Two action questions

[Jon Page]

At 07:29 PM 08/31/1999 +0200, you wrote:
>Hi list
>
>I got two questions for you all relating to grand actions.
>
>#1.  From time to time I run into a so called quality grand sort (I wont
>mention the name but it starts with a "P"  grin) that has an odd ball
>problem regarding regulation. Basically said, unless the jack is
>regulated waaaayyy back, the note will miss. I ran into this problem on
>an action I just reworked, I had repacked the nuckles insureing a nice
>round shape, took much care to regulate the return springs nicely,
>height of the tip of the jack to repetition lever was set to play it
>safe (I have had this problem before on other such grands) made sure of
>basically everything.  Still, upon setting the action in the piano
>fifteen or twenty notes miss. And try as I may to find a reason, the
>only thing that seems to help is to set the jacks so that they are well
>back of the back edge of the core of the knuckle. Jack tips are barely
>beveled and this is taken into acount. I suspect action geometry..(It is
>never all that good on these things). Any ideas ???

Knuckles Too rounded(pointed?), pear-shaped is best
Top of jack angled too much?
Tight repetition lever pinning.
Weak jack spring (butterfly?) or sluggish center.
Heavy hammers.
Wear ridges on knuckles, sand smooth, brush, burnish.

>
>#2. Brand new Yamaha C7.  Action is very well bedded, and regulated.
>Still on hard play in the middle area, 8 or 9 hammers on each side of
>the note being hit raise (hop) very noticible. Feels like the hammer
>rail is moving. All screws are dead tight. Lots of power seems to
>dissapear. Only happens in the middle section of the action..
>Suggestions ??
>

Springy hammer flange rail, You should see what happens on and other well
know make (which begins and ends with an 'S'). 
Jon Page,  Harwich Port,  Cape Cod,  Mass.  mailto:jpage@capecod.net
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