seminar reportreply

[James Grebe]

Hi Susan,    The discussion was about a slide he had of a Petrof action and
the problems he said they were having in the factory.  The hammer was
overcentereing  due to the fact that the action stack was sitting too low on
the key frame.  The action received thicker shoes under the action brackets
and the capstan position and size was changed and the problems left.  He did
not talk about the other problems that this problem caused, like tonally.
His main thrust was in the relationship of the action centers to one
another.
James Grebe
R.P.T. of the P.T.G
pianoman@inlink.com
Creator of Handsome Hardwood Caster Cups and Practical Piano Peripherals in
St. Louis, MO
-----Original Message-----
From: Susan Kline <skline@proaxis.com>
To: pianotech@ptg.org <pianotech@ptg.org>
Date: Sunday, November 15, 1998 11:36 AM
Subject: Re: seminar report


>At 09:38 AM 11/15/98 -0600, James Grebe wrote:
>[Alan Vincent:]
>>He also showed the effects of the hammer over and under centering when
>>striking the strings and what can be done about it.
>
>Could you tell us what he said the effects were?
>
>Thanks.
>
>Susan
>
>Susan Kline
>P.O. Box 1651
>Philomath, OR 97370
>skline@proaxis.com
>
>