broken plate

[Delwin D Fandrich]

----- Original Message -----
From: "Christopher D. Purdy" <purdy@oak.cats.ohiou.edu>
To: <pianotech@ptg.org>
Sent: September 07, 2000 1:03 PM
Subject: Re: broken plate


> A few people mentioned that Steinway has plates for these pianos.  I told
> Paul to call them today and get the story on that.  Would you recommend
> that Steinway and his Sons install it or is that something that any good
> rebuilder should be able to do?  I think he would not want to send it to
> the same rebuilder that did the last one.(!)  It is an older B, is it
> difficult to retrofit a new plate in an old piano?
>
> chris
>
----------------------------------------------------------------------

Chris,

Replacing a plate in any piano (assuming that the design is still in current
production) is not rocket science, but it is not all that easy either.  You
pretty much have to take the piano back to that stage of production.  That
is, you start over with the pinblock fit, bridge locations, etc.

Unless you were extremely lucky -- and it is highly unlikely that you would
be in this case -- the bridge pin locations would not align to the new plate
hitch pin locations.

So, you would start by removing the soundboard and starting over.  That
means you would have to accomplish roughly the following:
    -- plug the plate bolt mounting holes,
    -- fit a new soundboard and bridge set (but hold off on the bridge
height and pin locations until after the new plate has been located and
bolted down),
    -- fit a new pinblock first to the new plate and then to the rim,
    -- locate the new plate within the rim (and, in this case, you might
have to do some grinding on the plate to allow adequate clearance between
the plate flange and the rim) and bolt it down,
    -- establish a new plate height/bridge height relationship and plane the
bridges to height,
    -- lay out a new bridge pin pattern to match the new plate hitch pin
pattern,
    -- drill, notch and pin the bridge,
    -- string the piano and locate the strings through the upper two
sections,
    -- establish a working relationship between the hammers and strings
(this may involve radically spacing the hammers and/or the strings depending
on the variations that exist between the old and the new plate),
    -- possibly plugging and redrilling the damper guide rail to match the
new string placement,
    -- fitting the action within the action cavity for best hammer/string
alignment,
    -- possibly modifying the key end blocks to accommodate the new action
position,
    -- Etc.

It is quite likely that I have forgotten a step or two, but you get the
idea.  Piano rebuilders are used to duplicating and replacing the components
that have already been fitted at some point by a factory worker using a
variety of gages, jigs, fixtures and templates.  In this case the rebuilder
would have to work through the process in the same sequence as the original
factory worker, but without the benefit of those tools.

Yes, it is likely that several rebuilding shops in the country could do this
job as well as the Steinway factory, but it is unlikely that Steinway would
take that chance and sell them the requisite plate.

Regards,

Del
Delwin D Fandrich
Piano Designer & Builder
Hoquiam, Washington  USA
E.mail:  pianobuilders@olynet.com
Web Site:  http://pianobuilders.olynet.com/