Reqest: an answer to a poor European gringo

[Susan Kline]

Hi, Joel, 
Dag, André 


<snip>
>Back to the technical stuff.  With regard to different techniques to
>thin the sides of treble hammer shanks, I never worry about that.  The
>sets of grand shanks we use from Renner come with the 18 or so top
>treble shanks already thin.  A quick call to Renner USA will most likely
>identify the appropriate set to order.
>
>Hope this has helped in several ways.
>
>Joel Rappaport
>Round Rock, Texas
>


I wouldn't presume to offer anything to this discussion except questions. 

Looking back over the many good contributions to the hammer shank
discussion, the one by Roger Jolly on Sept. 1 stands out from the rest. I'm
copying it below. 

He describes thinning shanks manually with a spokeshave, and the difference
in his approach is contained in the following statement:

>I usually do both treble sections, gradually taking off less material.

The other methods, whether using jigs and power tools, or ordering shanks
already thinned by the manufacturer, all end up with shanks of uniform
thickness. Why is this considered desirable? In light of what André is
describing about tapping the end of the shank and listening, and the effect
on voicing mentioned by others, why wouldn't we want to thin shanks for an
optimum sound and response, instead of making an abrupt transition from no
thinning to uniformly thin? 

Andre and Stephen Birkett also touch on these questions, but has anyone here
actually done this kind of work?

(Andre:)
>> I know of a german technician (and he is very very good) who uses the tec=
>> hnique of changing timbre/tone (and tonal volume) by scraping.
>> He does not have email though and besides, I am a subscriber to this (Ame=
>> rican List) so why not put my question in front of my American colleagues=
>> 

(Stephen:)
>Well yes...how many of you have "tuned" your bandsaw to get the tension
>right? This idea of tuning shanks is well-known and well-supported by
>theory. One problem to avoid, apart from getting the right flexibility, is
>to have a shank with an undesirable resonant frequency...another source of
>knocking sounds. The shank doesn't just bend, it vibrates itself in a
>complicated superposition of resonant frequencies. 

My 1.2 cents' worth ...

Susan

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Hi ED, 
      Shanks can be slimmed down in the following manner quite quickly and
accurately.  Remove hammmer and shank, clamp to bench with two spring
clamps at the hammer head and flang, remove the required amount of material
with a good old fashioned spoke shave, lightly sand with 120 grit sand
paper, Job done.
  Some cautionary notes The blade needs to sharp, secondly make several
fine cuts and watch out for grain orientation, dont exert too much downward
force. You may pay some dues with the odd broken untill you get the touch.
Practice on an old set of shanks first
> Re; our previous comments hammer mass and touch weight, this tappering
technique is usually reserved for cheaper pianos that have uniform shanks
throughout. The difference in singing tone is well worth the effort. I
usually do both treble sections, gradually taking off less material. I also
do this before removing hammer mass to correct touch weight problems.
Kind regards Roger.
Roger Jolly
University of Saskatchewan
Dept. of Music.

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Susan Kline 
P.O. Box 1651
Philomath, OR 97370
skline@proaxis.com

"As long as you have your feet on the ground, your head is perfectly safe in
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			-- Ashleigh Brilliant