Kawai let-off (poor jack design?)

[Sy Zabrocki]

This topic talks about a Kawai KG-1 with two pedals. Was this a KG1-C, a
KG-2D
or just KG-1--or exactly what model? It might be helpful if we knew it's
age. Sounds like it might be at least 20 years old or more. Do we want to
make this broad statement about Kawai's jack design based this old "grey
market" model with two pedals.

Until recently I've been practially married to Kawai for many years and have
not seen this problem. Would the jack design on the KG-1 be any different
than on other KG models?

Next time I'm on a Kawai KG-1 I'll be checking this out.

Sy Zabrocki--RPT--Billings, MT

-----Original Message-----
From: Ron Overs <sec@overspianos.com.au>
To: pianotech@ptg.org <pianotech@ptg.org>
Date: Wednesday, May 05, 1999 1:59 AM
Subject: Re: Kawai let-off (poor jack design?)


>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
>