[pianotech] Interesting action on Yamaha YUA

[David Ilvedson]

The butts look like they have knuckles...seems like a very good idea...

David Ilvedson, RPT
Pacifica, CA  94044

----- Original message ----------------------------------------
From: "Ryan Sowers" <tunerryan at gmail.com>
To: pianotech at ptg.org
Received: 7/5/2009 2:59:18 PM
Subject: [pianotech] Interesting action on Yamaha YUA


>Hello all,

>A 1983 Yamaha YUA (52" upright) just arrived this past week. It is an
>intriguing piano. It has the radial bracing in the back, agraffs in the bass
>and tenor sections, and an action that I have not seen before. It lacks the
>traditional hammer return springs and instead has an unusual set of return
>springs attached to the player side of the damper stop rail. The springs are
>flat, about 1/8" wide and do not engage the hammer butt until the hammer is
>about 5/8ths or so from the strings.

>When the hammer is in check, the spring has very little pressure on the butt
>and the hammer is close to its balance point. The result is when the key is
>slowly released the hammer rises slightly out of check like you expect in a
>grand action. The repetition is very good, and it trills very nicely. It
>feels lighter, due to the fact that there is no hammer spring resistance at
>the beginning of the key stroke.

>Hopefully the picture will help this make sense.

>I'm wondering if anyone else has had any experience with this style of
>action?

>Ryan Sowers, RPT
>Puget Sound Chapter
>Olympia, WA
>www.pianova.net