Kawai let-off (poor jack design?)

Richard Brekne richardb@c2i.net
Wed, 05 May 1999 13:07:38 +0200



Ron Overs wrote:

> Hi list,
>
> Frank Cahill wrote
>  I tuned a kawai KG-1 today. It's a gray market piano...two pedals.
> There was very little let-off and in some cases, no let-off.
>
> Frank,
>
> this symptom is not unusual for a Kawai KG action.
> The geometry (ie. built in friction) of the KG jack at the let-off button
> is one of the best examples of poor action design in the business.
>
> Try mounting a wippen on the workshop bench (hold it horizontally by
> clamping the wippen flange onto a support block), substituting the
> let-off button with a plain wooden dowel (also held horizontally).
> Examine the relative motion between the jack tender and the let-off
> button during escapement.
>
> And how does the KG let-off button cloth survive under real life service?
> It doesn't! As the jack tender gouges a groove in the felt  the let-off
> setting moves toward the string.
>
> Ron E. Overs
> Sydney, Australia
>
> Email: ron@overspianos.com.au
> Website: www.overspianos.com.au

Interesting tidbit.. Are there any neat fix proceedures for this ?

Richard Brekne



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