Ratio question

[Richard Brekne]

Yes.... exactly Jon.  Which is why I wondered about what Phil was really 
asking and why.  Obviouslym measured from the key front a 1mm increase 
there will result in a 1 mm increase in dip.... and giving Phil benefit 
of the doubt as is my want I had to scratch my head at his querry.  We 
are still waiting for zee response :)

Cheers... nicely put post btw...

RicB


    If you don't measure the dip at the front of the key (where it is 1:1)
    you have to consider the length of the key and the angle formed from
    pivoting on the balance rail and how far back from the front you
    measure.

    For instance, my dip block measures 48 mm in length,
    9.9 mm (.390") at the front tapering to 8.4 mm.

    That's roughly .19 mm decrease for each 6 mm moved back.

    But it is much too complicated for the task involved. Not only do you
    have to consider the angle of the key at dip, you have to consider
    the rate of height change on the risen key since it is pivoted at the
    back rail.
    So the height measured 6 mm back on that key will be ever so
    minutely less than the +1mm due to the longer radius (probably half
    the rate of change as the 'dipped' key due to twice the radius).

    Keep life simple, measure dip at the front, 1:1.

    The amount of dip is dependant on what is required for regulation
    but that's a different topic.
    -- 

    Regards,

    Jon Page