Large plywood sheets?

[Cyberjag]

I'm looking for a couple 1/4" by 4' by 16' pieces of marine plywood and can't find them anywhere. Does anyone know who sells these? I live in the Charlotte NC area, but they just don't sell it around here.

[Rum_Pirate]

You could scarf a couple of sheets together.

Unless of course, the joints would pose a problem for your project.

However, you could try Robichaux's Lumber Company in Raceland, Louisiana 504-447-7035

I understand that they have supplied 1/4 x 4 x 16 marine plywood.

[Paul Girouard]

Never seen sheet good longer than 12 foot. Marine or other wise.

Good luck and you better rob a bank IF you find it:eek:

[Ron Paro]

Typically the marine ply is purchased in 8' lengths, and then joined end-to-end with epoxied scarf joints. I have seen a distributor in Mass. that sold scarfed together sheets, up to 16' in length, but I don't remember the name. Shipping of this would be extremely expensive. Here is the link to my blog page that describes the process... http://jimmyskiff.blogspot.com/2006/12/not-so-scary-scarf-joints.html

http://bp3.blogger.com/_XuaT2XHyCMw/RYPpqVAlcDI/AAAAAAAAAAw/LJWWJ6Xd-Jg/s200/th_IMG_2741.JPG http://bp0.blogger.com/_XuaT2XHyCMw/RYPpqlAlcEI/AAAAAAAAAA4/vtADZMXtCA4/s200/th_IMG_2742.JPG

[David G]

Our family used to be in the plywood business. Things have changed since then, but I'll describe the current situation as best I know it. I'm not aware of any source for any type of plywood with a single, integrated panel bigger than a 5' X 12' layup. In marine plywood, make that 4' X 8'. Some suppliers - check Boulter in Mass. or Edensaw in Washington - will supply factory-scarfed sheets up to 4' X 16'.

This industry, as many others, is fluid. Your best bet is to check with some knowledgable suppliers for the current lowdown. For instance, I've heard that some of the old plywood equipment (including presses big enough to do the 4 X 12 & 5 X 16 layups) have been exported to developing countries. It may be that some of their product is available in this country. Or, you could check the Joubert (mfgr. of marine ply) website. If they make it, they can tell you where to buy it. In truth, I very much doubt that you'll find the product you're looking for. I suspect you're looking at scarfing, or butt-blocks, or Payson butts.

"Some people like my advice so much that they frame it on the wall instead of using it up" -- Gordon R. Dickson

[Cuyahoga Chuck]

At one time Harbor Sales in Maryland had a machine that would scarf joint 8' plywood panels into any length the customer desired. Their longest effort was a 75' strip that went to the Naval Academy for a boatbuilding project. Don't know if they still do it.

[David G]

Oops, I should have mentioned that my post (#5 above) refers only to availability of small quantities of plywood. There are mills that will be happy to lay up a train-car load of larger panels of construction plywood (douglas fir or similar) for you. Some might be willing to mfg. in smaller quantities, but probably not much smaller. You'll just have to discuss it with your local supplier to know exactly. It's a bit spendy, per sheet, but the real bugaboo is the quantity. A backyard boatbuilder is unlikely to be willing to buy such large lots. Even the lumber retailers aren't gonna stock such a quantity of such a slow moving item. I'm less familiar with the marine plywood supply chain, but I'm guessing that - even if the capacity exists for large panel mfg. - the same distribution dynamic applies.

"Chance favours the prepared mind" -- Louis Pasteur

[james burt]

check out clemmons hardwood, in winston-salem
their number is 336.760.4336
good luck

[mcdenny]

Scarfing is pretty easy and cheap. Is there a particular reason you can't have a scarf joint in your project?

[Tom Lathrop]

If you can build a wooden boat, you can scarf two sheets of 4X8 together. It is not difficult, just often intimidating to a novice. Take the plunge. After you have done that, confidence soars so other tasks seem much easier. Instructions are in about every book on plywood boats and all you need is a sharp hand plane and elbow grease. Good luck.

Even if you found a source for 4X16 plywood, the shipping costs would be a fright. In my experience, supplier scarfs are not all that good anyway.

[htom]

Big sheets used to be available at huge premiums, but I haven't seen any for decades. 1967 was the last time I saw one; teak, both sides, 5/8", 4' x 20', N/N finish marine. He had to order two of them (he only needed one), and they came via train in a huge crate that had 4' x 20' sheets of fir or pine sandwiching the teak. The rest of us in the shop figured out that we could have ordered teak, 5/4 random width 20', cut it into 1/4" squares, and glued those onto 1/4" plywood for less -- and had lots of leftovers.

[JimConlin]

Veneers are sometimes available in longer lengths, So, if you MUST have an umblemished no-joint surface, make your own plywood, either by using all veneers or by laminating veneers to a scarphed plywood panel. Vacuum bagging makes it practicable.

[Chan]

Boulter plywood advertises sheets up to 20' and ships anywhere, I'm sure at a cost.

[gert]

Scarfing whole sheet to make comparativly narrow planks is a waste of very expensive material. And difficult. Nest the parts. My current project has planks that are over 25' long, thats 3 set of scarfs each plank, because they were nested first I am probably getting 85% yeild from the 4x8. The widest skarfs were on the garboard, about 18"; the narrowest will be on the shear strake, about 7"; quite easy to do.

Only if the boat had a large flat bottom would I scarf whole sheets.

Us knowing what your building would help ;-)

[Ron Paro]

Scarfing whole sheet to make comparativly narrow planks is a waste of very expensive material. Nest the parts. ...Only if the boat had a large flat bottom would I scarf whole sheets.
Perhaps I am being a little slow thinking this morning, but I don't really see how scarfing the whole sheets causes additional waste. The planks and other parts would still be 'nested' on the scarfed together sheets. Having said that, I do agree that handling plank size parts would be much easier than handling a sheet that is 4' x 16' or longer. Would you still cut the scarf 'ramps' on the full width sheet before cutting out the planks? I would think that if you are cutting the joints with a hand plane, then it would be easier to be consistant across the wider sheet than across a relatively narrow plank. Is that incorrect?

[Bruce Hooke]

Ron,

It would be more efficient because if you are nesting smaller parts (e.g., just sections of planks rather than the whole plank) then you can nest the pieces closer to together in most cases.

If you were planning to scarf the individual planks I think you would be better off cutting the ramps once you had cut out the planks. I don't think it would be a problem keeping the scarf consistent enough to make a good joint. Just mark the start and end of the ramp and plane between those lines. Part of the efficiency of cutting the planks and then scarfing comes from being able to vary where the scarfs fall and how the planks come together, so trying to cut the ramps first would limit your options.

That said, in many cases (if the space is available), I think it would be more time-efficient to scarf the sheets and cut the planks from the full sheet. Cutting one full-width joint would be faster than cutting a whole bunch of narrower joints. However, I don't think there is a hard-and-fast right way to do it. If the boat is hard chine and has relatively wide planks (say 18" to 24") then cutting the planks out first and then scarfing only slightly increases the number of individual joints you have to make and it is easier working with slightly smaller pieces as you are putting together the scarf joint.

So, you've got to weigh how much material you save by scarfing the individual planks versus how much time you save by scarfing full sheets...

[Ron Paro]

Thanks for the clarification Bruce.
I looked at the page that Cyberjag has a link to in the opening post, and he is planning to build the Glen-L 15, which is a V hull with fairly wide planking. Now that I have the benefit of an improved education based on Bruce's answer, I have to agree with scarfing each plank separately for this design. (cutting and gluing)

Best of luck (or whatever it takes) to Cyberjag. That's a nice looking boat to build.

[J P]

Never seen sheet good longer than 12 foot. Marine or other wise.

Paul, 8'x28' waferboard is available. Some of the S.I.P. manufacturers use it. Maybe they'll start making it with that waterproof 'mussel' glue that's being developed.

[Cuyahoga Chuck]

Keeping scrap to a minimum is always a concern when building with expensive marine plywood. If you can keep scrap down to about 15% you are doing good. There seems to be a rule of thumb that producing certain large components, like long curved planks, generate large pieces of scrap. And there is a good possibility the scrap can't be used for other components. If the planks are assembled from small sections these sections can be more readily layed out in a tight formation on the plywood. I've heard that designers now have computer programs that can do this.
When a nesting is done the components are layed out in whatever orientation allows them to be tightly packed together. So, a lot of the edges to be scarfed are nowhere near the edge of the panel.
I found scarfing whole sheets of ply by hand can be a chore. I did a bunch of sheets without roughing out the bevels first. I found my planes lost their edges rather fast so I started each session by honing about five planes up front and was on the last plane when each scarf was completed. I think hacking thru' the glue made the edges go away.
My project required 12' of scarfs. But, one scarf came out bad so I had to cut it and do the whole 4' over.
The benefit of doing whole sheets is you have a factory edge that helps get the halves lined up. When you do components, particularly curved components, there are no straight lines to help orient the pieces. The pieces are oriented using x-y measurements and the scarf has to be cut to fit that orientation.

[gert]

hope this helps

http://farm2.static.flickr.com/1202/577640869_55fe2fa077.jpg

It of coarse depends entirely on the shape of the plank; however doing short scarfs is a whole lot easier than 48" ones.

[Ron Paro]

hope this helps
Well, it's a fact... a picture is worth a thousand words. Thanks for the visual!

So... If I find myself going on to build another ply boat that uses plank shapes, and the plans provide off-sets and a measured drawing for the plank shapes, would I draw out all of the parts on the un-cut, un-scarfed full sheets, and then start cutting? If so, would I account for the scarf joint width by adding the joint width to the end of the segments to be joined? I think this makes sense. Thanks again gert, Chuck, and Bruce!

[gert]

The drawings are never going to provide "plank shapes", that's what the template is for; it's made on the framed boat (there are a lot of assumptions by me here). The scarf area is added when you lay out on the plywood; but you only do them as you go along because the template is an exact model of the required plank (1 of mirrored pair), and you don't actualy know the precise shape of all the planks ahead of time.

[plis]

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It can make thus, too:

Best regards.

[Cyberjag]

Many thanks to all who answered, I don't feel so intimidated by this any more. Elbow grease was mentioned as a primary need, and I have that in abundance. :)