[CAUT] Down Weight Too High With New Hammers

[Paul Milesi, RPT]

This is an interim report on the thread I started back on August 23rd
(below).

Thank you to everyone who contributed; truly appreciated.  Your comments
encouraged me to read and study various materials concerning touchweight and
action geometry, and my understanding has gone to another level.

I learned at least in a primitive way to perform some touchweight analysis
by measuring DW and UW, then calculating Friction and BW.  Interestng!  I've
analyzed every note of a well-working Bluthner action, and learned a ton!

Now, back to the Steinway.  I am starting to conclude that the problem is
stemming from the capstan-to-wippen heel cushion relationship.  (Remember,
original repetitions 40 yrs old with new H/S/F.)  After re-checking key
friction, hammer flange pinning, etc., I changed out a couple original reps
for new ones from another job.  Here are the results:

Note            DW  UW  F   BW
F69-orig rep    69  33  36  102
F69-new rep     57  33  24   90

Careful study and comparison of the repetitions shows that the new cushions
are about 1mm proximal compared to the originals.  Also, the originals are
rather indented, since this piano had 40 years of gospel music played on it
in our Chapel.  When depressing keys very slowly, I had noticed I was
feeling a resistance, then a sense of giving-way and easier movement.  This
varies from key-to-key.  I now believe it's the variations in condition of
heel cushions.  Am I on to something here?

I have asked our chairman again for the dollars to buy a new set of reps
(these are teflon-bushed anyway, and I'd love to get rid of them -- flange
pinning is very loose on some -- and the original hammer flanges were
incredibly loose).  BUT...if he says no, how can I recondition these heels?
Should I undertake to replace felt and underfelt?  Never done this before.
Not sure that bolstering will yield a consistent, recital-level result?

Thanks for your thoughts.
-- 
Paul Milesi, RPT
Staff Piano Technician
Howard University Department of Music
Washington, DC


> From: "Paul Milesi, RPT" <paul at pmpiano.com>
> Reply-To: <caut at ptg.org>
> Date: Mon, 23 Aug 2010 16:53:30 -0400
> To: PTG CAUT List <caut at ptg.org>
> Conversation: Down Weight Too High With New Hammers
> 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
> 
> 
>