MOI moment of inertia. The accelerated action incorporated two changes: the roller bearing and the movement of the leads toward the balance rail. If you take sample up and downweights of, say, all the Cs (you can skip c88) and pictures of the lead pattern on those keys (if you can't measure the frontweight) it will help us to give a more informed opinion.
David Love
www.davidlovepianos.com
-----Original Message-----
From: "Paul Milesi, RPT" <paul at pmpiano.com>
Sender: caut-bounces at ptg.org
Date: Wed, 25 Aug 2010 02:45:54
To: PTG CAUT List<caut at ptg.org>
Reply-To: caut at ptg.org
Subject: Re: [CAUT] Down Weight Too High With New Hammers
David,
I appreciate your input. I confess I have to work to keep up with your
analysis, but I do understand your point of leads located closer to the
balance rail (³further back²) more likely to produce a better feeling action
than fewer leads up front. Isn¹t this the real principle underlying
Steinway¹s accelerated action?
What is MOI? Some type of inertia?
At this point, I can¹t wait to get back to this piano in the next day or so,
experiment with some things, take some better measurements, and even take
some pictures of the key leading, etc.
Again, thanks for your thoughts, which I hold in high regard.
--
Paul Milesi, RPT
Staff Piano Technician
Howard University Department of Music
Washington, DC
From: David Love <davidlovepianos at comcast.net>
Reply-To: <caut at ptg.org>
Date: Tue, 24 Aug 2010 15:27:50 -0700
To: <caut at ptg.org>
Subject: Re: [CAUT] Down Weight Too High With New Hammers
Just two comments FWIW. If the shanks cause the action to require a .415
key dip (meaning deep) likely the action ratio is low enough which it
doesn¹t sound like from the description. Moving key lead toward the front
in order to increase the front weight and lower the balance weight can be
counterproductive. The issue isn¹t the number of leads but the placement
and overall front weight. Packing the front of the key with lead even if
it¹s fewer can contribute to the MOI and create a heavier feeling action
than more leads with equal front weight closer to the balance rail. Given
the choice of 5 or even 6 leads closer to the balance rail versus 3 pushed
up close to the front of the key and equal front weights you will probably
be better off with more located farther back in terms of performance.
David Love
www.davidlovepianos.com
From: caut-bounces at ptg.org [mailto:caut-bounces at ptg.org] On Behalf Of Brent
Fischer
Sent: Tuesday, August 24, 2010 2:25 PM
To: caut at ptg.org
Subject: Re: [CAUT] Down Weight Too High With New Hammers
Paul,
Someone will feel this is a heavy action to play. Take your reps
off and replace the whippen heel felt. Use Pianotek's green action
cloth, medium thickness and that will solve that issue. Replace
the jack punchings to reduce noise and the rep lever punchings
also. Make sure the centers are in spec.
The shanks you are using may push a .415 keydip making
it "feel" heavy. If you are dealing with the accelerated action, there
was pre-leading done close to the balance rail. Take a bass and
mid-range key and re-move the three closest leads to the balance
rail. Move leads as close to the front as possible with a fifty-gram
weight on the front and see what you get, if the results along with
reducing molding weight as suggested on these trial keys gets
you there then pull the leads and re-weigh as close to the front
as possible, plug holes, I believe Pianotek sells the plugs. Make
the damper lift just a hair late and you may be home free young
man with 30 bucks of material.
Brent
--- On Tue, 8/24/10, Wigent, Donald E, Jr <WIGENTD at ecu.edu> wrote:
From: Wigent, Donald E, Jr <WIGENTD at ecu.edu>
Subject: Re: [CAUT] Down Weight Too High With New Hammers
To: "caut at ptg.org" <caut at ptg.org>
Date: Tuesday, August 24, 2010, 7:14 AM Hi Paul Don Wigent here. It is
possible to take wate off the hammers by taking wood from the inside of the
hammer tales, If there is some wood to remove. Remember 1 gram at the hammer
equals 5 at the key. If you should deside to remove some wood from the
inside of the hammer tale, use a small drumb sander on some sort of drill
pres or some thing. It can be dun by hand no jig needed.. Between the
removal of wood and proper regulation you will have less tw
Don Wigent
PS Don't get wigged out just do your job..
-----Original Message-----
From: caut-bounces at ptg.org [mailto:caut-bounces at ptg.org] On Behalf Of Paul
Milesi, RPT
Sent: Monday, August 23, 2010 4:54 PM
To: PTG CAUT List
Subject: [CAUT] Down Weight Too High With New Hammers
I installed pre-hung S&S hammers on the '70 S&S D, forced to use original
repetitions because of budget considerations. With the regulation only
"roughed in," the down weight feels too high to me when I play it. Now I
find it's measuring in the range of 55-60 grams throughout. I have
addressed friction in every area except removing and cleaning repetitions.
I can't believe rep spring grooves, etc., would make that much of a
difference; they don't seem that bad.
The new hammers are hung on NY improved shanks with knuckle further out.
I compared hammer/shank/flange #44 from the original and new sets, and
there
is, if I remember correctly, about a 2 gram difference. But the originals
are so beat, I don't know if it's a very meaningful comparison.
Would mixing original 1970 reps with NYI H/S/F cause the geometry to be
that
different? I was told by David Kirkland that I could "make it work,"
although using older repetitions wasn't first choice. I know the hammer
weight changed in 1984, but understood that using NYI shanks and flanges
would be all the compensation that was needed for the additional weight.
By the way, the upweight measures roughly 28-30g. Also a little high, no?
And it seems to me there's a lot of lead in the keys, but I'm definitely no
expert. Doesn't this imply a somewhat too-heavy hammer?
I don't mean to be taking any shortcuts here, but there are time
constraints
and a balance/compromise that must be struck with all the other instruments
I'm responsible for. This one is starting to drown me. Just wondering if
this touchweight issue is common when putting new hammers on a Steinway D
from this period, and if there is a typical or common remedy or approach to
solving the problem.
This is only my 3rd set of hammers, and my first set completely on my own.
I'm thinking of attending the PTG hammer hanging class with Mike Carraher
and Keith Bowman in October. Any thoughts on whether I'll learn skills in
addition to hanging (determining bore angle, etc. and boring hammers, I
assume?) that might help me fix this? Will they address how to arrive at
final touch weight? I want to learn! Guess I should contact Mike or
Keith.
OK, now I've exposed my near-total ignorance in this area and am
embarrassed. Thanks in advance for any suggestions.
--
Paul Milesi, RPT
Staff Piano Technician
Howard University Department of Music
Washington, DC
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