New glued-veneer boat planking material from Finland

Marketed as Venda-boat plank, the material is all-sliced-veneer construction (not turned veneers), and consists only the species specified when ordering. At the moment, prototype boat is being built at the Ingman College of Crafts and Design (http://www.ingmanedu.fi/), some photos attached here. The material used in the prototype is of full-pine-veneers, and looks stunning. I'm looking forward to hear some test reults from the manufacturer http://www.koivutuote.fi/en/1/company
, Weathering tests, breaking strengths etc. and I'll post them here, if possible.

 

Some more information about Venla

Testing is underway at Savonia University of Applied Science, and the weathering tests show no failures in gluing of veneers with the transparent glue they are using. Strength testing results are due to come within a few weeks, with some comparisons against commonly available plywoods. No wood preservatives are used, so health hazards are minimized during tooling, and common boatbuilding glues and goos stick to it like they do on plain pine.

Marketing and production starts at March, hopefully all the results are then available.

At start, the planks are manufactured in lengths of 2600mm and 3000mm, and widths of 100, 125, 150, 175, 200, 225 and 250 mm, with a possibility of even wider ones on special order.

Plank thicknesses and ply counts are as follows: 6mm/5ply, 9mm/7ply, 12mm/10ply, 15mm/12ply. Inner veneers are of 1,2mm thickness, face veneers of 1,5mm (after final calibrating sanding, a bit less).

Smallest amount of planks they deliver, is "planks for one boat", so there's a great opportunity to order only what you really need for your project.

Jarmo

 

From what I can see in the images, I wouldn't want any of the planks shown, regardless of the adhesive used. It looks to be all slash cut, which is the least dimensionally stable material, you can use for solid wood planking. They obviously should have consulted a real wooden boat builder or NA experienced in wood, before slicing up their log stock. Not even a good cabinet maker would use stock cut like that.

 

Cut direction etc

Dear PAR,

The cutting direction was discussed, when developing the product, and I raised the same issue. Manufacturer told me, that any desired cut direction can be applied for inner or face veneers. As being built up like plywood, with opposing veneer directions, the face veneers cut direction really doesn't add much to plank's dimensional stability.It is NOT solid pine. Anyway, that (direction of cut, radial or tangential) can be specified, when ordering. The only limit will be of the radius of available logs, that being some 350mm at best locally. The idea here is to produce knot-free-pine-plank-looking plywood plank, with no edge-glued face veneers, thus looking like solid pine plank. I know, there are a lot of plywood manufacturers, that deliver their stuff with any desired face veneer, but the board's face is always of edge-glued veneers, developing the "plywood-look". And the inner plys... what do you think of those commonly used lesser-grade turned veneers and their stability?

 

I'll take the bottom 'scrap' board at the bottom Best bit of timber from the tree!.

Unusual to not rotary peel or selectively slice q/sawn stock though. Be interested to see how stable it is over time. Those 'scrap' thicknesses of veneer timber are a bargain if you have a merchant who still does slicing. Regrettably after losing so much of the London ply manufacturing in the 80s' no longer available to me.

What chemical group does the adhesive belong to? The only clear ones I have found so far are epoxy, acrylic and urea formaldehyde. Primarily the colour or lack of, is in the hardener(s), on these groups.

 

I'll be in touch with the manufacturer tomorrow, and check the glue type. I think it could also be melamine-formaldehyde. Rotary cut veneer is all tangential wood, so the most unstable. It also destroys the beauty of the grain pattern, which in this method is preserved.

Jarmo

 

Glue

The type of glue is melamine-urea-formaldehyde, brand name casco MUF 1247.

Jarmo

 

That type of glue in not WBP nor does it satisfy exterior grade plywood standards, surprising.

 

You are right about the WBP. The glue is approved for structural applications for temperatures over 50 deg C, and humidity over 85%. Wet-dry cycles and their effect on shear, tensile and peel strength is being now tested. Temperatures used are not yet declared to me. On epoxies temperatures are, varying with different standards, between 55-80 deg C, eg System Three G-2 is 72 deg C, thus not WBP either, but still is an excellent glue.

Jarmo

 

Thanks for that Jarmo. Looks like it is a more modern version of the Aerolite family of resins, so should be good enough in practice. I certainly know of plenty of dinghies built with this (loosely) type of resin in the 1950s' which are still around today. My own experience is that it is a good adhesive but occassionally if say used on very bendy spars may fail after 30+ years use. Usually straight down the glue line, take it home clean up and reglue...

Rare to fail on a stiffer structure but does not have gap filling properties like epoxy. Cheaper though.

 

More information including prizes and shipping costs at their new website : http://www.vendia.fi/vendia-marine-plank

 

Thanks for the update. Nice product for those seeking the pine finish but superior strength. Not sure about the +/- 50Kg though!

 

I think it's mainly the difference between pine and spruce specific weights, if the planks are made with spruce inner veneers. The wood is harvested from similar growth areas (soil, light etc.) that the wood itself should not have differences that big. Here's a pic from a boat-building course, where six of these boats were built. They told, that the plank is easy to plane and bends nicely. And takes impregnation as well as solid pine.

 

WoodenBoat article

There's an article about Vendia Marine Plank in the latest WoodenBoat -magazine. Author is professor emeritus Dr Richard Jagels of university of Maine. Link to the article: https://docs.google.com/file/d/0BzDjSGBYI5iBcHNzamZoa1ZoSmc/edit?pli=1

 

Oh yea that stuff, even if the veneers are flat sawn when you glue say 7 layers together the plank becomes stronger and more stable than solid wood of the same dimension. And providing that the veneers are not from the same flitch it will be much less prone to splitting and will probably bend in fairer. When we make high end interior or exterior doors we often start with cores made up of glued up strips and then veneer them. When the rails and styles are laminated they become very stable and these doors almost never warp or twist.(a whole lot less warranty work) This works very well on exterior doors where there is always a difference in outside and inside temps and humidity! I can also see using these planks as chines or other light framing where there are lots of fastenings going in. No splitting! Maybe they could send me 300bdf so I can test them. I need a new skiff! What? I remember the constant camber building method where they were using veneers from faster growing and smaller trees. Maybe these planks could be made up with wood from farm grown trees. Maybe someday? Any how, seems like a good idea............................................g