what kind of plywood is every one using

boatnut74

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Re: what kind of plywood is every one using

Alot of us are using Auruco ply that you get get from Menards or Home Depot. Pretty good stuff IMO.
 

GT1000000

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Re: what kind of plywood is every one using

I found some incredibly nice Exterior Grade AC Fir at a local lumber yard...good prices , too.
 
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Re: what kind of plywood is every one using

funny you should ask. i was on a boat building forum recently and reviewing recommendations for building wood boats. this included some glass boat info as well, but most important...they talked about wood...plywood in particular. the interesting thing i saw was they said...ready for this? it doesn't matter if you use marine or plain plywood...exterior or interior IF, and there is an IF, you use epoxy, encapsulate, and do it correctly. some here will agree...others will not. they said, epoxy seals the wood...polyester resins are not waterproof...or as waterproof as epoxy. now...there is a but, cuz there is always a but....if i were going to spend a ton o'money on a restoration, i would probably use marine and epoxy in that marine has no voids. if you are replacing the transom is your tinnie or small bass boat, most any plywood will last you (done correctly) for a long time. do your homework, read a lot, and listen. visit a boat yard if there is one near you.
 

Beefer

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Re: what kind of plywood is every one using

I just repaired a large floor panel in my cockpit, and was going to use plywood, but decided to use Prisma Preforms. Ended up being cheaper, lighter, and easier to work with then wood. They also make stringers. This stuff will never rot. Here's a link to my step-by-step repair using the product. You'd be surprised at the cost! http://forums.iboats.com/showthread.php?t=530131
 

lmuss53

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Re: what kind of plywood is every one using

Arauco ACX from Lowes, sealed in epoxy for the transom and Rusto Polyurethane for the decks.
 

Woodonglass

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Re: what kind of plywood is every one using

The Arauco Ply is 7ply, and so far I have found no voids to speak of in the sheets I have purchased. 100% waterproof glue. I see no reason not to use it. The IF mentioned above is very true. No wood not even Marine Grade will last IF it is not properly coated and installed and maintained.
 

ImWingnut

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Re: what kind of plywood is every one using

MDO, 1 side finished. $44 for a sheet here and the resin based adhesive in the layers gives me more peace of mind if water ever does get to it (or rather when it does get to it). Can't get it at the local Lowes or HD, had to go to a lumber supply house. Good stuff, used in outdoor signs other outdoor applications where exposed to the elements.
 

MichaelP

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Re: what kind of plywood is every one using

The Arauco Ply is 7ply, and so far I have found no voids to speak of in the sheets I have purchased. 100% waterproof glue. I see no reason not to use it. The IF mentioned above is very true. No wood not even Marine Grade will last IF it is not properly coated and installed and maintained.


^^X2
Is MDO aka Advantec?
 

jasoutside

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Re: what kind of plywood is every one using

I'll need to jump in with another vote for Arauco here. I've used both Marine Grade and Arauco and the difference was hardly noticeable, well, except the fact Arauco was about 1/2 the price:D

P1060956.jpg
 

Woodonglass

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Re: what kind of plywood is every one using

I really like MDO and HDO plywood too! Some really good stuff but... Hard to find and a bit more pricey than the Arauco. Since the Arauco is so easy to obtain I have switched to it. One good thing about the MDO is it saves quite a bit in resin since it does NOT drink resin like the Arauco does. For Decks the MDO is a Great Option.
 

oops!

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Re: what kind of plywood is every one using

Not to hijack....

But you want the wood to drink the resin on the inital wet out.
The more the wood drinks the resin...the better bond you will have to the glass.....If the saturation is minimal.....this means a resin rich layer is building on the substraight. (the new ply) and as we know.....a resin rich layer is a weak bond.

This is also why we dry the wood for as long as we can....we want to make sure the resin penetrates the wood.
A properly dryed piece of ply...with a well glassed first layer....is really tough to de-bond. The plywood will actually pull apart before the resin between the glass and wood fails.

During resin testing from the manufacturers, they coat a piece of ply with resin....let it tack (not cure) then glass a layer of 1.5 csm on the wood. then....after full cure......they use pliers and try to pull the glass form the wood. then they see what has failed.
they look at the csm.....is there wood on the csm?.....if so....that means the wood failed before the resin bond did.....this is a good bond.
However if the reverse happens....where the glass pulls from the wood with out any wood on the glass.....this means the resin failed....then they find out why....and tweak the resin mixture.

For this reason......people have tried to thin resin with acetone so it penetrates the wood easier, however....when doing this...they actually weaken the resin is self.....so they think they are doing it better...but in fact they are working against them selves.

Epoxy.....is a really good glue....and far exceeds the amount of pressure needed to de laminate fiberglass from a plywood substraight.
However......due to the cost of epoxy...it makes production building prohibitive.

Keep in mind, using the lowest grade cheap carp poly resin.....even the weakest bond to plywood, will last many many years.
Poly resin is that good of a building material.
 
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Re: what kind of plywood is every one using

"Epoxy.....is a really good glue....and far exceeds the amount of pressure needed to de laminate fiberglass form a plywood substraight.
However......due to the cost of epoxy...it makes production building prohibitive."

oops, It is agreed resin is more cost effective from a production perspective, but what about the one-shot guy that is rebuilding his project? Wouldn't it make sense to use epoxy rather than poly?
 

jasoutside

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Re: what kind of plywood is every one using

As a matter of practice, metal heads (aluminum boats) like the epoxy, glitter boat guys (fiberglass boats) like the poly.:D

(This is in no way an attempt to start yet another glass vs. alum thread. I'm just sayin.)
 

oops!

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Re: what kind of plywood is every one using

that is a great question bud.....and so we dont hijack this thread....im going to start a new one.
 

oops!

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Re: what kind of plywood is every one using

(This is in no way an attempt to start yet another glass vs. alum thread. I'm just sayin.)

fibber,......lol :D

im going to start another thread.....im really hoping it does not turn into an epoxy vs poly thread....lol
 

catfishr1

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Re: what kind of plywood is every one using

Thank you panama. I was leaning toward marine grade plywood. After reading through this thread, am lea:pning toward arauco.
 

panamacitymustang

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Re: what kind of plywood is every one using

Lol I was leaning the same way but I'll be going with arauco as well. One more question is how to properly seal this wood with epoxy before glassing
 
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