Plywood hull with no epoxy

[chargerboy]

I did my best to search the forums, I really did. I am willing to bet this question has been asked a hundred times before but I can't find the answer. How do you seal a plywood hull if you aren't laminating it with glass and epoxy?

I am replacing the plywood hull on my cabin cruiser, but have no idea how the original way of doing it back in 1967 was. Nowadays everything looks simple: screw it together and slather epoxy and fiberglass over everything. How can you successfully replace a plywood hull without all the epoxy and fiberglass? Do you caulk the seams of the plywood? Rabbit the edges so they overlap? Or is there some other way?

 

[bigredinohio]

Re: Plywood hull with no epoxy

I'm not trying to be cute but why wouldn't you use epoxy and fiberglass?

 

[Bob_VT]

Re: Plywood hull with no epoxy

Well..... even the plywood hulls I have seen from the early 60's had fiberglass used......

Older wood hulls used brass screws, rope caulk, very tight joints, spar marine varnish and marine paints......shiplap joints

Google search for Glen-L and wooden boat construction. Are you trying to save money?

 

[chargerboy]

Re: Plywood hull with no epoxy

At first I planned to use epoxy and cloth. The boat is a '67 Chris Craft Futura, I don't believe it had any fiberglass on it from the factory, originally I wanted to upgrade when I replaced the hull thinking the fiberglass would be better. After talking to a few more people and doing some online research I've learned that I might create more problems than it's worth with the hull flexing and whatnot. The cost plays a huge role also, and it would be nice to keep the boat in it's original state.

 

[Shife]

Re: Plywood hull with no epoxy

If you are just looking to seal it use 4oz cloth and epoxy. Properly done it will create a perfectly transparent waterproof barrier and you will be the only person that even knows it's there. Top coat with varnish if you're going for the cold molded wood look or paint whatever color floats your boat. then proceed to enjoy a few more decades out of her. You're going to have to seal the plywood with something, might as well throw a thin layer of cloth on there and do it right.

http://209.20.76.247/ss/assets/howto-pub2/Wooden Boat Restoration and Repair.pdf

 

[chargerboy]

Re: Plywood hull with no epoxy

If you are just looking to seal it use 4oz cloth and epoxy. Properly done it will create a perfectly transparent waterproof barrier and you will be the only person that even knows it's there. Top coat with varnish if you're going for the cold molded wood look or paint whatever color floats your boat. then proceed to enjoy a few more decades out of her. You're going to have to seal the plywood with something, might as well throw a thin layer of cloth on there and do it right.

http://209.20.76.247/ss/assets/howto-pub2/Wooden Boat Restoration and Repair.pdf

Will this not just crack and fall off? I mean if I push hard enough on the bow I can feel the wood flex.

 

[chargerboy]

Re: Plywood hull with no epoxy

And thanks for that site, I appreciate the resource, I'll make sure to keep this handy

 

[Shife]

Re: Plywood hull with no epoxy

Will this not just crack and fall off? I mean if I push hard enough on the bow I can feel the wood flex.

Not if properly applied. 4oz cloth is very thin and flexible when cured. It is used to provide abrasion resistance and protect the wood. There are great many beautiful restored wood runabouts that look like they have 30 coats of varnish on them. Chances are what you are actually seeing is an epoxy coating reinforced with 4oz cloth and covered with a few coats of varnish for UV resistance. Quality 4 and 6oz cloth is invisible when wet out with epoxy.

 

[Shife]

Re: Plywood hull with no epoxy

After doing some research on your boat I'm thinking you might want to consult the folks at Chris Craft or West Systems before you pull the trigger on this project. This type of hull construction may very well need glass sheathing far more substantial than 4oz cloth to be successful, and sheathing with glass may not be worthwhile for this boat.

This forum is likely not going to be the best place for advice on this. You might want to fire off some emails to the experts. Without knowing the specific method of construction any advice is suspect.

http://www.epoxyworks.com/23/pdf/09-Bounty_Hunter.pdf