Question about redesigning substructure 1965 boat.

[rickou812]

In the process of restoration, had to cut the original fiberglass floor out to get to the rotted substructure.

I cleaned all the crap out and got down to the layout of the original wood.

The wood was 1x3's layed flat. The first one was started dead center running length wise from the transom to about 3-4 foot from the nose. The rest was layed side to side. Then a final board was layed on edge down the center. They was only glassed in around the perimeter.

Then a layer glass was layed to make the actual floor.

What I do not understand is the logic behind this design. The wood was not protected in any way from water. It actually was forced to lay in water because the drain whole was above the wood, above the floor.

Now the question is, how could this modified or redesigned in a way that would promote better drainage and protect the wood?

Here is a picture to try to point out what I am saying above:

Here is a shot that gives a view of how the original boards where glassed in:

Thanks

 

[jonesg]

Re: Question about redesigning substructure 1965 boat.

best bet is not to put wood back in there, there is no drain.!
I would investigate various foams that can be used with polyester,
urethane foams are good,
just cut to the same dimensions as the original stringers.

it looks like the deck was premolded and placed on top of the stringers, thats why the stringers were flat planks.

Or if you just want to go cheap, go back with planks again and glass them completely to seal, they'll last a few yrs.

 

[rickou812]

Re: Question about redesigning substructure 1965 boat.

best bet is not to put wood back in there, there is no drain.!
I would investigate various foams that can be used with polyester,
urethane foams are good,
just cut to the same dimensions as the original stringers.

it looks like the deck was premolded and placed on top of the stringers, thats why the stringers were flat planks.

Or if you just want to go cheap, go back with planks again and glass them completely to seal, they'll last a few yrs.

I had thought about structural foam. But I was also thinking about composite boards. The type that are used for decking that are made from recycled materials. They are a little pricey, but the would never rot. The only I was not sure about is if the glass would stick...?
Here is what I am referring to:

 

[Bob_VT]

Re: Question about redesigning substructure 1965 boat.

Trex/synthetic plastic/recycled plastic manufactured boards really are not good for marine work.

 

[MushCreek]

Re: Question about redesigning substructure 1965 boat.

The real role of the core material is to give shape to the fiberglass, which actually becomes the beam. I've used all sorts of materials for coring- we reinforced car fenders with garden hose! Those composite boards are heavy and the 'glass may not stick. Foam is your best choice, heavily layed up with fab-mat and or roving to build some thickness and strength.

 

[ondarvr]

Re: Question about redesigning substructure 1965 boat.

That type of composite deck board is, well, junk. They're heavy, costly and weak, all you really get is a shape to glass around, you'd be better off with wood.

If you rebuild it the same way it was built originally, only use some care and do a better job than they did, it will last a very long time. Foam will work also, but you need to use more glass to make up for the strength the wood supplied, so if you add the extra glass and use wood, then it won't make a difference if at some time in the future the wood does start to rot.

 

[rickou812]

Re: Question about redesigning substructure 1965 boat.

Thanks for the advice. I will stick with wood. Should I used pressure treated 1x4's, or something else?

Thanks,
Rick

 

[rickou812]

Re: Question about redesigning substructure 1965 boat.

Thanks for the advice. I will stick with wood. Should I used pressure treated 1x4's, or something else?

Thanks,
Rick

A bump for the question,

Thanks

 

[jonesg]

Re: Question about redesigning substructure 1965 boat.

it might be cheaper and stronger to buy a 4x8 sheet of exterior grade PT plywood and rip your stringers from that, dry it first ...or last,
but make sure its dry or the resin will not take or cure.

I built a small elec box last yr and resined the bottom whilst it was damp from sitting somewhere wet ( I guess).
Haha now the resin will not cure.
I slapped another coat over it with a hot shot of catalyst and it still won't fully cure, so I put a heat gun on it and boiled the resin and it still won't cure.

You get the picture. Ita gotta be dry.

Try stacking the stringers together and slap a ton of resin on the edges and ends, let it soak in and keep drowning with more resin, just before it goes off seperate them and do the other side after it cures .

 

[rickou812]

Re: Question about redesigning substructure 1965 boat.

it might be cheaper and stronger to buy a 4x8 sheet of exterior grade PT plywood and rip your stringers from that, dry it first ...or last,
but make sure its dry or the resin will not take or cure.

I built a small elec box last yr and resined the bottom whilst it was damp from sitting somewhere wet ( I guess).
Haha now the resin will not cure.
I slapped another coat over it with a hot shot of catalyst and it still won't fully cure, so I put a heat gun on it and boiled the resin and it still won't cure.

You get the picture. Ita gotta be dry.

Try stacking the stringers together and slap a ton of resin on the edges and ends, let it soak in and keep drowning with more resin, just before it goes off seperate them and do the other side after it cures .

That sounds like a good idea. I have to buy the ply anyhow for the transom...