The height of the keys from the keyed on these old Steinway uprights is almost always 2 1/2", measured from the bottom of the keytop.
The prime consideration here has nothing to do with the regulation. The action only cares whether the dip is correct. The only factor they cared about when setting the absolute height of the keys above the keyed was whether it would clear the key slip or not. (The keyslips are usually 1 3/4" high.) As a rule, most pianos will have the keys about 7 mm clearance above the key slip when the key is depressed.
As Yogi Berra once said, you can see a lot just by looking. The fact that the key height is measured usually from the bottom of the keytop tells you something about the rational behind their positioning. (Similarly, if you look at the scale numbering on pianos you will see it starts from the top and goes down, which tells you that the convention is to start stringing from the top.)
I've got a Steinway V from 1916 in the shop now. Let's use that as a for instance. The keyfronts measure 23.5 mm from top to bottom. Let's assume a 10 millimeter keydip. If you centered the dip at midway on the top of the key slip, that would be at about 12 mm from the bottom of the key front, which would give you also a distance of about 7mm clearance when the key was depressed. Again, you are using the key slip alone for a reference.
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Cecil Snyder
Torrance CA
310-542-7108
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Original Message:
Sent: 08-25-2017 05:23
From: William Truitt
Subject: Regulation specs for a 1915 Steinway I upright
Thank you very much, Clarence.
Will
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William Truitt
Bridgewater NH
603-744-2277
Original Message:
Sent: 08-24-2017 17:22
From: Clarence Zeches
Subject: Regulation specs for a 1915 Steinway I upright
Will: I must have hit the wrong key as everything disappeared. I'll start over. The Steinway I rebuilt was a 1916 upright. The key height was 2 1/2", the key dip about .410. Note 29 the first(lowest) string was tied as was lowest string on note 54. There was stringing braid all the way and felt strip glued to the plate all the way. The original TP's were .281 X 2 3/8.
The hammers: note 88 the rake was 83 degrees. Note 29 the rake was 85 degrees. Strike point on the bass was 2 1/2" and the treble was 2 9/16". Bass angle of the hammers was 108 degrees, tenor section note 28 angle was 85 degrees, note 38 was 86 degrees, note 45 was 87 degrees, note 48 was 88 degrees, note 50 was 89 degrees, and from 52 uo it was 90 degrees.
This was all the information I could find that I recorded before I dismantled the piano for the rebuild.
Clarence Zeches
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Clarence Zeches
Piano Service Enterprise School of Technology
Toccoa GA
706-886-4035
Original Message:
Sent: 08-23-2017 11:40
From: William Truitt
Subject: Regulation specs for a 1915 Steinway I upright
I have inherited a partially begun rebuild of a 1915 54" Steinway I upright piano. No regulation specs take from the original piano came with it, and the action is disassembled with all keyframe felts removed. The rebuilder has passed away, so I can't ask him. I don't have the Steinway Technical Manual. I have the old Randy Potter Piano Action Handbook, but it gives a 2 3/8" key height for verticals, but that seems a bit shallow, with a dip of 3/8" plus, doing some rough modeling with the old action parts.
If someone has the Steinway Technical perhaps they could provide me with the regulation specs (would they be the same as the Model K?
Thanks for any info you can provide.
Will Truitt
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William Truitt
Bridgewater NH
603-744-2277
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