Touch weight Metrology Question

[Isaac OLEG]

Hello,

You had first class comments from David, covering the whole process in a few
words. On a G something piano, with a complain of heavy touch without
visible reason (?) begin to look at the spread as chances are the spread is
compressed. How is the action regulating ? (deep, hammer/string)?

The spread may be 112.5 mm I believe, but you could check it visually .

Then you can take the measurements to assess what goes on with the weight of
parts & weight ratio.

Regards

Isaac OLEG



> -----Message d'origine-----
> De : owner-pianotech@ptg.org [mailto:owner-pianotech@ptg.org]De la part
> de Farrell
> Envoyé : mercredi 15 mai 2002 04:40
> À : pianotech@ptg.org
> Objet : Touchweight Metrology Question
>
>
> I am taking my second stab at touchweight metrology analyses of
> an action (my first was half-hearted and incomplete). Yamaha G5,
> 1963, action in very good condition. Complaint: action heavy. It
> is indeed with DWs all over the 60 to 80 gram range (mostly
> around 65 grams). Some notes do have a lot of friction, but many
> measured notes only have 10, 11, 12 grams friction, so clearly
> there is a problem with either too much weight hanging out
> somewhere, or bad geometry. KR is 0.49, BWs are mostly around 50
> to 55 grams or so. I have not measured strike weights and wippen
> radius weights yet.
>
> I have yet to go through and complete the Stanwood data sheet
> (I'm about half way through). My question at this time is general
> in nature: Is there any specific area I should be targeting for
> analyses? I guess I just feel like I'm collecting this data and
> don't have a clue as to what I'm going to do with it. I'll
> re-read David's Journal articles also.
>
> Maybe too early yet to even be asking questions. Just wondering
> if anyone that is familiar with this process has any
> recommendations. Thanks.
>
> Terry Farrell
>
>