I've always ass-u-me d that using the new Steinway Action frames with broached hangers would guarantee ideal geometry. I recently replaced an L frame and checked the action spread. It was 110.0mm with genuine current NY Steinway parts. I had and older action frame with broached hangers. I put the same parts on that and the spread was 112.5mm. The distance between the wip and hammer hanger holes was 2mm wider on the older frame. I'll shim the wippen rail to widen the spread, then have the piano owner, named Sam, play it again.
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David Stanwood
Stanwood Piano Innovations Inc.
West Tisbury MA
508-693-1583
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