and the balsa core and removing them. Yes of course the surveyor mapped out the wet areas.
tunnels,
Yes I am one of those people that like messing about in boats. I can't find a boat that meets my needs like this boat does. Now it has become far less expensive due to the survey.
My question now is how well do polyester resin and epoxy coexist?

 

apex
I can figure out a way to support the boat, I think I can vacumn bag the veneer to the inner hull. Which leaves me with the question, do poloyesther resins coexist with epoxy?

 

I think the point Apex was making about support is that in cold-molded construction there are closely spaced support members for the cold-molding process, usually longitudinals. Here are a couple of examples:





It is not clear to me that if all that is left is the inner skin of a cored hull that there will be enough support to cold-mold on top of it. Although I have never done it (or heard of it being done) so I could be wrong.

Ralph

 

Do polyester and epoxy co exist NO

Lets go back to the begining !
How did the water get into the core ?
How big are the wet patchs ?
How thick is the Balsa core ?
Has the boat been in fresh or salt water ??
For me being a glassing person trying to make a wood hull round what you have would be a disaster, sure it could be strip planked using Cedar as the inner core and sticking everything with epoxy resin .
Remember the gel coat you always refer to is just a coat of colored resin with glass over it .
If you understand vac bagging then you are a good way to simply re-coreing to the inner skin of whats there ,but you could use Vinylester resin to adhere to the inner skin , then carry on with Vinylester for the rest of the outside glassing and fairing , filling etc to the final paint stage .

If you have to do a total recore i would be doing it using with sheet foam core . I will leave you with these thoughts at this point and wait for the responces that will follow !!

 

To answer the last question first, Epoxy on poly does a perfect job, poly on poly does not stick well. Not VE either!

To the more important "building up a new hull" question.

As far as I understood this is a round bilge sailing boat right?

If so, then there is no way a veneer layer could be properly attached to the paper thin inner GRP layup.

Sorry.

BTW a few pictures would probably clear the view!?

And have you ever seen the "Pascoe" papers on such issue? That is sure not the bible but a quite eye opening lecture.......
http://www.yachtsurvey.com/structuralissues.htm

You are right on the spot Ralph. And I like to add, that the same support is required in this case when you strip plank. (where I would have no idea how to pass the loads from the stem into the structure, due to the lack of a wooden stem / keel arrangement)

Regards
Richard

 

Just to clear the air on the 3 resin systems
Polyester resing is the cheapest and easyest resin to use for production boat building of any size or shape .

Vinylester is the next step up the quality level . Has much better properties like stickablity and chemical resistance hence better in the fight with osmosis . Sticks well to polyester and in manufacture is used as a foundation barrier layer for the first lot of glass laid against the gelcoat as a barrier agains osmosis.

Epoxy is a good alrounder but like all things good it comes at a cost .

Remember each of these systems has a great long list of formulations for differant applications and uses !!

Epoxy will stick to vinylester and polyester !!!!

Polyester does not adhere epoxy
Polyester only adheres to vinylester in a wet on wet situation and does not adhere very well to vinylester once it has hardened 100% .

Vinylester will adhere to polyester wet on wet and once polyester has hardened 100% .

Polyester and vinylester do not adhere to Epoxy !!

 

Thanks for that........
Now, finally I know why I mainly built Boats using Epoxy in the past 35 years.

Not as good as Epoxy!:!:

Right Epoxy holds on both of them, but both do´nt hold on EP (and hardly on anything else)

And btw. the price difference between VE and EP is close to zero for a homebuilder! Therefore not worth to waste just one thought on VE or poly.

Regards
Richard

 

Like all materials we use some are good some not so good some can be compatable with others some are not . Simply wood and fibreglass are not compatable . No i hear some disputes before i have even finished .
Polyester does not stick to wood very well at all . neither does Vinylester . Proper formulated epoxies Yes .
So if you build anything at all with wood inside of a polyester glass object and there is moisture some where near or the wood is damp or wet then eventually you will have problems .Simply dont do it .
Over more than 30 years in the glassing industry , marine and industrial companies i have worked we have used Balsa cores and never ever had a problem with dampness of rot or water getting into a core in anyway shape or form . Some hulls in powerboats we have used combinations of Balsa in the bottoms and Foam in the topsides , again never ever a problem . most recent foam totall from gunwhale to gunwhale , never had a problem ever .
The question i always ask is how did the water /moisture get into the core ?? If a hull has been damaged then i can understand but with balsa moisture can not travel sideways because of the structure of the balsa blocks used .
80% of probelms and failures with fibreglass objects is Bad workmanship . simply the guys done care of they dont know so who do you point the finger at ?? The bosses !!
One they should be on the job watching and making sure of what going on . and two they should have schooled the guys on how to do the job properly in the first place . Every hour of every day there is constant changes taking place temprature and humidity is constantly changing and everyone has to be completely aware of there surroundings and those changes that are taking place .
20% of failures can be cotributed to poor selection and choice of materials being used to make what ever it is .
Two people can make the same object yet they can be completely differant , one will last for a long time , the other breaks and falls apart bu they could have used exactly the same materials .
Understanding the materials you are working with and how to get the best advantage from them is very important and only comes from exsperiance and disecting other peoples failures to find out why it failed .
I am not pointing the finger but some of the worst made and put together boats i have ever seen have been mass produced boats with names we all know and have seen for years .
My favorite is THE PROBLEMS WE COVER UP TODAY ARE THE DISASTERS AND LAWSUITES OF TOMORROW

 

Thanks guys
From what you all have said, is there really anyway to dry a wet balsa core?
I'm sure it's possible to stop the water intrusion but will that just ensure the core will never dry?

 

I'll try and post a picture from the survey

 

Time to uncover the unknown !!

Like i asked before the water where ever it got in should not have travelled side ways , maybe just a little but not to far . if you cut the glass off the surface and strip and rip it off then you will see what you have and how far it could have travelled if at all , and how much moisture /water is there . If its got salt in it then it will have to come off, an air operated sharp, wide, chisel and then a grind to get back to the bare glass inner skin.

Glass is easy to repair and modify just need to think a little about how you are going to do the job .

 

chandler,

...as you have not purchased this boat yet, why would you even contemplate going on with the purchase.....it is far better to simply go buy a good boat, and there are many bargains out there today just waiting for buyers....frigging about with trying to solve someone elses problems sounds to me like a bad idea.

 

One more important point - if I understand you correctly you are considering removing the external laminate and core. Typically, the stronger laminates are external and the thinner weaker laminates internal. Therefore, if you remove external and core you are not going to have anything holding the hull's true shape. It'll distort terribly and all you'll have is a huge mess. DON'T DO IT!

 

Not to pester you, but how much are they asking for this? Boats at docks run up huge bills and get abandoned. They can often be had for a portion of the dock fees.

Is this a year 1982 Freedom CK or an 82 foot Freedom CK?