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Rare and very expensive. Sawing veneers (along with the necessary post-processing) to a uniform 1 mm (or less) in thickness is very difficult. Especially with softwoods.

ddf

Lothar Thomma and others have long proven that laminated boards can have same or similar sound qualities - IF properly engineered.

The industry has been slow to adopt this simply because of marketing reasons.

I happen to be one who has expressed my opinion to same effect before.

"Laminated" for the most part, remains a dirty word almost like "clean diesel"..

The more clever ones among the manufacturers have long called their soundboards simply "all spruce"

Meaning: "all three sheets are made off spruce"...ha ha
[no names mentioned to protect the innocent...]

Norbert

Del, glad your getting some information out there. I think consistency is a big plus in laminated boards, especially for large production pianos. As spruce is becoming less available, the ability to use off-color pieces in the interior is a plus too.

Have you tried any other woods besides the traditional spruce? What is the impact of the adhesive and pressure during lamination?

I have not tried other wood species but others have. Baldwin, for a time, used poplar and bass.

The legendary StoryTone soundboard was made of what they called "mahogany." It was actually lauan -- a wood that was euphemistically called Philippian mahogany at the time.

Any number of woods could be used as long as attention was paid to their stiffness and mass characteristics.

The biggest single layup problem that I'm aware of is an inadequate amount of adhesive. Over the years some panel manufacturers have attempted to skimp on the adhesive and this can lead to delamination later on. Other problems are out-of-date adhesive, incorrect heat (either too high or too low), improperly dried veneers or core stock, etc. In other words, the same rules that apply for good wood processing still apply.

ddf

Greetings, I think this subset of what you wrote is the key point.

The other advantages being stated are not so clear in my opinion.

I don't know if the thinking has advanced, but in some previous thread, I pointed out that for a given moisture absorption, laminates are actually under more stress because the laminates are constrained by the axial grain components of the wood layers they are adhered to, such that wood-cellular compression damage would occur through plastic deformation or fatigue rather than out of plane bending (piano going out of tune). The response, I recall, was that there are moisture barrier films. But, moisture barriers films should be possible to apply on conventional boards too, giving them that equal advantage if it so desired.

I would say another disadvantage of laminate boards is that they are more complicated, which means more things can go wrong. Secondly, unlike conventional boards, one cannot inspect the details of construction as easily to see if those moisture barrier films will be successful, correct processing of the new adhesives, uniformity of wood used in the core such that anticipated piano-to-piano reproducibility will be realized, and so forth.

That said, there is no reason to think laminate sound boards cannot sound good.. I wish them all the success.

Best wishes-

There areonly two places that make those sawed veener, here is a video showing the 2 saw and the woods

The saw was an ivory saw, modified, enlarged . Most parts are in wood to absorb vibrations.
They say the spend a lot of time on sharpening the blades

They can saw up to 1 meter large.

I think the veneers are thicker than 1 mm most often, 12 or 13/10 mm.

http://www.wat.tv/video/bois-montant-version-finale-fb92_2frvr_.html

Have you actually read the article? Some of your concerns are addressed with the discussion about the face-to-core grain orientation being used in modern laminated soundboard panels.

All soundboards are compromises of one sort or another. It is true that the face and core veneers are affected by changes in moisture content. They are, after all, still made of wood. The perpendicular-to-grain compression and tensile stresses are primarily confined to the core by virtue of its thickness. Because they are very thin the face veneers are not subject to appreciable stress failure. The cellular structure of the wood is affected by changes in moisture content but experience has shown that the structural integrity of both the core and the face veneers is not adversely affected. At least not within the temperature and humidity swings normally encountered in the average home. Rather, laminated soundboard panels have proven to be both more stable and more durable through climate extremes than their solid spruce counterparts.

Many piano makers specify a somewhat higher ambient moisture content (compared to solid spruce construction) when their panels are glued up so they start out much closer to the average moisture content found in typical homes than is common with solid wood panels. This reduces the compression peaks without introducing excessive tensile stresses. Several decades of experience with high quality and high performance laminated soundboard panels have shown that your concerns are really non issues. I don’t know of any company that, after switching from solid soundboard panels to laminated soundboard panels, has found its warrantee costs going up. Quite the opposite, they go down.

(By the way, it is a common misconception that modern laminated soundboard panels do not go through any dimensional changes with fluctuations in moisture content. Only a pure “plywood” panel—i.e., a panel with the face veneers at 90° to the core—approaches absolute stability. While this construction was common years ago, modern laminated soundboard panels—as noted in the article—are typically laid up with crossing angles somewhere between 45° and 15°. A three-ply panel with the faces laid up at 0° to the core would act quite like a “solid spruce” soundboard panel. As the crossing angles increase the panel acts less like a solid spruce panel and more like a plywood panel. Everything is a compromise. A panel laid up at 45° will be dimensionally more stable than one laid up at 15° but a panel laid up at 15° will perform more like a solid spruce panel.)



You are right in theory but this has not proven to be an issue in practice. Piano manufacturers routinely tear laminated soundboard panels apart to verify that their suppliers are giving them panels that meet their specifications. There are now tens, if not hundreds of thousands of pianos in service with laminated soundboards. If there were endemic problems with this construction I would have expected them to have surfaced by now. Indeed, performance consistency and structural integrity are among the advantages of this construction.

ddf

That video is hard going if you don't understand French...

There are several companies making powered frame saws. One of them can be seen here:
http://www.ogden-group.com.php53-2....oads/documents/Eco-Power/EcoPowerWeb.pdf

This particular machine—Ogden—specifies a minimum veneer thickness of 2.0 mm. I've talked to owners who claim to have made their own blade spacers and who have been able to go some thinner than this.

All veneer saws share some common problems: First, they are very slow. Even sawing multiple veneers in a single pass—as with the Ogden—the saws cut slowly so the time investment is considerable. This raises the cost for something like production laminated soundboards to a prohibitive level.

Second, they are inefficient (in their use of raw material) and just about as much wood ends up as sawdust. This rather defeats the goal of preserving spruce forests.

Third, even with careful "tweaking" it is difficult to saw veneers thin enough for soundboard face veneers. As well, sawn veneers, by their nature, have rough surfaces—all of these machines are, after all, simply powered frame saws—and have to be sanded prior to gluing and this wastes more wood and takes more time.

ddf

The difference is in the colors and the deepness of the shades , the figures of the wood, that is why they are used for furniture, marquetry, decoration.

In the video he shows at some point the difference between sawed veener and cut veener, by spraying some alcohol on it.

The figures in the wood are more contrasted and more colored with the sawed one (at the back)

When I think that on our old pianos there is plenty of them, on Pleyel even gluing together 2 pieces of standard cut veneer does not make the original thickness.


I think they are best finished with the classical "French polishing" process, with shellac and alcohol .
Then the fine sanding is done at the same time the pore is closed , at the beginning of the job, using pumice and alcohol to polish the surface and create the sealer, that process is keeping the deepness as the fibers are not crushed.

Yes, sawn veneers have many wonderful characteristics. They are still completely impractical for production piano manufacturing.

ddf

There's a Story & Clarke console circa 1970 (#457855) that I play at a private club the first Wednesday of every other month. It seems to me to be a fairly ordinary old beater piano.

So then the adhesives don't significantly impede the movement of moisture into and out of the core, right? Might it be possible to find adhesives that do block water? If so, would that be a good idea or a bad one?

Sorry, this might sound a naïve question, but how exactly would you define downbearing? Is it the same as crown?

Hi David,

I don't know much about piano technology, but I think downbearing and crown are related...

You can check the downbearing with a downbearing gauge; you place the gauge on the center of the string on the bridge, and measure the gap/distance between the gauge and string near the bridge.

Downbearing is the force of the string tension pushing down on the bridge, which transfers the sound from the string through the bridge and into the soundboard.

You use a string to measure the crown by stretching the string tight from one side of the soundboard to the other on the bottom side, and measure the gap between the string and soundboard in the center of the soundboard.

If the soundboard has little or no crown, it may well have little or no downbearing, which could affect the transfer of energy from the string to the soundboard, affecting tone.

Of course, I could be wrong.

Rick

just a little correction to make regarding the Pleyel laminated soundboards made in the early 1800's

They were veneered with whatever veneer was used on the case of the piano, which could have been Brazilian Rosewood, 'Cuban' Mahogany or other varieties used in those days for furniture.

The selling point was that they were 'guaranteed not to crack'

the soundboards that were veneered also tended to be a bit thinner to their normal counterparts, probably because of the increased resistance to splitting and had a cleaner sound, in my experience.

one thing that Laminated Soundboards could do to improve the lightness to stiffness ratio could be to substitute the middle section with a lighter and more porous wood.

I had a set of 3-ply drums which had the middle layer made of a softwood with hardwood veneer.. sounded good

I mean, if you use hardwood on the outside and then a very light wood in the centre, you would get the stiffness but lightness as well..

might sound awful but maybe it wouldn't.. say in the bass section

No. The common adhesives used for this purpose are not vapor resistant. The only adhesive I'm aware of that could form an effective vapor barrier is epoxy. Using epoxy would slow the process and drive up the cost considerably. I'm not sure just what, if any, benefit would be derived with this. I can think of some potential theoretical advantages but I rather suspect they would be just than -- theoretical.

ddf

No, I did not say much about sound quality in this article. It was really outside the scope of the article. What I wanted to address was the unwarranted confusion and fears that surround pianos using laminated soundboard panels.

Performance—timbre or tone quality, action performance, etc.—are things the consumer can readily evaluate for himself or herself. The piano either sounds good to their ear or it does not. If the piano does not sound good then how it is constructed is really moot; the buyer should move on. If it does sound good then I want the reader to understand that laminated soundboard construction is a positive feature and not something to be afraid of. It is up to the buyer to define "good."

ddf

Thank you for the correction. Now, if I just remember it....

ddf