[pianotech] Action ratio....

[Joseph Garrett]

David asked:
"All -
 
Asked this question on the wrong list???.
 
 
I have enjoyed very much the ratio discussions, especially the ongoing one
as few weeks ago ( key in , key out etc) that Nick and several others
contributed to. My question-
 
What is a practical way to actually take those measurements, especially the
key measurements? Many times I will put a long center pin in a wip flange,
tie off some carpet thread and use that to look at the lines of compliance
for key- wip- capstan, but how to measure key in- key out accurately and
predictably? Calipers? Rulers? Also, I have seen a couple of ways to
measure for key in - from balance point to the end of the keytop, from
balance point to where the front pin enters the key. This relates some to
what Fred was posting, but thought another topic would not muddy things up.
 
Thanks for this interesting discussion"
 
David,
I have invented a tool that measures the Magic Line. Presently, I am not
offering them for sale because I've not found a machinist that is willing
to do it w/o reinventing the wheel!<G> :-( Perhaps I'll do a run of them in
the near future. With the Magic Line Tool, you could get the key
measurements and still have a free hand.<G>
Just so's ya know.
Regards,
Joe


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