Two action questions

Richard Brekne richardb@c2i.net
Wed, 01 Sep 1999 09:15:06 +0200



"Jim Coleman, Sr." wrote:

> Hi Richard:
>
> On your question #1, when the hammer is at rest, does the knuckle moulding
> point down the back side of the jack or is it at a slight angle to the
> jack? This can make a big difference.
>

Typically when I encounter this problem, the line of the jack compared to the
line of the knuckle core are at an angle of between say... 3 to 8 degrees
(guessing here). Its really easy to notice. The "point" of the angle made by
these points inwards, towards the back of the whippen. I rarely see the opposite
direction in any piano, but it happens. This is what makes me suspect the action
geometry. Changing the hammer to string distance affects this angle a bit... but
the distance is correct for the piano, and in anycase I wouldnt be able to gain
enough to straighten the line anyways. I am tempted to pull the whippen rail
backwards, but its already back as far as the screwholes will allow. Could
always enlargen the holes but.... well I thought I'd confer, compound, and
cohort a bit first.  grin

>
> On your question #2, it looks like the back rail is not bedded properly. You
> can test this with a long narrow screwdriver blade placed down between
> strings and touching the backrail cloth between two keys. Tap the
> screwdriver and listen for a knock between the keyframe and the keybed. Even
> though you may have bedded the keyframe properly at first, tightening the
> action bracket screws to the keyframe can sometimes screw this up.
>

Thats the funny thing tho,,.. the backrail is bedded, infact the bedding as a
whole couldnt possibly be better, and it doesnt really "feel" like its a bedding
problem. (tho the "feel" can easily be misleading to be sure) What do you think
to this "springy rail syndrom" suggested by others ??

>
> Jim Coleman, Sr.
>

Richard Brekne
I.C.P.T.G.  N.P.T.F.
Bergen, Norway





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