Restoration of a Knabe Ampico Reproducing Upright for Carol Drummond
241) 
242) 
243) 
241) Now the whippens have been taken apart and are ready
for new components to be installed.
242) One batch of whippens after the restoration was complete. I am pinning
these a little tight in expectation that they will loosen up with the first hours of use.
They should loosen with the first days of playing to a point where they are just
right.
243) The design of the dampers on this piano is one in ten thousand. I
purchased new flange/spring assemblies to install onto these levers as well as new heads
with set screws. However, after a close inspection of the replacement parts which
are available, I had to conclude that the original design was so rugged and so enormous
that the new parts were dwarfed by the originals and, in fact, the replacements would not
work as well or be as reliable as the originals provided I did good reconditioning work to
them. Therefore, I spent an entire extra day's labor on these parts over what was
originally planned so that I could restore them to brand new condition. First, the
old damper felts had to be removed. These felts are very special and are not
available new for replacement from my suppliers. I will have to manufacture
replacement damper felts "in-house" in order to duplicate the original design.
244) 
245) 
246) 
244) The second step in restoring these dampers was to clean
and reinforce the springs so that they had tensions that equaled new parts. Then I
glass bead blasted the entire set to make them look new. Here, you see half the set
has been cleaned and the other half is yet to be done. This photo enables you to see
how new the restored dampers look. Since they are built so heavily, they will
operate and last just as long as supply house replacement dampers would have been expected
to. I simply had to put more work into them than was originally planned to make them
such.
245) The action rails and brackets that hold all the movable parts of the action is
now ready to be restored and cleaned.
246) The same assembly before it was restored.
247) 
248) 
249) 
247) Now all the rails have been removed. All the felt
that was in the least bit compromised, dirty, moth eaten or loosing its glue joint was
removed and replaced with new. The rails were cleaned and the springs were cleaned
and reinforced to bring them back to factory original specifications.
248) The action brackets after they were cleaned and refinished.
249) The action brackets contain bushings on which the hammer rest rail pivots when
the soft pedal is activated. These bushings were in good order but had to be removed
to clean the brackets; therefore, new bushings are being installed in this photo.
250) 
251) 
252) 
250) The hammer rest rail sits on the action brackets when
it is at rest. To set its location and silence its operation, hard felt pads are
glued to this rail. On this piano, these pads were very special. Rather than
just being made of standard scrap hammer felt, they were reinforced with a layer of felt
glued around the edges. This helped to keep the felt from settling and effecting the
hammer rail position and, therefore, the action regulation. I've never seen this
nicety in other upright pianos and it really isn't that necessary. However, to keep
original to the design and to provide the same added stability to the felt that the
original design had, I made new hammer rest bumpers modeled after the exact same design as
produced by Knabe. At the top, you see the old felts and, at the bottom, the
replacements.
251) The action rails and brackets are all restored and have now been reassembled.
252) In this photo, you can see the cleaned and polished damper lift rod with its
freshly lubricated flange bushings and the restored set of whippen/stickers. They
have all been reinstalled onto the action frame.
253) 
254) 
255) 
253) Here, we see another challenge that hit us as a result
of the American manufacturer suddenly closing his doors without warning. I was not
able to get an entire set of these very specially designed hammer butts all from one
maker. This piano has what we call a brass flange rail and the hammer butts are
brass flange rail butts. These type of butts are exceedingly good because they are
so durable and tough. However, they are very hard to install and regulate. In
addition, they are not the most common design of upright action part and, therefore, my
suppliers keep less of them around at any given time. Normally, getting new parts is
no problem but this time, I had to have them send me a mixed set with part of the set
having been American made and part being Japanese. The Japanese parts are actually a
little better because the spot on them where the hammer return spring rubs is lined with a
graphite impregnated felt punching as was used originally. In addition, the Japanese
provide the hinge pin with their part. The American parts must be hand pinned on
side and they have a lubricating paint in place of the felt punching. I find that
this paint does work but tends to make a little sound when the soft pedal is activated.
I, therefore, scrape that paint off and glue the appropriate felt punchings to the
part and impregnate that with graphite. The only difference in these parts, after I
finished the work of replacing the spring punchings and pinning them, was that different
colors of felt and leather were used by the different makers. The dimensions and
function of the parts will be exactly equal.
254) The hammer butts have now been installed onto the brass flange rail. If
you look closely, you can see this rail and how it keys into the hammer butts in this
photo.
255) The dampers have now been screwed back onto the action rails.
256) 
257) 
258) 
256) The hammer shanks have been individually sized and
fitted to their corresponding holes in the hammer butts. Before gluing them in
place, it is vital to make sure that they can be adjusted for an even spacing. The
standard style of hammer butt allows you to adjust the spacing of the hammers and shanks
by loosening the screw. With a brass flange rail, this is not possible. Any
inaccuracy in the spacing after the shanks and hammers are glued into place must be done
by heating the wood of the shanks to bend it. These have been spaced carefully and
then glued into place with hot hide glue. Hide glue is the authentic glue used in
this piano originally and leaves a color to the glue collar around the bass of the shank
that looks more authentic than modern glues. Hide glue holes exceedingly well and I
like the fact that it makes the action look authentic as well.
257) This is a photo of the ivory keyboard before restoration. Some pieces
were chipped and the rest were heavily yellowed. The camera doesn't show yellowed
ivory as badly as it really is. The process for restoration involves thoroughly
sanding the ivory with very fine sandpaper. Then the ivory is bleached with a custom
made two part wood bleach I make in house. It is important during the bleaching
process not to let the ivory remain wet for too long a period of time or it will raise the
grain of the ivory and ruin it. The next day, the ivory was still not white enough
and it showed no signs of grain raising so I sanded the set again and bleached them a
second time. On the third day, I decided that this set was not going to bleach any
whiter without damage to the ivory. So I gave the entire set one more good sanding
with fine paper and then buffed it to a high gloss.
258) This photo shows the restored ivory keyboard after four total days of sanding,
bleaching and polishing. I polished the brass capstan screws at the backs of the
keys after polishing the ivory as well.
259) 
260) 
261) 
259) Now is time to replace the backrail felt. On this
piano and most other uprights, the backrail felt is done in one strip which is usually
glued flat to the back of the keyframe. This method is not the best way. High
end brands of grand pianos usually use the method I am about to demonstrate which I
installed into this piano. First strips of felt are cut to fit the keybed from
material that is of the correct thickness for this particular set up. The white felt
will be glued solidly down and the green felt glued over it.
260) While waiting for the white felt glue to set up, I went through the job of removing
the leather covers that were on the rest posts for the action. Most upright pianos
have metal posts on which the action rests. This Knabe has leather covers added to
the system to ensure that the connection between the action brackets and the rest posts
can't make any sound. It's a nice little added feature that raises the overall
quality of the finished product another notch. The photo shows how the leather had
to be cut out and then is glued and strapped over the posts so that it is firm, secure and
permanent.
261) Now the underfelt strip is dry and I can proceed to glue the green felt over
it. The idea is to have the green felt glued along its edges but not where it
touches the white felt. This serves to make the rail quieter and also helps to keep
the felt from packing down and causing the keys to go out of regulation as quickly.
It's a lot of extra work to do it this way but the results are worth it.
262) 
263) 
264) 
262) The front section of felt was glued on and clamped into
place until the glue set. Now the other side is coated with glue and clamped down
until the glue sets as shown in this picture.
263) This photo shows a cross section of the finished glue up of backrail felt.
264) The entire keybed has been cleaned, polished and refelted. It is ready to
have the keys fitted to the keypins and the entire thing put back into the piano.
265) 
266) 
267) 
265) This photo shows the piano being restrung. Pads
and sheets are hung over the cabinet to keep the piano wire from scratching anything.
266) The finished restringing. All that remains to do as seen in this photo is
to run the stringing braid woven between the strings behind the bass bridge to prevent
those segments from producing unwanted noises. By the time this documentation was
done, that braid had been installed.
267) This is a photo of the piano's bottom board. I pulled it from storage to
clean and reattach it to the piano. Upon closure inspection, I determined that it
was no longer in good enough shape to be worth reusing. The glue joints that held it
together were all failing and the wood was in poor enough condition to make it unworthy of
being reglued. The decision was made to make an entirely new bottom board.
268) 
269) 
270) 
268) After the new board was cut from solid veneer plywood
that has exterior grade glue for better moisture resistance, The duplication process
begins. Here, I am transferring screw locations as well as places that must be cut
away or shaped in various ways to make it match the original. In a couple of places,
Knabe had simply gouged out some wood in places where they needed greater clearance.
I took the time to drill neat depressions in the wood in the necessary locations to
create a much more professional looking job than Knabe had done.
269) Here the new bottom board has had its shaping work completed and the new screw
holes drilled. Now it is coated with sealant to make it water proof. After the
sealant dries, the top of the board will be toned to match the color of the original board
and the bottom side will be painted flat black.
270) A side by side photo of the old board and the new one. You can see partly
why I discarded the old board in this photo from the fact that some of it is actually
falling off the main piece.
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