Seiler Job

[David Love]

Richard:

I saw all the data on your first post but it was in such a state that I
couldn't make it out.  Could you put it up again in a better column format?

David Love

----- Original Message -----
From: "Richard Brekne" <rbrekne@broadpark.no>
To: <pianotech@ptg.org>
Sent: September 06, 2001 3:23 PM
Subject: Re: Seiler Job


> Hi David, and thankyou for your input. Since both you and the others all
> recommend to deal with friction first, I certainly will start there. Other
then
> that you put your finger on something I didnt mention when posting the
samples
> data for this set. You mention a "normal whippen leverage". What I have
run into
> so far doing these is that WBW usually ends up around 9.0 to 9.5 grams.
(KR
> times WR). In this case I have a resulting average WBW wayyyy over that,
around
> 11 grams. KR is 5,2 -5,3 and I aggree that below that one starts running
into
> problems with dip/blow.....whippen travel distance really...
>
> I am not quite sure what the significance of this particular WBW average
is.
> Interestingly enough tho if I shoot for a Balance Weight of 40 then
everything
> works out fine by otherwise treating the system as a 38 BW, 9 WBW
specified
> system.... If you rewrite the equation of balance to solve for FW  you
have
> (R*SW) - BW + WBW on the other side of the equation. ( -40 + 11 is the
same as
> -38 + 9) Course I dont know if I can get away with this in practice... :)
Hav'nt
> come so far yet.
>
> Anyways whippen leverage is not what I am used to it being. I am not used
to
> looking at the knuckle radius or distance from center as it is not
directly a
> part of Stanwoods published Balance Equation. Tho when I get time and
money to
> get certified he no doubt will clue me in on how that fits into his
program. But
> I can certainly check those out and post them tommorrow.
>
> David Love wrote:
>
> > Richard:
> >
> > You need to look at the force leverage first.  What is the key ratio and
the
> > knuckle radius.  Those two will tell you a lot.  Assuming normal gluing
> > distance (130 mm), a knuckle radius of 17mm, and whippen leverage that
is
> > normal, the key ratio needs to be not greater than .55 to accommodate a
> > medium hammer weight without excessive lead. Less is better but it seems
> > that below .53 you can begin to run into problems with dip or blow.  I
would
> > try to resolve friction issues before you go any further.
> >
> > David Love
>
> --
> Richard Brekne
> RPT, N.P.T.F.
> Bergen, Norway
> mailto:rbrekne@broadpark.no
>
>