[pianotech] Glue for hammers - question

[David Ilvedson]

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