If you search "Steinway glocken" you will find that Del explained it admirably on the pianotech list in 1997.
I won't copy and paste it, since I got roasted for doing that once before, though you'd think quoting our own list archive would be acceptable.
The thread title is "How to adjust glocken in Steinway D". Other sizes have one, too, not just the D's.
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Susan Kline
Philomath, Oregon
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Original Message:
Sent: 01-29-2020 16:54
From: Sean Stafford
Subject: What is this? Steinway D Question
I was taking up lost motion on the shift pedal under this Steinway D and noticed the large cast iron (I think ..) support arm under the piano with a bolt running up to the plate.
I've never seen this before or possibly I've seen it but never paid attention to it.
Any idea what this is used for? My guess is it supports the plate in some way....
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Sean Stafford
Endicott NY
607-239-4643
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