Feltmakers vs. Hammermakers

Delwin D Fandrich pianobuilders@olynet.com
Thu Jan 11 09:53 MST 2001


----- Original Message -----
From: "Horace Greeley" <hgreeley@stanford.edu>
To: <caut@ptg.org>
Sent: January 11, 2001 12:03 AM
Subject: Re: Steinway Hammers


> I remember a class you gave some years ago on hammers/etc.  Would you
> please shed some light on manufacturing issues?
-------------------------------------------------

Oh, yes. I've been reading all the stuff about hammers and hammer felts,
I've just been avoiding getting into it because it's just going to bring on
another rant and I've already had two this year. And I don't know how much
more trouble I want to get into just now.

As may be...Why is it that every time we end up with something we don't
quite like in this industry, or that we don't understand, we blame it on
some poor animal that lived a hundred years ago, but is now going, or has
already gone, extinct? Or we attribute it to the characteristics of some
esoteric material that hasn't been around for generations and that we'll
probably never see again. Or to some process that we don't quite understand
because there are no records of it and we don't know much about because
nobody has ever seen it or talked to anyone who did it but it must have been
done because the wonderful old pianos sounded wonderful and they don't sound
wonderful any more. We'll do most anything except do the basic research
necessary to understand what is really going on in the piano.

In this case we're going to blame some poor sheep for dying out. And the
feltmaker who is forgetting how to make felt. We just can't get piano
hammers that make any musical sense because some breed of sheep is no longer
with us. We can't get decent hammers because the felt don't know how to make
felt any more. Phooey!

The feltmakers I know have more knowledge about wool and about the process
of making felt than their predecessors ever dreamed of knowing. Indeed, they
have so much control over the process that they can deliver felt with just
about any characteristics anyone can imagine and for purposes you and I
can't even imagine. Want to make a felt hammer hard enough to pound nails?
They can make it. In fact, some piano hammers are coming pretty close...

The problem is not with the feltmakers, at least not that I can see. It is
with the felt users. It should be fairly well known by now what it takes to
make a good piano hammer -- that is, a musical piano hammer. And, I'm sure
it is. It's just that what it takes to make a good hammer (musically) might
not be -- no, it definitely is not -- the easiest to do in production.

For example, hammer felt is made with the wool fibers biased in one of two
directions. As you view the finished hammer, the predominate bias of the
felt fiber is going to either go around the parameter of the hammer or it is
going to go across the hammer -- i.e., from side-to-side. Now, it's been
understood since the dawn of time that having the wool fibers biased to run
around the parameter of the hammer makes for a better performing hammer, but
it is some harder to press. The felt strip get some squirrelly in the press
and wants to wiggle out of the caul. This means that the press operator
actually has to pay attention to what is going on in the press and might not
have time to make his or her production quota and still get each set of
hammer just right. We can easily solve that little problem by going back to
the feltmaker and having them change the bias of the felt lay. That the
resulting product is no longer the best sounding hammer is now the fault of
the feltmaker? I don't think so.

Is it the fault of the press operator? Again, I don't think so. The press
operator doesn't really know anything at all about the requirements of the
finished product that he/she is making. All the press operator knows -- and
they know this very well, they are experts on the subject -- is how a
certain material works in their particular phase of piano building. But,
when he/she goes to his or her supervisor and complains about not being able
to make their production quota because of the difficulties they have
pressing a certain type of felt, it is passed on as if the felt were at
fault. Sorry, but no -- piano making isn't always easy. And sometimes the
hard way is the way it must be if we are going to have great sounding
pianos. Even if it does add $0.25 to the cost of the final product.

Even the ease -- or lack thereof -- of shaping hammers is being blamed on
the feltmaker. All the feltmaker does is supply a very large sheet of felt
that is felted, pressed, thicknessed, cut and tapered to the hammer
manufacturers specifications. The hammermaker takes it from there. The
hammermaker cuts this sheet into a number of tapered, wedge-shaped strips.
These strips are placed into the hammer press and pressed around the hammer
molding (and inner felt, if used). The idea is that the wood molding should
come down exactly in the middle of this wedge strip -- that is, the finished
hammer should be symmetrical with an equal amount of felt on each side of
the molding. If the felt wedge slips because the operator doesn't have time
to pay attention to the process, the finished hammer will not be
symmetrical. No problem, we'll just machine file it to shape. But, what if
the hammer doesn't want to file to shape? What if the sandpaper wants to
bring up 'layers' of felt that want to keep following the un-symmetrical
shape of the hammer strip? No problem with this, either. We'll just go back
to the feltmaker and have him leave the sheets of felt in the pounder some
longer and felt the stuff more. In other words, we'll end up with a more
felted felt. This makes the felt much more homogenous and takes away the
layered effect of the traditional old-time piano hammer. No matter that it
also takes away most of the natural resilience of the hammer. Nobody much
cares -- or remembers --about that anyway. Technology marches on. Besides,
our soundboards are so stiff and heavy, and our rims are so floppy that we
can use all the density and mass we can get in our hammers. Got to make
those pianos powerful you know. How else can we destroy the hearing of
another generation of piano players and technicians? How else can we sell
pianos if they are not powerful. So what if they are not musical? That's the
dealers problem. So what if they are not voiceable? That's the technicians
problem. Just so people keep buying pianos.

Now, I ask you -- is any of this the felt makers fault? I don't think so. I
suppose we could blame them for their on-going research efforts into the
basic characteristics of wool and the process of making wool felt. It is
that knowledge gained through this research that enables them to give the
hammer makers just what the hammermakers want. It's too bad if that
material -- I hesitate to call it hammer felt -- no longer makes good piano
hammers.

And I haven't even gotten in all the tortures the poor felt is put through
once the hammermaker gets hold of it. The temperatures used in the 'modern'
hammer press. The pressures used. And, what has to be done to the felt to
make it possible to make some of the monstrosities that pass for piano
hammers these days.

So, don't blame the feltmaker. They know whereof they speak. It is our own
industry that is to blame. "We have met the enemy, and they is us."

Regards to all,

Del



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