[CAUT] Lighter Touchweight

[Jon Page]

>Not sure I understand what you mean here.  Putting aside the jack knuckle
>interface angle, why would the advantage of shimming out the wippen be lost
>at the knuckle?

Because the knuckle is moved further out on the repetition lever also.
Moving the rail back, increases the distance from the center pin to the
capstan on the wippen support (+)  but it also increases the distance
from the cp to the knuckle (-). It's a wash.

Moving the stack alters only the input dimension on the wip ratio.

In Barbars's case, moving the stack forwards increases the wippen's 
ratio and it will regulate with a longer blow distance but will also 
increase touchweight and friction.

In the Baldwin grand case, moving the stack back will lower the 
wippen's ratio and
will lower the touchweight and friction.

Touchweight and FW have to be taken into consideration as well as the amount
of room to move the keyframe fore or aft between the fallboard and 
keyslip because
if one moves the stack, the keyframe needs to be relocated to 
maintain strike point.

I'm doing this right now on a Samick. Done it many times with success 
because the stack
isn't always in the right spot to begin with. Even treble to bass 
positioning of the capstan
on the cushion. I find it's usually tha the capstan is further back 
on the cushion than the treble causing the wippen ratio to be uneven 
across the compass.

>Moving the wippen rail is only to align the centers. There is no leverage gain
>as one might think by moving the rail back because the advantage you gain
>in regards to the capstan is lost at the knuckle. Whereas moving the stack
>back increases the input dimension without increasing the output
>thereby lowering the ratio.
-- 

Regards,

Jon Page
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