OT CCA marine plywood
- Thread starter scbadiver
- Start date
Ok...first things first...marine plywood is not treated against water in any way. What you want is CCA treated Plywood. Go to Home Depot on Cave Springs and thell them you want them to order it from Forest Products, they will know what to do. We distribute the real CCA plywood but that should not be confused with Marine Grade Plywood...totally different creatures.
scbadiver
New member
Hey Jack, Thanks for the info. My confusion stems from the web sites I,ve been to from the boat supply places all list "4x8 7 ply marine plywwod CCA treated. Top side sanded smooth and all voids filled" My understanding was that real marine ply has no voids and is waterproof glue. I can get CCA ply for about $40 a sheet in yellow pine OR marine ply in fir for about $100. This is to be used on a pontoon boat deck. The suppliers I spoke to gave a lifetime warr on thier "Marine CCA" Is my leg being tugged upon somewhere?? Thanks for any help and guidance. BTW - the boat suplliers get about $70 per sheet plus shipping.
It is possible to get marine cca plywood, but it is not a normal stock item in this area. Marine Grade is AB Fir plywood, and what makes it different from reg. AB or AC or any other plywood is the inner plies are all B grade and better with absolutely no voids and a resourcinol glue (waterproof). What you end up with is a very structurally strong plywood that was primarily used in boatbuilding. Back in the 50's and 60's a lot of boats were plywood hulls and that is where this product came about. It was also used for transoms because of the strength. Marine Grade will rot as it has no protection from water damage. It must be sealed from water absorption.
For a deck on a pontoon boat, use regular CCA treated Plywood as you will most likely have it covered with carpet anyway. It is strong enough and will not rot. CCA is safe, has always been safe and the form of arsenic in it is a naturally occurring form that is found everywhere. You ingested more of this as a child eating dirt than you ever could from CCA treated wood. I spent 5 years at a treating plant and understand the differences in CCA and ACQ. ACQ will rot in time, is highly corrosive to metal because of the great amount of copper in it. It will eat through aluminum in as little as year with direct contact.
I have been in the wood industry since 1984 and have fought this misconception the entire time. Enjoy the boat.
For a deck on a pontoon boat, use regular CCA treated Plywood as you will most likely have it covered with carpet anyway. It is strong enough and will not rot. CCA is safe, has always been safe and the form of arsenic in it is a naturally occurring form that is found everywhere. You ingested more of this as a child eating dirt than you ever could from CCA treated wood. I spent 5 years at a treating plant and understand the differences in CCA and ACQ. ACQ will rot in time, is highly corrosive to metal because of the great amount of copper in it. It will eat through aluminum in as little as year with direct contact.
I have been in the wood industry since 1984 and have fought this misconception the entire time. Enjoy the boat.
Any lumberyard has access to it, if they squabble or are uneducated tell them where to get it. No one wants to stock it, it is too expensive. One thing about the IPE, it will shrink...a lot!!! Tiger doesn't shrink but it isn't in normal sizes as it is intended for a deck. The cell structure of Ipe prevents it from being properly kiln dried, it becomes what is known as "case hardened" and will only dry so much, but there is still a lot of loisture in it. Tiger doesn't have this problem and is kiln dried to 8% post kiln and will equalize with the environment it is in which means normally around 12% moisture. It is a very stable product, just not as strong as Ipe.
You can do it and yes carbide is needed. One of the problems associated with drying it so much in the kiln is the wood is frequently warped a little, it can be straightened but it does require more skill to work with. I don't think you will have any problems.
