kneading hammers

[Barbara Richmond]

Oops, that should be 1:00-3:00--or so.
----- Original Message ----- 
From: "Barbara Richmond" <piano57 at insightbb.com>
To: "Pianotech List" <pianotech at ptg.org>
Sent: Wednesday, May 30, 2007 1:33 PM
Subject: Re: kneading hammers


>
> ----- Original Message ----- 
> From: "Rupert Williams" <obliquestrung at yahoo.com>
> To: <pianotech at ptg.org>
> Sent: Wednesday, May 30, 2007 12:12 PM
> Subject: kneading hammers
>
> Greetings Rupert:
>
>> Please could someone give some advice on exactly how
>> to go about kneading hammers as suggested by Alfred
>> Howe in his book on Scientific Piano Tuning and
>> Servicing (1947)?
>
> That's a catchy title!  Can't say I've seen the book (or the movie).  :-)
>
>> He mentions gas pliers, and kneading in alternate
>> directions. Others on this group have in the past
>> explained how they have used vice-grips.
>
> Hmm, I'm not familiar with gas pliers, but I do know what vise-grips are.
>>
>> I would like to know exactly where to apply the
>> pressure, and how much pressure to apply.  Should the
>> felt thickness be reduced by 1/2 or some other
>> fraction?
>
> No, I don't think you want to reduce the felt thickness by 1/2 (whew!). 
> In
> fact, I can't believe that anyone could responsibly say, reduce the felt
> thickness
> by "this much."   It all depends on the hammer, how hard it is, & what 
> your
> goals are.  When I've used vise-grips, the squeeze has been between, say,
> 1:30 and 3:00.  A small imprint is made on the sides and the hammer 
> surface
> is slightly cupped.  Then I proceed to needle the shoulders until the 
> cupping
> is gone.  This is one method to open up or increase the sustain on hard
> hammers.
>>
>> Can the felt be permanently damaged?
>
> Yes.  It is quite possible to ruin hammers with Vise-Grips.
>
>>Is it inherently more harmful than needling?
>
> I wouldn't say so--but yes, if it's over done.  It reduces the amount of
> needling
> one might need to do to get similar results.  I feel the advantage is 
> speed
> and ease--on the right hammers.
>
> Be careful of mis-shaping the hammers.  Unless you really know what you
> are doing, I would be very careful to avoid the strike point or the
> area below  it.  In general, tread very carefully.  Just because a little
> works, it doesn't mean a lot works better.
>
> Off to work.  Good luck!
>
> Barbara Richmond, RPT
> near Peoria, IL
>