Robbie, you mentioned a Seeburg mandolin attachment that used copper
cylinders suspended on stiff fabric. This is one I haven't seen. How
does it work? Do the copper cylinders have to drop below the hammers
every time or does it somehow come up from underneath?
Brian Smith
[ Like most of the mandolin attachments installed in vertical pianos,
[ the assembly is a long rod ("rail") of wood or metal located just
[ above the hammers. When the device is switched "on" (by a hand-
[ lever or a small pneumatic bellows) the rod drops so that the
[ dangling metal pieces are struck by the hammer (not a good idea!)
[ or are otherwise moved by the hammer.
[
[ The best designs minimize the added thickness between the hammer
[ and string, so that the jack can let off normally. Otherwise the
[ hammer and the action really get a beating!
[
[ In the Seeburg piano the total thickness of the two fabric supporting
[ strips which the hammer strikes is 0.030". Since it wrinkles
[ slightly it actually diminishes the hammer throw by about 0.050".
[ The letoff of the piano action has been adjusted accordingly. The
[ copper cylinder is attached by a loop of thin copper wire to the
[ loop of supporting fabric. Dangling below the hammer strike line,
[ it hits the strings only once, so the sound is not really like a
[ reiterating mandolin. (Maybe it should be called the "banjo
[ effect".) It's much like the common assembly with metal tabs,
[ except it's much heavier, and hence louder.
[
[ I'll photograph the Seeburg assembly and place a description at the
[ MMD Tech site, http://mmd.foxtail.com/Tech/ Send your photos, folks!
[
[ -- Robbie
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