[pianotech] measuring action ratios

[David Love]

The longer it is the less the margin of error in measuring. But at a certain
point the jack tender hits the let-off button and the hammer travel starts
to change. 

David Love
www.davidlovepianos.com


-----Original Message-----
From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf
Of Joseph Garrett
Sent: Tuesday, January 15, 2013 10:39 PM
To: pianotech
Subject: Re: [pianotech] measuring action ratios

A simple block of wood with an extension (mine is a machine screw) that lays
across the keys and that depresses a key exactly 6 mm whereby you then
measure the amount of hammer travel and divide that by six to give the
action ratio. It's been posted several times on the list by Dale Erwin and
others. I'll post some pictures if I can find one.
 
David,
Ah, yes. I do recall that now. BTW, thanks for the pics. 
Not sure why it's 6 mm, tho. Why not 5 mm, which is 1/2 of most key dips,
(well sorta<G) Best, Joe


Joe Garrett, R.P.T.
Captain of the Tool Police
Squares R I