yamaha p-22

[Richard Brekne]

Dean May wrote:

> Sounds to me like Keith came up with a pretty ingenious solution. Although
> increasing blow distance by 3/8" is quite a bit. I suspect 1/8 to 3/16 would
> make a significant difference and wouldn't affect all the other adjustments
> as severely. I wouldn't think let-off or damper spoons would need changed at
> all. If you were decreasing blow distance you might need to adjust damper
> spoons, but not for increasing. Your primary adjustments will be lost motion
> and increasing key dip. The latter would be most easily accomplished by
> shimming the balance rail- probably 2 or 3 strips cut from card stock would
> do it.
> 
> Dean
> 

Well.. I played around with my upright action model today for a while... 
and found a 3/8 increase in blow caused quite a bit of problems... first 
off... The jack would no longer move far enough out, causeing 
bobbling... which left me right off with a choice of increaseing key dip 
to ll mm (pretty darn deep), or setting letoff to 4-5 mm away from the 
strings... big time loss of power there.

Damper timing was delayed a little, and the damper didnt pull away 
nearly as much.

In essence... In setting blow to 54 mm, I shortend the capstan close to 
  3 mm to get the jack to go under the knuckle. That means the whole top 
action gets lifted that much less.

I can see fudging perhaps 1/8  of an inch (a little over 3 mm) in blow.. 
but adding 3/8's...  hmmm... sounds like more trouble then gain off hand.

Cheers
RicB


> Dean May             cell 812.239.3359
> PianoRebuilders.com   812.235.5272
> Terre Haute IN  47802
> 
> 
> Hmm... perhaps I am reacting prematurly here... but on first reaction...
> you increased the blowdistance... a lot... :).. then lowered the
> capstans to let the jacks be able to return.... and nothing else ?? What
> happened to let off ? It would almost seem to me the jack tails wouldnt
> even reach the tender buttons with the capstans that low...
> 
> 
> 
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