[CAUT] Lever Arm Ratio

Dennis Johnson johnsond at stolaf.edu
Tue Aug 14 14:31:01 MDT 2012


Hi-

All good advice, but while on the subject one issue that always bugged me
about measuring key ratio is that no matter how many times you try
measuring the distance it will never come to exactly the same ratio as
weighing it off.  Go figure, but that's theoretical physics for you. For
some reason weighing off just feels more accurate to me, but I can't
necessarily prove anything. The important thing is being consistent,
obviously.  I like Stanwood's method of wrapping a 10g lead coil around the
angled capstans.  This is very easy and stable.

good luck,

Dennis Johnson
___________________________

On Mon, Aug 13, 2012 at 4:39 PM, McCoy, Alan <amccoy at ewu.edu> wrote:

>  Bob,
>
> I believe that if you measure from the front end of the key to the balance
> rail hole for the front lever arm, and then measure from the balance hole
> to the capstan/wippen contact point for the rear lever arm, and tell them
> how you measured it, you will be giving WNG all the info they need.
>
> Order the wippens with the heels not glued on. Then if you need to put the
> capstans in a different location, you can glue the heels on the wippen
> where they will align with the capstans. Make yourself a capstan boat for
> trying different capstan/heel locations.
>
> Alan McCoy
>
>
> ------------------------------
> *From: *Bob Hull <hullfam5 at yahoo.com>
> *Reply-To: *Bob Hull <hullfam5 at yahoo.com>, CAUTlist <caut at ptg.org>
> *Date: *Thu, 9 Aug 2012 18:57:29 -0700
> *To: *CAUTlist <caut at ptg.org>
>
> *Subject: *[CAUT] Lever Arm Ratio
>
> Hi All!  In measuring a key for the ratio between front lever arm and rear
> lever arm,  I am measuring from the front of the key and the back end of
> the key to the capstan.  However, if the capstan is angled (1927 Steinway
> M) then, does the measurement need to account for the offset created by the
> angled capstan.  In other words, is the length of the lever determined by
> the point on the top of the key at the capstan point of contact with the
> key or the distance from the key end to the contact point with the wippen
> heel?
>
> I am taking these measurements to give to WN&G for the building of a new
> top action stack.
>
> Thanks,
>
> Bob Hull
>
>
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