Action Geometry

[Richard Brekne]

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Had another question on this Stanwood stuff.   grin.. I hope I get a few more
responses then my last....:)

Ok.. so you have this basic Equation for balance and a bunch of charts for
different Strike Wt vs Strike Wt Ratios.  These differ depending on what
Balance weight specs and all have the same Whippen Balance Weight specs. These
then represent "givens" for the equation of balance.

I am wondering then if you can do the following:

After makeing sure of correct action spread and confirming correct capstan
position and height for that spread, pick the strike weight ratio you want, and
balance weight spec. and then establish the corresponding strike weights for
the hammers. Adjust the whippen radius weight so that together with the actual
key weight ratio (dependent on the capstan position) you get a match to the
spec for the whippen balance weight. That gives you all the numbers for the
equation except the Front weight, which of course you can solve for with these
numbers. After solveing for FW, install weights in the keys to match the
solution. Now it seems to me that what ever discprepency there is in the
resulting real balance weight, and the specified balance weight would be due to
friction. And that you should be able to adjust by dealing with the action
centers and key bushings.

Relocating the capstans would seem only to be neccessary if  the whippen
balance weight spec is too difficult to obtain, and if you cant achieve correct
whippen travel distance when the height of the capstan interesects the magic
line.

This seems like kinda simple really,,, so obviously I am scratching my head
wondering what I am overlooking... grin..

--
Richard Brekne
RPT, N.P.T.F.
Bergen, Norway


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