1902 Conover upright jack lever

[Clark]

Hi,

Is the piece shaped like 7 or more like ]? The latter suggests a class
of actions with articulated jacks. Is there a hammer spring?

Staib Abendschein's Mastertouch upr. action vaguely is similar to a M&H
action I've seen (Jack Wyatt might know more about this one?),
presumably what Terry describes, though the high performance SA uses
articulated catchers sometimes with springs exceeding the strength of
wooden parts. Actually, as a rep. device there are precedents, many
older designs incorporate a stiff tab to the hammer butt besides a tape,
itself in turn which may perform a similar role for repetition (and
heck, moderately elastic felt on the inside of a catcher must do
something).

Examples that may be similar to x's Conover action:

Action in Gilbert's piano - U.S. 7441, 1850 (jack catch - screw button
in butt extension)
Upright piano actions, Koth - U.S. 179029, 1876 (screw button in b.ext.)
Piano forte action, Kranich & Bach, U.S. 233103 (spring)
Piano Action, Elliot & Spike - U.S. 244210, 1881 (screw button in
b.ext.)
Piano action, Letton - U.S. 290692, 1883 (aux. jack in b. guide slot)
Piano action, Ellis - U.S. 316023, 1885 (spring)
Piano action, Rogers - U.S. 326335, 1885 (spring)
...

These all let off by decoupling jack and knuckle physically, as opposed
to them articulated bebbes which kind of fold.


Ye olde tape is a great device to limit derangement of parts in removal
(wish brass rail Chickering grand actions had 'em like Wornum's), still
I wonder if its role has diminished over time.


Clark