Piano World Home Page Forums Our Most Popular Forums Digital Pianos - Electronic Pianos - Synths & Keyboards Why does Kawai put plastic in wood pianos & wood in plastic?

Kawai is widely criticized (especially by the Steinway/Boston bunch) on the acoustic piano forum for putting plastic actions into their wooden pianos. On the digital side, Kawai brags about putting wooden keyboards into their plastic, digital pianos.

What gives?

Woudn't it make more sense to keep the plastic pianos plastic and the wooden ones wooden?

I'm happy that they do it this way since I only own a DP from KAWAI...

BTW, their "plastic pianos" are not really plastic pianos. They consist of lots of wood, only they have lots of electronic stuff inside. I like the smell of the wooden keyboard.

I suggest to ask them directly, I personally have no idea!

ABS action parts are used inside all Kawai acoustic pianos because they are stronger, lighter, and more climatically stable than traditional wooden equivalents.

Wooden keys are used inside selected Kawai digital pianos in order to recreate the weight and feel of an acoustic piano keyboard as closely as possible.

I hope this answers your question.

Cheers,
James
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This implies that Kawai's acoustic keys dont feel like an acoustic piano should. If they really wanted to recreate the weight and feel of an acoustic piano in their digitals, wouldnt they just use the same key materials that they use in their acoustics? This does seem backwards.

Interesting reading, Jeff. Thanks for the link.

We have to remember we are talking about wood and plastic in completely different parts of the piano. Acoustic Kawais have wooden keys just like their DP models that have wooden keys. The plastic used in the acoustic models is not in the keyboard itself but the action parts.

My understanding from researching on this is that many techs nowadays agree that the plastic parts used in Kawais acoustic action are very reliable and of great quality, and they help keep pianos well regulated. I think Larry Fine's guide talks a little about that on their review of Kawai's acoustics.

I'm sorry, I'm not sure I follow you.



Yes, this is precisely the point. Wooden keys are used in acoustic pianos, therefore in order to recreate the weight and feel most accurately, some Kawai DPs also use long wooden keys.

I wonder if you're perhaps confusing the keyboard of an acoustic piano (wood) with other parts of the action (a combination of wood, metal, and in the case of Kawai, ABS)?

Kind regards,
James
x

It would make a lot LESS sense to limit your designs to using only one kind of meterial. Why not use what is best for each part. Wood is a great material, it's cheap, strong, and is a little bit springy but with good internal damping. I think Kawai puts some plastic composite parts in their acoustic pianos because they can be much stronger and ligher then wood parts they replace.

In both lines of pianos I think they use a mix of parts

So, in other words, Kawai is the only brand that actually uses the best material in the best place to achieve superior performance, whether on their acoustic pianos or their top to the line digitals.

Yes I was. Sorry!

From what I understand, Mason & Hamlin is now using, at least in some of their pianos, Wessell, Nickel & Gross actions that have carbon fiber parts, similar to Kawai's approach. They have an ad on this page. However, Mason & Hamlin does not make Digitals.

You're confusing two different things.

KEYS
1. All acoustic pianos have wooden keys. They key TOPS are generally plastic, save for those surviving ones with ivory.

2. Most digital pianos have plastic keys. Plastic through and through. But some have wood bodies, with plastic key tops (such as the Kawais mentioned above). In these cases, the digital is much like an acoustic.

ACTION
3. Most parts inside the action of a traditional acoustic (grand or vertical) piano are wooden (except for metal frame rails, flanges, screws, etc). Some decades ago, manufacturers began using plastic for the wippens, jacks, stickers, and selected other parts. Kawai is even using carbon-fiber in some cases.

4. But none of those action parts even exist in a digital piano (except for those few pianos --- Avant Grand --- that have the action of an acoustic). A digital has parts that are analogous to those found in an acoustic action ... such as simulated/weighted hammers and the supporting infrastructure. These are a mix of plastic and metal.

"...Wood is a great material, it's cheap, strong, and is a little bit springy but with good internal damping. I think Kawai puts some plastic composite parts in their acoustic pianos because they can be much stronger and ligher then wood parts they replace...."

Not to be too argumentative, Chris, but I don't think the wood they use in pianos is all that cheap... not these days, and not with the process of seasoning and selection they have to use.

It's true that the action parts Kawai and WNG use are lighter, stronger, and more responsive. The additional problem with wood action parts is that as they alternately swell and shrink with humidity changes, the wood fibers held in place by screws are alternately crushed and shrunk, which lets the screws loosen up, the wood parts warp and go out of alignment, etc.

Nothing against wood, though--- I love wood. The miracle engineering material.

Anyone criticizing Kawai's use of ABS Styran composite ('plastic') in 2010 only shows a) that they are ignorant or b) that they are a dishonest salesperson using competition bashing to get a sale. Kawai's actions have passed the test of time (for some 30 years) and any technician worth his salt acknowledges them as a real innovation.

Other than the promotional stuff on the web, I don't know anything about Kawai actions.

But if I were a piano manufacturer I'd be all over plastics for the key and damper actions. It would be kind of wild to order replacement parts that just drop right in.

Wood, even "exotic" wood is not expensive. I looked up some priced at a local retail shop that sell specialty woods. Teak is $30 and Cherry is $10 per borad foot. That is 144 cubic inches. Compare that to the price of epoxy. Even teak is cheaper. The cheapest platic I can think of might be polyester but even that is more expensice then cherry by volume. Compare to the price of 144 cu in of steel, wood is still less exppnasive and steel is a "cheap" metal.

What makes wood expensive is the labor it takes to machine and assemble and finish it.

Okay. But you won't find much teak or cherry in a piano. Further, some of the wood used in quality pianos (esp. maple for bridges and spruce for soundboards) is of better quality than what you're looking at. The better manufacturers are very picky about the wood used in critical components. The wood they reject becomes fine furniture.

And, yes, the labor for working wood is expensive.