Just for gits & shiggles I posted this question on FB. This was the answer.
It's a blow distance, let off (1/16"), and checking distance gage. The backcheck is just a handle.
Picture the common 5-in-1 gauge for grand regulation. This works similarly.
I'm guessing that the distance between the bottom (as assembled) of the backcheck and the bottom of the wire that's resting on the fall board is a typical or desired blow distance measurement.
Just slip the wire down through the strings; the backcheck will prevent it falling in to the piano, and will also act as a stop, so that the attached wire acts as a hammer height target.
Tipped sideways, it could work similarly to give a visual reference for checking height (I'm guessing width of the square bend is ~3/8").
And depending on the wire thickness, you could maybe also use it for setting letoff and/or drop.
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Maggie Jusiel, RPT
Athens, WV
(304)952-8615
mags@timandmaggie.net------------------------------
Original Message:
Sent: 11-26-2021 21:17
From: Martin Snow
Subject: What's it for
Hmm interesting. ...maybe
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Martin Snow
South Burlington VT
617-543-1030
Original Message:
Sent: 11-26-2021 20:07
From: Steven Rosenthal
Subject: What's it for
If it was clipped on the music rack, would it keep the page open?
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Steven Rosenthal
Honolulu HI
808-521-7129
Original Message:
Sent: 11-26-2021 19:10
From: Martin Snow
Subject: What's it for
Query
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Martin Snow
South Burlington VT
617-543-1030
Original Message:
Sent: 11-26-2021 18:53
From: Floyd Gadd
Subject: What's it for
Is this a quiz or a query? :-)
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Floyd Gadd
Regina SK
306-502-9103
Original Message:
Sent: 11-26-2021 17:56
From: Martin Snow
Subject: What's it for
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Martin Snow
South Burlington VT
617-543-1030
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