popsicle stick engineering

David C. Stanwood stanwood at tiac.net
Sun Oct 29 08:29:49 MST 2006


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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