[pianotech] Glue for hammers - question

[pmc033 at earthlink.net]

Ed:
	 Having flexibility in the glue joint is going to affect the system,
either a little or a lot.  Which one I would guess would depend upon the
degree of flexibility.  If it  doesn't matter that there's flexibility in
the glue joint, then why do loose hammers emit a different tone?  Ok,
that's an extreme case, but is it not a matter of degree?  In that case,
the hammers are still disconnected from the jack and continue forward from
momentum.  Let's hang some hammers with different glues, different amounts
of clearance in the joint, shanks that are/are not knurled, and see what is
the result.  I would guess that there will be some slight difference.  For
the sake of this thread, a direct comparison would be very informative.
	My take.
	Paul McCloud
	San Diego


> [Original Message]
> From: Ed  Sutton <ed440 at mindspring.com>
> To: David Ilvedson <ilvey at sbcglobal.net>; <pianotech at ptg.org>
> Date: 06/08/2009 3:06:19 AM
> Subject: Re: [pianotech] Glue for hammers - question
>
> David-
>
> A steel hammer would strike an even firmer blow. How would it sound?
> Would a gold hammer sound "golden?"
> Does a wool hammer sound "wooly?"
>
> You could find out: hang a hammer with CA glue, which is very hard, and
hang 
> its neighbor with PVC-E, which is very flexible. Do some blindfold tests, 
> asking people to describe the differences in sound.
>
> My guess is that the flexing of the hammer shank, and the intended 
> flexibility of the wool hammer, exceed by far any difference in
flexibility 
> in the glue joint. And please remember that the jack is not driving the 
> hammer at the moment it contacts the string, the hammer is moving because
of 
> its own inertia. It is not the same as a hammer driving a nail, it is
more 
> like a mallet striking a gong.
>
> I respect very much your concern for getting every detail as correct as 
> possible, but feel we need to examine carefully every idea of correctness
we 
> can test. Poetic understanding can help us attain higher levels of 
> perception, but it can also lead us into wonderful blind alleys. We need
to 
> be aware of seductive words. I knew someone who insisted on putting the 
> cream into his coffee cup first "so that the coffee would warm up the 
> cream."
>
> Ed
>
>
> ----- Original Message ----- 
> From: "David Ilvedson" <ilvey at sbcglobal.net>
> To: <pianotech at ptg.org>
> Sent: Monday, June 08, 2009 12:34 AM
> Subject: Re: [pianotech] Glue for hammers - question
>
>
> > It's all those little things that make the difference, imho.   To me it 
> > makes sense that hammer would hit the string with a firmer strike if
the 
> > glue joint did not flex an iota...
> >
> > David Ilvedson, RPT
> > Pacifica, CA  94044
> >
> > ----- Original message ----------------------------------------
> > From: "Ron Nossaman" <rnossaman at cox.net>
> > To: ed440 at mindspring.com; pianotech at ptg.org
> > Received: 6/7/2009 7:19:06 PM
> > Subject: Re: [pianotech] Glue for hammers - question
> >
> >
> >>Ed Sutton wrote:
> >>> I am curious what the arguments or evidence may be for the tonal
> >>> superiority of a rock solid hammer to shank joint.
> >>>
> >>> A rattling joint is not good, but what is lost if there is a small
> >>> degree of flexibility in the glue?
> >>>
> >>> The hammer felt itself is definitely flexible by design, and not rock 
> >>> hard.
> >>>
> >>> The hammer is not being driven when it reaches the string, it is
moving
> >>> by its own inertia.
> >>>
> >>> It is generally considered desirable that the hammer stay in contact
> >>> with the string a period of time, and not rebound instantly.
> >>>
> >>> Eugene Thorndahl, the former glue chemist at Peter Cooper, suggested
to
> >>> me that a small amount of glycerine added to hide glue would give it a
> >>> little more flexibility, and produce a more dependable hammer joint,
but
> >>> he was addressing the strength of the joint under stress, not acoustic
> >>> issues.
> >>>
> >>> Ed Sutton
> >
> >>And don't forget the action bedding, and the flange pinning,
> >>and the backcheck height (2mm below the tail at drop), and the
> >>front rail punchings, and the coupling of the casters to the
> >>floor, and the room acoustics, and the front leading in the
> >>keys (for inertia control), and the hammer needling and
> >>lacquer application techniques and locations, and the duplex
> >>scale tuning, and, of course, the A-4 pitch and temperament
> >>choice. Why, with all this sterling ammunition, are these
> >>things still being endlessly debated as if they were real? All
> >>evidence considered, it doesn't seem to much matter, since
> >>it's not apparently possible to make the right set of choices
> >>in *any* specific situation.
> >
> >>If all this nonsense still hasn't been hashed out by now in
> >>the real world of day to day piano service, what's the point?
> >>Ron N
> >
> > 
>