Recrowning

[Horace Greeley]

Richard and list,

AHA, there's the rub.

Even if you put in multiple wedges, the crown so induced has a net affect
only on the area of the board in the immediate vicnity of the bridge.
(Leonard, among others talked about this, I am not sure if he endorsed it.)


Also, "wedge" is a relative term.  In this case, it would be not so much a
wedge as a shim, driven into a saw kerf after the board is jacked up.  The
kerf, to be effective, would have to be made _prior_ to jacking up the
board, so as to be more open when the crown is "corrected", thus allowing a
larger wedge, which would, in turn, not only be more effectively clamped in
place, but would create more "staying power" in the induced crown.  The
placement of the kerfs should be determined during the taking of your very
painstaking measurements...

Like I said, just about as much trouble as installing a new board, without
the benefits.

Best.

Horace



>In reply, so as to keep the thread on Horace's comments, I seem to
>remember Leonard Jared talking about placing a wedge in the bridge
>ala keystone fashion. This would involve cutting the bridge in such a
>way to insert this as I don't think he mentioned removing the bridge.
> This is so vague in my memory, I am not sure of any other details.
>Perhaps some one else has heard of this.  The soundboard had to
>"jacked up" the incision made (before or after?) in a predetermined
>spot, the wedge inserted, and the sb let back down.  This was only
>from "hearsay" and  was it from him even??
>	Even if this is a case of me not distingushing dreams from reality,
>(is that why I perceive some saying, "Ah ha, he has let the cat out
>of the bag?") on THINKing about this, more than one wedge might be
>needed.  But where?  Also I would like to ask, how does the bridge
>run in relation to the crown?
>
>Richard Moody
>
>"I wanted only to try to live in accord with the promptings
>which came from my true self.
>Why was that so very difficult?"
>Hermann Hesse  Demian
>
>
>Ever seen a wine cork placed between the wooden post and a rib?
>Probably to stop a buzz. Not the one created by uncorking the wine
>bottle.   rm
>
>
>
>----------
>> From: Horace Greeley <hgreeley@leland.Stanford.EDU>
>> To: pianotech@byu.edu
>> Subject: Re: Recrowning
>> Date: Wednesday, May 28, 1997 8:08 PM
>>
>> Jon,
>>
>> Gee, I don't know, this is my fourth post to the list in one day...
>>
>> You wrote:
>>
>> >I heard from a guy who claimed he can re-establish sound
>> >board crown with shims. Even if it has 3/8" negative crown.
>> >
>> >Can someone fill me in on what I might have missed in the
>> >last few years of trying to keep up with the last few hundred
>> >years?
>>
>> Sure - this is something a bunch of us retired a long time ago.  It
>does
>> keep surfacing, however.
>>
>> So, now that you know what my prejudice is:
>>
>> While there are different methods, the deal is to disassemble the
>piano,
>> usually invert it, wedge the board up by driving wedges(!) between
>the
>> beams and ribs, then proceed with whatever repairs are in order for
>the
>> board (shimming, etc.), then glue all in place (except for the
>wedges, of
>> course).
>> Among the variations I've seen/tried
>snip   see thread




Horace Greeley			hgreeley@leland.stanford.edu

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