Shubert Upright Bridge

[pianoman]

----------
> From: Ted_Sambell@BanffCentre.AB.CA
> To: pianotech <pianotech@ptg.org>
> Subject: Re: Shubert Upright Bridge
> Date: Saturday, July 05, 1997 5:59 PM
> 
>                       RE>Shubert Upright Bridge                    7/5/97
> 
> 
> 
> Dear all: 
> 
> When I was teaching the Piano Tech. Program at George Brown College in
> Toronto, we had a very similar bridge  on a late 19th. century piano. The
> make was Hoerr Bros., apparantly two brothers who had worked at Mason &
> Risch. The piano was an all round disaster, the bridges being the worst.
> 
> The design was as follows: 
> 
> Two rods, five thirty-seconds of an inch in diameter ran along the top
and
> lower edges of the surface of the bridge. These were partially set into
> shallow grooves. The center of the bridge was hollowed about one eigth
in.
> along its length. A pressure bar over the strings bent the wire down
> between the two rods. While this certainly solved the downbearing
> problem,it was impossible to keep the strings spaced, as this depended
> entirely on the accuracy of the hitchpin layout. Otherwise there was
> nothing to stop the strings from drifting sideways during tuning. It is
> also obvious that each string of a unison differed in length, thus
creating
> varying inharmonicity and making for tuning problems once again.
> 
> The student working on this piano actually ended up making an entire new
> back, complete with soundboard and bridges. He did a truly remarkable job
> and the piano sounded very good, considering we were not piano makers.
> There were just too many problems to do otherwise, one being that a scale
> evaluation revealed that there were three octaves which exceeded the
> permissible breaking percentages. Entirely re-designed bridges to correct
> the string lengths were made.
> 
> Regards,  Ted_Sambell@banffcentre.ab.ca    
> 
> --------------------------------------
> Date: 6/25/97 11:02 PM
> To: Ted Sambell
> From: pianotech
> pianoman wrote:
> >=20
> > Today I tuned a pre-1895 Shubert upright.  Instead of having an upper
a=
> nd
> > lower bridge pin on the bridge, the middle of the bridge was hollowed
o=
> ut
> > with a pressure bar appliance was screwed down on top of the strings.
> 
> 
> 
> To James Grebe, Warren Fisher, et al:
> 
> Well, now, wait a just a moss (We don't grow cotton out here, but there
> is lots of fuzzy green stuff that I think is moss. Or something.) pickin
> minute here! Just what was really so wrong with that Shubert bridge
> system?=20
> 
> One function of the piano bridge is to provide an acoustical and
> physical termination for the vibrating (speaking) portion of the string.
> Another is to couple the energy from that vibrating string to the
> soundboard/rib assembly. Apparently, this arrangement did both. At least
> to some extent.
> 
> Down bearing, of course, is a whole other subject from string
> termination.=20
> 
> James, you didn=92t mention what condition the bridge termination system
> was in. Just that it looked odd. Apparently, the system is still
> working=97at least to some extant. After 102 years, that gives the system
> some credibility all by itself. I=92d really like to know more about it.
> 
> I have some questions.
> 1) What did the strings actually rest on? Wood? Some type of metal
> insert? Anything?
> 2) Did this system continue all the way down through the bass?
> 3) What condition was the system in? Had the bridge developed any cracks
> where the screws from the =93pressure bar=94 went into the wood?
> 4) Was the =93pressure bar=94 continuous through each section, or were
> individual bars used at each unison?
> 5) How much string deflection was there?
> 
> I=92ve been puzzling over alternatives to the conventional offset bridge
> pin arrangement for some time now and I=92d like to know more. It seems
t=
> o
> me that, after a couple of hundred years of development, some viable
> system other than the bridge pin arrangement currently popular should
> have evolved.
> 
> I realize you probably didn=92t spend a whole lot of time examining the
> piano, but anything you can remember will be appreciated. A few of the
> things Rube invented actually worked pretty well, you know.
> 
> Thanks,
> ddf
> Mr. Sambell,
What you described sounds exactly like the Shubert I worked on.  We have a
mutual friend (Ken Burton) whom I have met on this list and he has spoken
very highly of you and I am honored to talk to you.  As I said I couldn't
nosy in at the construction because of the client breathing down my back. 
Warrens comments about strings moving around I'm sure was a problem.  I
have been doing this work since 1962 and this is the first I have seen of
these.
James Grebe from St. Louis
pianoman@inlink.com> 
> 
> 
> 
> 
>