[CAUT] Knuckle Direction

[Paul Milesi, RPT]

During the downstroke of the key, a lot of the weight of the hammer is on
the knuckle/jack, and there is a need to minimize friction between jack and
knuckle.  Trust me, a player can feel this friction, especially if
regulation isn¹t perfect, e.g., if the jack is a little too far back, so the
jack should move out from under the knuckle with the direction of the nap.
When the jack is returning to rest position, the weight of the hammer is on
the repetition lever, and any friction during return has no impact on touch.

As for the line on the Abel-type replacement knuckles, I can¹t remember
which direction it indicates, so I can¹t be of any help regarding that.

I seem to remember that this was discussed on the list sometime in the past
couple years and subsequently published in the Journal.  It¹ll be
interesting to see who weighs in this time around.  I, for one, wasn¹t on
the list at that time.
-- 
Paul Milesi
Registered Piano Technician (RPT)
Piano Technicians Guild
(202) 667-3136
(202) 246-3136 Cell
E-mail:  paul at pmpiano.com
Website:  http://www.pmpiano.com

Address:
3000 7th Street NE, Apt. 204
Washington, DC 20017-1402


> From: "Dempsey Jr., Paul E" <dempsey at marshall.edu>
> Reply-To: <caut at ptg.org>
> Date: Tue, 1 Jun 2010 15:57:57 -0400
> To: "pianotech at ptg.org" <pianotech at ptg.org>
> Cc: "caut at ptg.org" <caut at ptg.org>
> Conversation: Knuckle Direction
> Subject: [CAUT] Knuckle Direction
> 
> OK, maybe just too much week-end or perhaps old-timers....
> 
> I am re-knuckle-ing a set of grand shanks. The new parts are of Able
> manufacture and have a pencil line on each.
> 
> Does this line face the flange or the hammer?
> 
> I know the line indicates the direction of the nap of the leather, but which
> way is preferable.
> 
> 
> 
> Paul E. Dempsey, RPT
> Piano Technician Sr.
> Marshall University
> Huntington, WV
> 304-696-5418
> 304-617-1149
> 
>