popsicle stick engineering

Kent Swafford kswafford at gmail.com
Sun Oct 29 12:09:57 MST 2006


5.6? This is on a Steinway B that currently has a SWR of 6.5 with  
17mm Steinway shanks.

Kent


On Oct 29, 2006, at 9:29 AM, David C. Stanwood wrote:

> Hi Kent,
>
> Strike Weight ratios will always vary note to note.  Better to hit  
> an average Strike Weight Ratio level using a straight capstan  
> line.  This means finding sample capstan positions across the key  
> board that hit the target SWR.  When you hold a straight edge to  
> the sample marks they will not all be exactly on the line.  Strike  
> you new capstan line such that it comes closest to all the marks.   
> Let the key ratio be what ever it is to be to make your target  
> SWR.  What is your target SWR?
>
> David S
>
>> Of course. It was strike weight ratio to which I intended to refer in
>> my original post. I assumed one wants both ratios to be as uniform
>> across the keyboard as one can manage, especially on a piano that is
>> likely to have new parts again in the future. Right?
>>
>>> Kent
>>>
>>> Have you considered the fact that if you move the capstan to make  
>>> the key ratio change your changing the wippen ratio as well?  A  
>>> more complete picture of the effects from moving a capstan line  
>>> are found by seeing what kind of strike weight ratio a given  
>>> capstan position will yield.
>>>
>>> Helpfully hopefully,
>>>
>>> David Stanwood
>>>
>>>>
>>>> OK, so you establish a new capstan line. Excellent. As long as I'm
>>>> checking and controlling the key ratio, I'll guard against
>>>> perpetuating mistakes in the original drilling. Thanks, I  
>>>> appreciate it.
>>>>
>>>>
>>>> Kent
>
>



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