Restoration of a Steinway A for the Skinner family
17) 
18) 
19) 
17) You can see in this picture how the pores of the wood
have been filled. When using paste wood filler, once must go on a bit of faith since
it is difficult to actually see the filler in the pores since it blends in so well.
18) The sound board has had numerous dimensions measured out. Including,
height of the nose bolts and the height of the dowel stand offs. Index holes have
also been drilled through the board into the rim. These will help in duplicating
this board. All these measurements have been marked right on the board.
19) A close up of some of these measurements. You can also see, in this photo
that the dowel stand offs have been drilled out. One has to be careful to remove as
much of the dowel as possible without actually marring the rastin (the shelf which the
sound board is glued to) beneath.
20) 
21) 
22) 
20) The sound board has been removed and all the old wood
and glue has been painstakingly removed.
21) Sound boards which have "died" usually suffer from many poor glue
joints. This usually means that it will be impossible to get the board out
completely in one piece. After the board is removed, any pieces which broke off, are
very carefully reattached in order to make the duplication process easier.
Fortunately, none of the index marks were attached to any of the broken bits. With
the possibility of breakage in mind extra index holes are always drilled to ensure that
enough of them are attached to the main section to maintain accuracy in duplication.
22) The dowels which reinforce the joint between the bridges and the sound board are
drilled out carefully trying not to damage the bridges. Additional index holes are
drilled through the board into the bridges to ensure that the bridges get glued onto the
new board in exactly the right location.
23) 
24) 
25) 
23) The top of the old board showing that the bridges have
been removed. In order to get the bridges off the boards cleanly, it is necessary to
use very slow and skilled chiseling techniques.
24) The bridges have been removed and are displayed here. They were removed in
such a way that any bits of glue which did not release caused slivers of sound board to
adhere to the bottoms of the bridges rather than causing bits of bridge to adhere to the
sound board. Then all old sound board wood and glue is removed from the bottom of
the bridges in such a way that the original glue line in retained exactly and completely
undamaged.
25) Another picture of the rim, showing the dressed out rastin.
26) 
27) 
28) 
26) The original pin block is shown next to the new pin
block blank before the blank was fitted to the plate.
27) Here, the new pin block is being fitted to the plate. You can see from the
dark spots where the pin block is hitting the plate in a direct wood to metal contact.
28) Tiny voids are still left in the plate lip to pin block edge joint after the
block has been fitted to the plate. These voids can easily be ignored since the
contact is excellent anyway. But in order to bring this contact up to a complete
100%, a thin layer of epoxy is placed on the surface of the pin block and then the block
is placed against the plate and clamped into position. A thin plastic wrap barrier
is used to prevent the block from becoming glued to the plate. Once the epoxy sets
up, the result is a fit to the plate that is more perfect than can be accomplished any
other way. It is only a slight improvement over the well done wood to metal fit but
it makes me feel better to know that it isn't just excellent, it is perfect. Enough
clamping pressure is used when this is done to ensure that all the original points of
contact of wood to metal remain simply wood to metal as before with no epoxy. The
epoxy is simply squeezed into the tiny low spots.
29) 
30) 
31) 
29) After the block has been fitted to the plate, it is
marked and then the screw and tuning pin holes are drilled out. The tuning pins are
drilled at an angle to assist in resisting the tension of the strings while the screws are
drilled at a 90 degree angle.
30) Once the pin block has been drilled, the indexes that were made before the
original block was removed are used to mark where the block needs to be cut in order to
fit into the case exactly as the original did. Then the block is cut to size on the
table saw leaving the line behind. Then the block is dressed down to a perfectly
straight and true glue joint on the jointer.
31) The capo bar has now had all the string marks removed from it and has been
polished to a high gloss to assist in ease of tuning.
32) 
33) 
34) 
32) The rib stock for the new sound board is first jointed
and planed so that it is perfectly square. Then the ribs on the original sound board
are measured for width and those width measurements checked against the insets cut in the
rastin for the ribs to glue to. In the case of this piano, I found that the width of
the ribs was considerably smaller than the insets cut for them. Since the ribs on
the sound board were quite thin by any standard, I felt it a good idea to make them a few
thousandths wider than original so that they would fit in the rastin very tightly rather
than fitting sloppily like they did originally. Also, care is taken to make sure the
ends of the ribs are cut to the exact angle needed to fit perfectly into the rim and the
lengths of the ribs are exact to attain a perfect fit as well. The original board
was not treated with this much care as an examination of the original ribs shows.
33) Now the treble bridge is located over the new ribs, measuring in from various
index holes that were cut in the rastin to align the bridge as nearly as possible to where
it belongs. Then the location of the bridge is marked on each of the ribs. The
purpose for this is so that I can shape the ribs in such a way that the highest point of
each rib is as nearly directly under the treble bridge as possible. Even Steinway
doesn't go to this much care when making sound boards but, believe me, the extra time is
worth it in the finished piano.
34) Now the surface of the ribs which is going to glue to the "skin" of
the sound board have been shaped to an arc to physically establish crown into the sound
board. Most companies rely on warpage caused by drying the skin of the board and
then gluing the sound board up dried. Then, when the humidity rises in the board, it
warps; causing crown to develop in the board. In my opinion, this makes the board
less able to freely vibrate and it also is a prescription for future cracking.
35) 
36) 
37) 
35) Now the new ribs are clamped to the old board so that
the old board will bend into the crowned shape of the new rib. (crown which the old
board had when it was new but which is has since lost.) Then the profile of the old
rib is transferred onto the new rib.
36) The ribs are now done and ready to be glued to the skin of the board. You
can see that the shape of the old ribs has been transferred to the new ribs along with the
kerfs at each end. The rounding of the ribs to finish this shape duplication will be
done after the sound board has been glued up.
37) Rebushing the keys. This wasn't on the original schedule for this
restoration. However, the owner is coming out to the shop and helping me with
various things in exchange for doing some of the "niceties" which would be nice
for the piano but not absolutely critical. In this situation, the action was mostly
replaced and the key bushings were not too bad but these new ones are perfect.
38) 
39) 
40) 
38) Another picture of rebushing the keys.
39) This is a little out of order, but this is the jig in which the crown is cut
into the new ribs.
40) A drying tent made to dry the panels of the sound boards before they are fitted
to the piano. Many rebuilders have a dedicated room in which they do this but I've
always coveted the space such a room would take up so much that I've never made one.
The drying tent method works equally well and will "go away" when I don't
need it.
© Copyright 2010 {David Rodgers' Piano Rebuilding}. All Rights Reserved.