[pianotech] Best way to change touch on Yamaha Grand

[David Ilvedson]

You lift each key and put a tiny dab of glue on the hammer side of the balance pin hole and set back down on the punching.  When done, go back and cut the punching across at the back of the balance rail hole.   Put the key back on and proceed until done...at least that seems like a good method...I haven't done it yet...

David Ilvedson, RPT
Pacifica, CA  94044

----- Original message ----------------------------------------
From: "William Truitt" <surfdog at metrocast.net>
To: pianotech at ptg.org
Received: 1/6/2010 5:49:48 PM
Subject: Re: [pianotech] Best way to change touch on Yamaha Grand


>Thanks Vladan, your explaination is clear now.

>Will

>-----Original Message-----
>From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf
>Of V T
>Sent: Wednesday, January 06, 2010 7:11 PM
>To: pianotech at ptg.org
>Subject: [pianotech] Best way to change touch on Yamaha Grand

>Hi Will,

>I think, the original idea was to put a punching down (around the pin) and
>spot glue one half of it to the balance rail. Then, you cut some of the
>unglued end off. For example, if you are trying to reduce the ratio, you
>would, put a spot of glue on the side of the balance rail that is facing
>towards the hammers. When the glue dries, you cut some portion of the
>unglued side of the punching off. This makes the key pivot on the edge where
>you cut. It's a little more complicated than that, because the pivot point
>is constantly shifting, but in essence, you are removing any possibility for
>the key to pivot on the edge that you just removed. I hope I explained this
>well.

>Nowadays, I think most people will glue a thin strip of wood along the
>entire row of pins. The distance between the edge of this strip and the
>balance rail pin determines how much you end up changing the ratio. It only
>takes a little to get a noticeable change. Then, you put your normal
>punchings over that. I don't have a photo handy, otherwise I would post it.

>Vladan

>============
>"Vladen, could you explain a bit more completely
>how you go about doing this?  I am having trouble visualizing your shim -
>fulcrum in terms of material used and its co-existence with balance rail
>punching and felts.  Thanks.

>Will Truitt"


>