[CAUT] F..riction (rep spring)

David Skolnik davidskolnik at optonline.net
Thu Dec 2 18:17:07 MST 2010


David -
Hi.  Don't know if someone has already iterated the following:
The issue of 'somewhat' higher friction pinning of the rep lever is, 
as I have understood it, a way of increasing the speed and certainty 
of the jack return under the knuckle.  Apart from that,  I assume 
that, within some range, it's easier to regulate springs with 
moderate  friction than near zero.
The same weight hammer with a 16mm knuckle will have significantly 
more knuckle friction than at 17mm.  And then there's the 
leather.  There have been so many permutations of knuckle covering 
(or none) that display different sliding friction characteristics, 
both forward and return.  This has, I think, a lot to do with the 
difficulty of pianissimo.

David Skolnik

At 05:03 PM 12/2/2010, you wrote:
>  David Stanwood wrote:
>
>Hi Fred,
>
>I especially value your comments because you are also a serious pianist.
>The issue of the effect of strong rep springs on the quality of aftertouch
>and pianissimo control is relevant in respect to this conversation.  If
>the pinning of the rep lever is increased to allow the spring to work
>harder and more in it's range, we might see that we can more easily
>regulate the rep lever under the jack but there may be a negative effect
>on pianissimo control by the increase pressure that the pianists needs to
>overcome while engaging the drop screw at the end of the stroke.   I think
>I've been alluding to the possibility that a rep lever with very low friction
>can be regulated just fine IF the hammer weight and the spring dimension
>is well matched.
>
>Regards,
>
>David




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