Northwest Theatre Organ History
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What Do Volcanos and Pipe Organs Have In Common?
Not much, but the May 18, 1980 eruption of Mount St. Helens in Oregon had Northwest pipe organ
From The Console magazine (V18, No. 7, July 1980, pp1-3)
ORGAN OWNERS IN VOLCANO REGION MAY HAVE TROUBLE
Written by Beverli Davis
With repeated eruptions of Mt. St. Helens and the possible threatening eruption of Mt. Hood, it's not
hard to wonder what both the short and long-range effects of the ash and sulfur dioxide will be on the
pipe organs of the affected area.
After seeing pictures of, and reading about the destruction and possible harmful effects, it dawned
on me that the pipe organs of the area could be adversely affected and that owners need to be aware
of the possible effects and to inspect their organs for signs of damage. It could be quite severe in
Ash particles are what is left of the underground molten magma after a violent eruption, such as that
of Mount St. Helens. Ash particles have the consistency of a gritty-fine-powder with sharp edges, much
like loose graphite; can stay suspended in the air to easily be sucked-in by an organ blower; and seem
to ease through even the tiniest of cracks to settle on everything, including the inside parts of a
pipe organ's mechanism to clog moving parts in close proximity such as tracker joints (when dry, a
light coating of ash may lubricate like graphite, but if it becomes heavy or damp, it will clog),
magnet armatures, pitman valves, and near spots where it could cause short circuits. This could mean
trouble and cause ciphers galore.
The best way to keep ash particles out of an organ is to keep the blower off, swell shutters closed,
and place filters and blankets over any blower and air conditioning intakes after an eruption until
the ash particles have settled out of the air. However, as particles settle they cling tenaciously
and it is difficult to vacuum them out of an organ's mechanism. Ash deposit, a day or even an hour
immediately after an eruption can probably coat the insides of blowers, regulators and windchests as
much as 30 or 40 years of soot from coal-burning furnaces.
Molten Magma contains gasses suspended in it which cause the volcanic explosion when they expand.
These combine with moisture in the air to form microscopic droplets which condense onto everything
and are absorbed into the skin, building surfaces, organ leather, etc. Sometimes these gasses are
inert, but most [are] corrosive such as salt, sulfuric acid, hydrogen chloride, or even arsenic.
When these droplets get into organ leather, felts or wood they could speed deterioration faster
and force replacement much sooner than under normal conditions.
Since the droplet-concentration level parallels the ash-concentration levels fairly closely, keeping
the blower off, swell shades closed and covering any air intakes should keeO [sp] most of the ash and
droplets out; but a little always manages to get into the action anyway. The best way to determine
what long-range effects will be is to periodically inspect interior surfaces, the action and
especially leather and felt for signs of ash-buildup, or deterioration. Prompt removal of such
residue will prolong the life of organ parts.