action centers

[Isaac sur Noos]

Hello,

Renner spec. for the flange pin is more 2-3 g, that is may be why you
find these values. when they are exercised the action center will free
a tad, so it may be a good idea to move them back an forth a few time
before really using the gram jauge.

Best regards.

Isaac OLEG


> -----Message d'origine-----
> De : pianotech-bounces@ptg.org
> [mailto:pianotech-bounces@ptg.org]De la
> part de Phillip Ford
> Envoye : mercredi 14 janvier 2004 21:38
> A : pianotech@ptg.org
> Objet : Re: action centers
>
>
>
> At 12:18 PM 1/13/2004, you wrote:
> >i forget.  is it always a good idea to check resistance on
> all action
> >centers and re-pin, if necessary, even if all the parts
> are brand new?
> >as i've mentioned before, i'm working on a baldwin sd-10.
> >and another thing, this was my second hammer filing ever,
> and i seem to
> >have taken slightly too much felt off. so i have a slightly uneven
> >hammer line in the bass section.
> >
> >daniel carlton
>
> Daniel,
>
> I'd say that looks a lot better than the second hammer
> filing that I
> did.  Did you individually file the hammers?  With new
> hammers I generally
> tend to gang file the hammers (take a strip of sandpaper
> wide enough to
> sand about 4 - 6 hammers at once).  My intention is not
> really to take off
> a lot of felt but just to clean off the outside layer and
> to remove any
> cupping that came from cutting apart the hammers.  By the
> way, when you
> say an uneven hammer line, I assume you mean that the hammer tops
> would not form a straight line when the shanks form a
> straight line.  I would
> correct this in the regulation - make the hammer line
> straight, and let the shank
> line be a little uneven.  Probably not better technically
> speaking, but some
> people will take notice that the hammer line looks sloppy
> if you leave it that way.
>
> I think it's always a good idea to check every pin in the
> action, even on
> new parts.  How particular you want to be about it depends on your
> particular standards, the particular situation, and how
> much you're getting
> paid.  My experience lately with new parts is that the
> pinning is not very
> consistent and is often not what I consider acceptable for
> an exacting
> application.  Your mileage may vary.  If I was doing prep
> for a dealer,
> with what they generally pay, I would just check the pins
> in the action to
> make sure that they were not extremely loose or extremely
> tight - for
> example, lift up groups of hammers and let them drop to see
> if there are
> any excessively tight ones, and run my finger along the
> shanks at the
> hammer head end and see if there's any excessive free play
> - see if the
> jacks are free and return quickly, see if the whippens
> swing freely,
> etc.  If I saw any particular problem I would address those
> individual ones.
>
> If I'm getting paid lots of money to properly rebuild
> someone's piano, then
> I take an accurate gram gage (such as a Correx gage) and
> check the friction
> on every pin.  I want them to be consistent within some reasonable
> tolerance.  As an example, I'm currently putting new action
> parts on a
> Steinway.  I'm using new Renner parts (which as you
> probably know cost
> hundreds of dollars).  To take just one pin as an example -
> the wippen
> flange center - I want to see 5 grams on the gage when the
> flange starts
> moving when I put the gage arm next to the screw hole.
> I'll accept 4 - 6
> grams.  What I see from measuring the new parts out of the
> box is from a
> fraction of 1 gram (will barely move the gage) up to 10
> grams.  If I
> installed the parts on the action out of the box and
> checked them, the
> wippens would all appear to move freely.  However, there would be a
> significant variation in pin friction.  Pretty
> disappointing after spending
> hundreds of dollars, but seemingly a fact of life these days.
>
> Am I being too picky?  Perhaps.  If you look at that pin by
> itself, could
> the pianist feel a difference between a wippen flange
> friction of 1/2 gram
> and 10 grams?  Maybe, maybe not.  But if you take the sum
> of all the variations
> throughout the action that are not dealt with, then yes, a
> good pianist can
> feel the difference.  I go to a lot of trouble to smooth
> the hammer strike
> weights, properly align wippens to knuckles, finely
> regulate, etc., etc. to
> try and achieve an even touch from note to note.  Doing my
> best to make
> sure that pin friction is consistent just seems like part
> of that process
> to me.  Some sets of parts are better than others.  On some
> sets of parts,
> I've had to replace 3/4 of the pins to get the consistency
> that I want.
>
> Regards,
>
> Phil Ford
>
>
>
>
> Phillip Ford
> Piano Service and Restoration
> San Francisco, CA
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