Action Ratio and Dip and Blow and Etc.

[Jon Page]

>  > Is the wippen flange centers at a good height? Usually 2 1/2" below the
>  > HCH.
>I'm trying to imagine what HCH could be - and am failing. What is HCH?


Hammer Center Height.

Other alignments to consider: Action spread, knuckle core to jack center.

The first photo with the knuckle at 16 mm had the core lined up properly
with the jack center.  (Are those lead weights in the felt?) Is that 
the blow distance?

On the relocated knuckle the jack center is too far forwards of the 
knuckle core.
Can you increase the spread? Where does the rep lever contact the upstop screw,
where does the jack contact the let off button. Is there room to move?

With that height of a heel extension the magic line is out the window.

More importantly in your experimentation, where does the jack end up?
When all is said and done, the jack needs to be in close proximity to the
knuckle at the end of the keystroke.

Another consideration to really confound matters: stack relocation.
Since the hammers are not on, the stack could be located further back
a few mm. Then the hammers might have to be installed at a shorter radius.
I've corrected a few problems by moving the stack back on quite a few actions.
This would cause an increase in dip and lower touchweight.

Fun, ain't it?
-- 

Regards,

Jon Page
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