June Journal and FW's

[David Love]

Richard:

That's why I wrote "in effect" you change the SBR.  You don't actually
change it, but the net effect is that you can maintain the consistent
relationship between SW and FW that you would otherwise only be able to
achieve with equal SBR's.  This is done by transferring some of the FW to
the assist spring.

David Love


----- Original Message -----
From: "Richard Brekne" <richard.brekne@grieg.uib.no>
To: "PTG" <pianotech@ptg.org>
Sent: June 02, 2002 1:48 AM
Subject: Re: June Journal and FW's


>
>
>  Bill Ballard wrote:
>
> >At 9:34 PM +0200 6/1/02, Richard Brekne wrote:
> >>>The wippen assist spring allows you to, in
> >>>effect, change the SBR from note to note by altering the wippen strike
> >>>weight.
> >>>
> >>
> >>????  dont follow you here Dave... The only way the ratio can really
> >>be changed
> >>is by changing the length of one or more of the levers. .... or what ?
> >
> >It's really a neat phenomenon. When you transfer the load balancing
> >from the FWs to the WAS (and remove the now "unemployed" leads), SBR
> >will seem to change, because all of a sudden the same SW can be
> >counter-balanced with less FW. It's an illusion of course.
>
> Ok.. I see that if you simply leave the numbers in the formula alone,,,
and
> just change FW to a lower value then you are going to change something
> else...... but to simply change the ratio ... ??.. actually  there is a
real
> change in the "weight" component of Whippen Radius.... which as I said
last
> would affect the WBW as a whole and could easily turn this into a negative
> number. But doing so wont change the Ratio...
>
> And besides... the Ratio isnt really changed anyways.
>
> Why do you say then that this is a neat,  (and illusionary) phenomenon ? I
> mean.. of course SW can be counter balanced with less FW... because you
have
> substituted for FW... not changed R.
>
> Scratching my head her a bit.
>
>
>
> >
> >More to the point it's a similar effect as increasing the stiffness
> >of the board by adding ribs. Instead of getting the extra stiffness
> >by thickening the panel, you get the same increase of stiffness,
> >without all the extra mass. Sort of like, if you wanted a NY Steinway
> >hammer to sound our favorite premium brick hot pressed hammer, how
> >much extra mass would you have to add. Well, if that mass was in the
> >form of reinforcers like lacquer resins or plastic, not much.
>
> Hmmm.... I dont know about this analogy...grin... sounds more like
confusing
> Water Buffaloes with Argentian Whitzie Flies to me. :)
>
> >
> >I think its kind of neat.
>
> Well... gee Bill... grin... I'll agree its neat anyways.. :)
>
>
> >
> >Bill Ballard RPT
> >NH Chapter, P.T.G.
> >
> >Visit Bhod Ankur, the underwater monument to yesterday's civilisation.
> >+++++++++++++++++++++
>
>
> Richard Brekne
> RPT NPTF
> Griegakadamiet UiB
>
>