Re: 1971 Flatback in Boca

[John Jones]

Everyone has an opinion.  You have to do what makes the most sense to you.

[gran398]

Well, I was wrong. The boys are right. Just got off the phone with a professional builder. He says to make sure the wood is completely dry, and glass BOTH sides and all edges...completely encapsulated.

Sorry for the bad info. Best luck in your rebuild! gran

[wingtime]

Another thing to keep in mind is not all marine plywood is created equal...  Not only should the glue be water proof but hat type of wood is used to make it?  I used a high quality okoume marine plywood when I rebuilt my coffin cover.  Here is a good read on marine plywood.  http://www.glen-l.com/weblettr/weblette ... ywood.html

[GoneFission]

Glass on both sides is the way to go.  It not only seals the wood, but adds substantially to overall strength.  

See ya on the water!

[slvrlng]

Rot is the reason i am not going to use plywood. I found a product called nyloboard that is made near my house in Covington Ga. It is made from recycled carpet fiber and will not rot. Check it out!

www.nyloboard.com

[seabob4]

Regardless of the choice of material, the best case scenario is to not allow any moisture intrusion, read that water.  Seal edges, seal holes (not just a squirt in the hole before you insert the screw, enough so that when you tighten down the screw, you have squeeze out from under the screw head), seal ANYTHING that can potentially allow water intrusion...period.

It doesn't mean you have to fanatical about proper installation, it just means you have to do it right...

[dbiscayne]

There's some misinterpretation being thrown around about not sealing the wood completely regarding one of my past posts- what I was told by several wood boat builders - that leave their boats in the water most of the year - was to coat the wood completely with thinned resin, then coat the sides & bottom of the decking with regular non-thinned resin, lay the deck out & screw down then glass over the top.  I used this method on my 23' boat in 1995 & it's still solid.  The boat stays outside year round, but I do keep the hatches open to let it breathe.  I'd never leave just raw wood on the boat anywhere.   Heres a pic of the wood from around 2004 when I cut out a hatch opening, 5/8" BC plywood, not even marine ply.


The previous owner had completely encapsulated the wood deck with glass, then screwed it down.  The screws were not sealed well, water definitely got to the wood, his deck lasted about 5 years or less I'm guessing when I got hold of the boat, by then the deck was mush.  The extra layer of 24oz roven he used on the bottom side didn't help much strength wise, sealing up all the screw holes is key.
I do think that if water had never gotten to the wood it would've been fine wether it's glassed on both sides or just the top.

The wood by itself is plenty strong, the glass is only there to protect it, you really don't need to glass both sides for strength.  Foam core then yes both sides but thats a completely different scenario.  3/4" marine ply is overkill for the deck, 5/8" is enough unless you've got some huge unsupported areas in which case you should build some kind of reinforcement grids to the deck.  The factory 19' boats came with 3/8" ply.

[Capt Matt]

Don't use screws and stick the deck down with 5200 or epoxy.
I'm going to stick my 3/4 coosa floor with 5200 and weight it on the stringers and bulk heads till it cures
Matt

[bumpster]

Don't use screws and stick the deck down with 5200 or epoxy.
I'm going to stick my 3/4 coosa floor with 5200 and weight it on the stringers and bulk heads till it cures
Matt

I am no expert but i dont think 5200 is the way to go. Most builders use polyester resin mixed with a thickener to attach the decks to the stringers. 5200 is not a rigid adhesive compared to the polyester paste. Of course I am not a builder so this is just a semi educated opinion from a guy that has rebuilt only one boat in his life

[wrightex]

Thanks guys for all the advice. Glad I asked the question!

The bottom of the floor now has a fresh layer of 1708. Hope to get the floor in this weekend, weather permitting. It will be fully encapsulated. Planning on using 5200 to bond to stringers. I'll probably use some screws to secure it until it bonds, then remove screws.

gran398 - you could sell ice to an eskimo. Had me convinced of the "old boat builder" way. I'll be watching you from now on.   :)

I know, pics, pics, pics - sheesh....

[wrightex]

I guess the new question is what to use to bond the floor to the stringers/bulkheads?

My adviser (Beeerman) recommends epoxy, but I've got 5200 available.  

[pete]

I have seen many builders weighting down the deck with whatever is handy to hold it down while the "deck bonding agent "cures,rather than put screws in their new deck

[dirtwheelsfl]

thickened epoxy to bed it and countersunk screws every foot or so. you want to get squeeze out of the epoxy everywhere. screws will do a better, more even job than weights. i use square head stainless deck screws. leave em in, fill the heads and glass over them

[LilRichard]

A lot of folks use 5200, it is more flexible and is a permanent bond as well.  I'm not knocking the epoxy route, it will work fine too.

[gran398]

Thanks guys for all the advice. Glad I asked the question!

The bottom of the floor now has a fresh layer of 1708. Hope to get the floor in this weekend, weather permitting. It will be fully encapsulated. Planning on using 5200 to bond to stringers. I'll probably use some screws to secure it until it bonds, then remove screws.

gran398 - you could sell ice to an eskimo. Had me convinced of the "old boat builder" way. I'll be watching you from now on.   :)

I know, pics, pics, pics - sheesh....

Hey thanks.....I love eskimos....and penguins.

 

You know, as JJ said, there are two sides to every coin. I remember my old wooden boats  30 years back, drying them out, and dumping copper napthanate in the bilge over the winter. The old boatbuilder way. Some guys glassed their bilges...quick death.

Nothing wrong with the old boatbuider way. And as mentioned, if fully sealed, but an improper install....she rots out double-quick.

Anyhow, you may still need to keep an eye out...