[pianotech] action ratio

[Steve Blasyak]

Hey now to all,

I have a quetion regarding action ratio. More specically, what would be the
possible cause(s) of an action ratio that is a bit out of wack for lack of a
better term.

Now before I start a big debate, I just wanted any participants to know that
chances are I would not be regulating this piano because the work simply
would exceed the pianos worth.

I purchased Dale Erwin's action ratio jig some time ago and have not had
much of a chance to use it. This patient seemed to be a good test dummy even
though it was a studio upright. The key dip was extreme, way past 3/8ths,
hammer blow about normal 1 3/4".

Just for the heck of it I tried the to analyze the action ratio to see what
I could come up with if I were to decide regulate. To my surprise the piano
came up with something far less than a 5/1 ratio. Not sure if I did my
calculations right but I came up with something between 4.2 and 4.3. To
regulate with this action ratio using a 3/8ths dip, I would have to have a
blow distance of slightly more that 11/2" correct?

So my question is, what would cause this ratio to be so low? Following past
threads on this list regarding Grands, it could be improper hammer bore,
capstan line, action spread...(anything else?). What possible causes would
you look at on and upright or console?  Or perhaps this is completely normal
for a piano of this era (1934 Monarch), and yes she's a beauty.

My suspicion is somebody tried to make it work with the 1 3/4" blow and came
up with the solution of severely deep dip. The piano had lots of bobbling
hammers that I was able to over come by taking up the lost motion.

Again chances are I will never regulate this piano, I was just trying to
puzzle out what I would do to try and make it play better. Is 3/8ths dip
with 1 1/2" blow barking up the right tree?


Thanks for any and all replies

Steve Blasyak RPT
Orange County Chapter

Pura Vida
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