Plate Bushings - was Re: Bushing vs. bigger pin?

[Farrell]

Jim wrote:

>"The sound board still has gracious plenty crown throughout the scale and
does not touch the outer rim anywhere."

Just a question regarding piano design/construction. I thought a soundboard
should idealy be fit snug to the outer rim.  Are not Steinways built like
that? How else can the "sound be reflected back into the soundboard" if the
soundboard is not snug against the outer rim? Do you think that in cases
where there is a gap between the soundboard edge and outer rim, the gad
should be filled? Just curious. I hear of this "sound reflected back" thing
and wonder if some of that may be just bunk. Thanks for any thoughts.

Terry Farrell
Piano Tuning & Service
Tampa, Florida
mfarrel2@tampabay.rr.com

----- Original Message -----
From: <JIMRPT@AOL.COM>
To: <pianotech@ptg.org>
Sent: Friday, June 02, 2000 8:04 AM
Subject: Re: Plate Bushings - was Re: Bushing vs. bigger pin?


>
> In a message dated 6/01/2000 8:57:06 PM, Ron wrote:
>
> <<"I know this happens
> altogether too frequently by accident, and with a low elastic recovery
high
> density block, it's a disaster, but with a 5 ply quarter sawn maple
block?">>
>
> Ron;
>  Perhaps you have discovered yet another "unadvertised feature" of the
> "Hex-a-Grip" pinblock...........something like... 'Why our pinblock is soo
> good it allows the pin to rest on the plate thus assuring no untoward
> pinblock hole elongation!!' :-)
>
>  I have just started on the partial rebuild of an Old Knabe grand. The pin
> block is made up of 4 layers of quarter sawn maple which are layered, from
> the top:
> thick-thin-thick-thin. In contrast a "Hex-a-Grip" is layered, from the
top,
> thin-thick-thin-thick-thin. This thingee has plate bushings in it and was
> still tunable although the pin torque was highly erratic..........when I
got
> the pinblock out I could see that NONE of the laminations were still glued
> together except for a very few spots. actually just enough to tell it was
supp
> osed to be a pin block. :-)
>
>   It is/was a "floating" block and the crushing of the bushings was  what
I
> would describe as "normal" with just slight forward crushing evident. I
> wonder if the first thick and first thin layers were enough to hold
"tunable
> torque"? Or if possibly some 'shearing' effect was responsible?
>
>  BTW this thingee is built like a truck! It has both rims made of
laminated
> Oak with the inner rim containing six 1/4" laminations and the outer rim
four
> 1/4" laminations. (how'd they bend this sucker? with steam?)  It only has
two
> belly braces but they are HUGE! The sound board still has gracious plenty
> crown throughout the scale and does not touch the outer rim anywhere.
>
>   As for the Research Grant minus the "suits" and "paperwork"....sorry Ron
it
> ain't gonna happen. However perhaps you could pad the Grant application
> enough to be able to add an AMS-P to the faculty. :-)
> Jim Bryant (FL)
>