compression vs rib crowning

[Marcel Carey]

André has a caul for rib shaping. I don't know the exact radius
though. He also has a gluing caul with an unknown radius and he uses
go bars for ribbing. The recent set of pre-crown ribs I got from him
were about 70 radius (from the not too precise measuring I could do).
I know for a fact that he has set humidity and temperature settings
that he CONSISTENTLY uses for the ribbing process. So I think that
most of the boards he duplicates might have the same crown. But then I
haven't ordered or seen enough to be 100% positive.

Marcel Carey, RPT
Sherbrooke, QC

> -----Original Message-----
> From: pianotech-bounces@ptg.org [mailto:pianotech-bounces@ptg.org]On
> Behalf Of Farrell
> Sent: 10 mars, 2003 23:32
> To: Pianotech
> Subject: Re: compression vs rib crowning
>
>
> So are you saying that Andre builds his boards just like
> Steinway? And what does he do when he gets an order for an
> 1892 Knabe soundboard, or an A. B. Chase, or a Chickering,
> a Mason & Hamlin, a Decker Bros., etc. Does everyone make
> soundboards exactly the same? How does he know what the
> radius cut into each rib was originally? Or the MC at the
> time of rib/panel glue-up? I'm not picking on Andre, but
> anyone that "duplicates" old soundboards. I say you can't
> do it unless you know exactly what the radius of each rib
> was, the radius of any mold used during rib/panel glue-up,
> and the MC of the panel at rib/panel glue-up. Perhaps for
> Steinway, one can duplicate a board as this stuff I think
> is known. But I really don't think any of that is known
> about piano companies that went out of business 100 years ago.
>
> So. How does Andre Bolduc or anyone else "duplicate" those
> boards? I say that they redesign them while keeping the
> appearance of the originals.
>
> Terry Farrell
>
> ----- Original Message -----
> From: "Don" <pianotuna@accesscomm.ca>
> To: <davidlovepianos@earthlink.net>; "Pianotech" <pianotech@ptg.org>
> Sent: Monday, March 10, 2003 10:15 PM
> Subject: Re: compression vs rib crowning
>
>
> > Hi David,
> >
> > I can't speak for most of them--but Andre Bolduc feels
> very strongly that a
> > duplicate board is *just that*. If you wish to redesign
> and send him
> > "specs" I'm sure he would be pleased to make a rib
> crowned board for
> > you--or if the piano had such a board in the first place
> he would "dupe" it.
> >
> > At 05:14 PM 3/10/2003 -0800, you wrote:
> > >Why is it that those who make soundboards (duplicate
> readymades for
> > >installation) don't make rib crowned boards?  Or do
> they?  The ones I know
> > >of seem to only make compression boards.
> > >
> > >David Love
> > >davidlovepianos@earthlink.net
> > >
> > >
> > >> [Original Message]
> > >> From: Ron Nossaman <RNossaman@cox.net>
> > >> To: Pianotech <pianotech@ptg.org>;
> <davidlovepianos@earthlink.net>
> > >> Date: 3/10/2003 4:54:11 PM
> > >> Subject: Re: compression vs rib crowning
> > >>
> > >>
> > >> >Is the difference between rib and compression
> crowning one of tone or
> > >> >longevity (or both).
> > >> >
> > >> >David Love
> > >>
> > >> Longevity, predictability, control. All in favor of
> rib crowning.
> > >>
> > >> Ron N
> > >
> > >
> > >
> > >_______________________________________________
> > >pianotech list info:
> https://www.moypiano.com/resources/#archives
> > >
> > >
> >
> > Regards,
> > Don Rose, B.Mus., A.M.U.S., A.MUS., R.M.T., R.P.T.
> >
> > mailto:pianotuna@accesscomm.ca
> > http://us.geocities.com/drpt1948/
> >
> > 3004 Grant Rd.
> > REGINA, SK
> > S4S 5G7
> > 306-352-3620 or 1-888-29t-uner
> > _______________________________________________
> > pianotech list info: https://www.moypiano.com/resources/#archives
> _______________________________________________
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>