[CAUT] Shank Pitch

[Tim Coates]

I'm not sure what a "scratch" test is.  I can tell if the shanks have  
been thinned.   I usually can tell during the initial voicing if the  
shanks have been sequenced by pitch.  I'm not sure how long Chris has  
been sequencing shanks by pitch but I have been doing it for at least  
twenty years.   Dave, my brother's 6'4" Knabe has the shanks pitch  
sequenced.  Remember that piano?

I explained how to sequence them in a previous post.  It isn't that  
hard to use one shank to compare against other shanks that have had  
material removed.  The only area I care to remove material is from  
the sides because it also affects the lower harmonics created when  
the hammer hits the strings.  I am aware of two things that happen  
when the shank is thinned on the sides:  the shank "doink" sound goes  
up in pitch and the lower harmonics on that particular note become  
stronger.

Tim Coates

On Feb 22, 2008, at 10:36 AM, Porritt, David wrote:

> I'm not being contrary but when you walk up to a piano and play it can
> you tell a difference if the person who hung the hammers didn't  
> tune the
> shanks?
>
> Sincere question.
>
> dp
>
> David M. Porritt, RPT
> dporritt at smu.edu
>
> -----Original Message-----
> From: caut-bounces at ptg.org [mailto:caut-bounces at ptg.org] On Behalf Of
> Chris Solliday
> Sent: Friday, February 22, 2008 9:55 AM
> To: College and University Technicians
> Subject: Re: [CAUT] Shank Pitch
>
> maybe what they are doing at the Bluthner factory is different from  
> what
> I
> do but when I remove material the pitch goes up in my scratch test.
> Perhaps
> this is not the  best test.
> Chris Solliday
> ----- Original Message -----
> From: "Ron Nossaman" <rnossaman at cox.net>
> To: "College and University Technicians" <caut at ptg.org>
> Sent: Friday, February 22, 2008 10:25 AM
> Subject: Re: [CAUT] Shank Pitch
>
>
>>
>>> Chris & all
>>>
>>> I do know that to lower the pitch on a reed organ reed you scrape
>>> material from the bass end of the reed making the mass of the end of
> the
>>> tongue heavier in relation to the overall reed and the pitch goes
> down.
>>> I have never tried it on a hammer shank but I can see where the same
>>> principle would apply.
>>>
>>> Norman Cantrell
>>
>> Hi Norman,
>> In the organ reed, scraping the tip of the reed removes mass,
>> raising pitch. Scraping the base end of the reed decreases
>> stiffness, lowering pitch.
>>
>> Resonant frequency in anything is determined by a combination
>> of stiffness and mass. In the case of hammer shanks, it would
>> appear from the reported results that the loss of mass
>> realized in thinning has a greater affect on "doink" pitch
>> than the loss of stiffness.
>>
>> I don't tune shanks, so I wasn't aware of this. I would have
>> expected the shank pitch to drop. Interesting.
>> Ron N
>
>