Anatomy of a WurliTzer Theatre Pipe Organ
Glockenspiel.
Next in line was the Glockenspiel. These simple looking 30 note actions break down, in about
25 hours, to around 2000 pieces. Each hammer pneumatic has eight thin wooden trim
strips around it held on with 20 escutcheon pins. Removing these without turning the
wood into splinters takes a lot of patience, care and time. Once they are off they are
very fiddly to sand and polish. Fortunately they are made of wood which does
polish up much better than most of the other woods in the instrument and only three coats
of shellac were required
to get an acceptable finish. Putting them all back again is another exercise in
patience.
The air hole in the bottom of the hammer pneumatics is slightly off-center. While I was
applying the new gaskets to them I had them all laid out in a row and it was quite
obvious one hole was out of line caused by one of the bottom sides being assembled
the wrong way around. It was clear that it had always been that way. This meant
that only one third of the hole would have lined up with the hole in the chest so I
suspect that for 70 years people have been wondering why one note of the Glock
was always weaker than the rest. To fix it would have required the complete
stripping down of the pneumatic again, drilling new holes for the hinge screws
and reassembling it all again with the likelihood that the screw holes to attach it
to the chest would also then be in the wrong place. I chose instead to carve a
channel into the base of the pneumatic to link the two holes together. This should
get the action much nearer normal than it has ever been before.
Another example where checking everything and not trusting that the factory built
everything perfectly paid off.
All the hammer pneumatics look the same, at first glance. They are not. The holes
For the screws holding the pneumatics to the chest are not all in the same place
so they do not necessarily line up if interchanged. The holes in the plate on the
end of the pneumatic, which holds the return spring, are also not all in the same place.
Trying to get them all back into alignment when they were not marked during the
dismantling required a lot of juggling. Numbering them would have been a good idea.
I sent the Glock bars to be chrome plated. This process did not appear to alter the
tuning much. I asked the metal finisher to remove as little metal as possible when he
cleaned them up before plating. I suspect he would have thought he could have made them
much prettier by rounding off all the corners and getting out every trace of pitting on the
surface but that would have been a disaster for the tuning.
Afterwards they were all still various amounts sharp so I was able
to gradually grind small amounts off the center of the back of each bar and get
them all to be much closer to being in tune than they were before. They are now
all within 0.3 cps of the correct pitch, which would be much better than they could
ever have been tuned originally.
The hammer springs and heads had become coated with a yellowish green oxide
so I cleaned them with steel wool, polished them with metal polish and then sprayed them
with lacquer to protect them.
Total time for the 30 note Glock was about 195 hours, but it looks great and with
the fresh rubber mountings for the bars it rings crisply instead of being a dull thud.
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