Best Plywood for a Stitch and Glue

[WishinIwasFishin]

I am thinking about building my first stitch and glue Kayak in the next few months. It will really help me out a lot if some of you could give me some pointers as to the best plywood to use. I have noticed several different kinds mentioned on here but not sure if some of the more expensive brands will be worth the extra money or not.
Thanks

[DarrellS]

The best plywood for boat building is Okuome, but at $70-85 per sheet plus shipping I just can't justify the expense on my personal boats. If I were building them to sell I would use it, but for personal use I am building with 5.2 mm Luan from Lowes or Home Depot.

[TexasZeke]

X2n the luan

kevin

[gerald]

The best plywood to use is a marine grade plywood--usually okoume. There are alternative though. Luan will work. I've built plenty of boats with luan. I will continue to search for alternative plywoods--but I have been burned badly in recent years by assuming that one particular type would work--and it didn't. You must do the boil test. Take several small pieces of the plywood and boil them, let cool, boil again, let cool, boil again, let cool in the water overnight. If it survives without delamination it is probably ok. Usually the wood will fail before the glue joint does.

[bowgarguide]

I use 4 mm 3/16 laun . I have had good luck with it.
Ron

[Dogpaddlin]

I used 1/4 inch birch plywood from Home Depot for my pirogue and would not recommend it. After only a few months the ply is starting to come apart. It makes me want to cry.

[Lollipop]

but for personal use I am building with 5.2 mm Luan from Lowes or Home Depot.

I asked Home Depot and Lowes in San Antonio for exterior Lauan and neither had it and neither thought they could get it. Even Allen and Allen did not carry Exterior Lauan. Am I missing something?

Lollipop

[DarrellS]

It's called underlayment and is in the plywood section.

[Iamdamoder]

They have a don't ask don't tell policy at the big box stores. Don't ask us what we have and we won't have to tell ya that we don't know. Sidestep the clerk and grab it off the shelf from Lowe's. Don't know what the are stocking but Roddis is your go to specialty plywood stop in SA.
http://www.roddislumber.com/" onclick="window.open(this.href);return false;
These guys will be able to answer questions cuz they know their biz.

[WishinIwasFishin]

Thanks guys this helps out a lot.

[Iamdamoder]

I was in Lowe's today. The shelf tag now reads Utility sheeting or sheathing, 5mm, not for underlayment . It looks the same as when it read "exterior luann".

who knows?

[DarrellS]

Home Depot in Waco still says underlayment.

[TexaRican]

How does the luan compare in weight to okume? I know it is cheaper but on my next S&G boat I'll dang sure spring a few extra $ just to get a little bit lighter so I'm planning on okume. After all that hard work it really stinks to have a boat I'm not totally happy with due to the weight. However, I know a big portion of that extra weight was due to first-time-builder overuse of epoxy coats.
I've read the luan can weigh 20lbs/sheet versus 12 on okoume. I used 6mm meranti which is 24lbs and saved maybe $80. Just think, I could have a boat that weighed 16-20lbs less

[bowgarguide]

6 mm
That is heavy
in the 4 mm ( 3/16)there is between 4 and 6 lbs a sheet difference,you actually use about 2 sheets of ply to a boat not counting the scrap,so 8 to 10 lbs is about the difference you are looking at.
All the boats I have built so far have come in from 40 to 46 lbs.
Hope that helps
Ron

[Hirsch]

I used 1/4 inch birch plywood from Home Depot for my pirogue and would not recommend it. After only a few months the ply is starting to come apart. It makes me want to cry.

Thanks for that input! I really liked the looks of your pirogue and might have been tempted.

[preacher]

Just as a heads up . . .

I'm trying to work a deal with McCoys right now. They are looking for a supplier for Okoume and trying to get us the product at somewhat of a reasonable price. I will keep Gerald and all of you up on the info if it pans out.

I'm really hoping for something under $60.00 sheet and may have to buy a whole pallet to get it. If that happens some of you guys will have to take some of that stuff off my hands.

BTW, McCoys delivers FREE.

[gerald]

If McCoys will sell it for under $60 I'll buy it from them. I generally use 4mm, but I'm also looking for 3mm, 6mm, and 12mm...or at least some place where I can order it without hocking the shop....

If I can ever get a deal done like I'm trying I'll just buy 100 sheets, use it, and sell it to the local (central Texas) boat builders. Certainly for under $60. I have little overhead and don't expect to make enough money to retire after selling only 10 sheets....

But...if McCoys can take the pressure off I'll buy from them. I already buy a lot from them and they have me on file for resales.

Oh wait! I read too fast. You ARE talking about maybe having to get a whole pallet. There should be a drastic price difference when buying a full pallet. That's the problem for all lumber yards. They have to buy in large amounts and try to recoup their costs quickly. There really isn't much of a market for marine plywood. It doesn't move fast. I'm a fairly prolific builder and don't use more than 10 or 15 sheets a year. I AM open to buying a pallet load if we can get enough people where we only spend about $500 apiece for 10 sheets or more--preferably more. I would expect closer to $40 a sheet for a pallet load. Plywood and Door in Dallas use to sell 100 sheets at a time for a pretty good price ($27 plus shipping). Don't know what it is now. I've been told by someone that they quoted a much higher price now.

[rodloos]

When you buy a bunch of plywood at a time like that, what do you need to do to preserve it while storing it? I don't think I have a 4' x 8' space free on my garage floor, but will it ruin it to store it standing on edge?

I guess Preacher probably has the space to lay it flat in his nice big shop

[gerald]

All that I get is stored on edge, but that's usually not more than 10 sheets and gets used up in a year or so.

[preacher]

McCoys couldn't pull it off, $74.00 per sheet (with tax) but I have to buy the whole pallet and drive to Houston and back.

Matt at JEM gave me some places to shop and I can get 5 sheets of 1/4 inch okoume BS 1088 delivered to my door for $75.00 per sheet total price. DUH! That price includes a $21.00 delivery for each sheet. Haven't found out about a price break quantity yet, but I'm probably going this direction . . . tired of waiting . . . got to get the SOT under construction.

[JEM]

Proceed with caution if buying from the big box stores. I'm prototyping a new design using the cheap stuff. Here's an excerpt from my build log:

While reading this post, please keep in mind my comments are based on the assumption the hull will have a natural wood finish. If you decide to paint it, some of the comments below may not be applicable.

Here's two images showing a side-by-side comparison. 4mm Okoume is on the left. 5.2mm Exterior grade on the right.





Now you might be thinking: "hey wait a minute...the exterior grade looks like some nice even layers. And you'd be right. However, they also laminate a .5mm skin layer to each side.



And that's where the problems begins. It's hard to find a full sheet with no cracks in it as shown. Also, if you sand on it, be very gentle otherwise it easily disappears and you can see the underlying layers.

I wish I had a large drum sander so I could sand off the paper-thin exterior face plies to see how the wood quality is underneath. But maybe it's best not to look behind the curtain.

The Exterior Grade ply has 2 different colors on each side. Which is another challenge to overcome.



One side has a nice mahogany color... resembling Okoume. The other is almost white in color with some interesting grain lines running in it. The dark horizontal lines are not cracks.

If the color was consistent on both sides of the sheet like Okoume, then it wouldn't matter which side you started working with because they are the same.

[Frank C]

Check the Chesepeake Light Craft site prices for Okoume. I found they were reasonalbly priced for buying a few sheets at a time. I purchased 4 and 6 mm. The plywood was a French import and was of exellent quality.