[CAUT] Down Weight Too High With New Hammers

[Ed Sutton]

For information, see www.pitchlock.com

Lots of information on the Touchrail.

es
----- Original Message ----- 
From: "Ed Sutton" <ed440 at mindspring.com>
To: <caut at ptg.org>
Sent: Tuesday, August 24, 2010 7:16 AM
Subject: Re: [CAUT] Down Weight Too High With New Hammers


> Paul-
>
> Fred has given the intermediate logic I was too tired to work through last 
> night.
> Another option would be Scott Jones' TouchRail installation.
>
> Ed
>
> ----- Original Message ----- 
> From: "Paul Milesi, RPT" <paul at pmpiano.com>
> To: "PTG CAUT List" <caut at ptg.org>
> Sent: Tuesday, August 24, 2010 1:51 AM
> Subject: Re: [CAUT] Down Weight Too High With New Hammers
>
>
>> Thanks, Fred, for this reply.  Your first paragraph states quite clearly
>> what my intuition was telling me so far as the implications of DW and UP
>> insofar as it being more of a relative weight issue (keys/hammers) and
>> possibly small geometry changes that make old and new parts not quite
>> compatible.  I also recognized that rep springs are not in play prior to
>> let-off, which is why I stated in my first post that I didn't think that 
>> was
>> the source of the problem.  I feel a "heaviness" in my hands/fingers when 
>> I
>> touch the piano, and as a pianist I just know it's not right.  The
>> measurements of course bear this out.
>>
>> Having said that, I don't rule out friction, and as time permits over the
>> next few days I will re-examine critical interfaces using the very 
>> helpful
>> input others have offered here.
>>
>> I have also just located 2 NYI Steinway repetitions from the last set I 
>> put
>> on an M, and am anxious to take them to the school and compare them with 
>> the
>> older ones on the D, see what's up.  Installing them side-by-side might
>> yield some interesting comparisons, if everything else is equal.
>>
>> Thanks, everyone, for your input.  I'll keep you apprised in the days 
>> ahead.
>> I won't have a large block of time for this piano for at least a couple 
>> days
>> now, so there's time to mull things over, try a thing or two, etc.
>> -- 
>> Paul Milesi, RPT
>> Staff Piano Technician
>> Howard University Department of Music
>> Washington, DC
>>
>>
>>> From: Fred Sturm <fssturm at unm.edu>
>>> Reply-To: <caut at ptg.org>
>>> Date: Mon, 23 Aug 2010 21:22:19 -0600
>>> To: <caut at ptg.org>
>>> Subject: Re: [CAUT] Down Weight Too High With New Hammers
>>>
>>> On Aug 23, 2010, at 2:53 PM, Paul Milesi, RPT wrote:
>>>
>>>>  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.
>>>
>>>
>>> From what you have said, it appears to be a weight and geometry
>>> issue. Those high upweights indicate reasonably low friction. Key
>>> leading on the heavy side sounds typical and removes the option of
>>> adding lead (though I wouldn't rule it out entirely - not having seen
>>> what you have seen, anyway). Roger Jolly is probably right in saying
>>> that cleaning and lubing the rep springs and grubs will make it feel a
>>> little lighter, but I don't believe it will change downweight/upweight
>>> (they aren't engaged during the part of key travel that is measured
>>> for weight). The change in feel will occur at the end of the
>>> keystroke, and can be very noticeable if there was caked grease and
>>> crud in there.
>>> I don't understand how the old geometry wipp can cause a difference
>>> in weight/ratio compared to the new one, but experience seems to say
>>> it can. After all, the capstans are touching the wipp heels at the
>>> same point, and the jack/rep lever is contacting the knuckle at the
>>> same point, whether it is new style or old. I guess it must have to do
>>> with the angle at which the jack addresses the knuckle, as that
>>> certainly does change (enough to require different thickness let off
>>> buttons). It wouldn't seem that changing one factor - the knuckle
>>> distance - would make that much difference, but it seems that it does.
>>> The newer wipp has very subtle differences in things like jack
>>> profile. This thread makes me curious to look very closely at just
>>> what those differences actually are.
>>> In any case, as a practical matter, the easiest thing to address
>>> might be weight. Reduce each hammer 1 gram, and you are in a better
>>> ballpark. Not a walk in the park, but doable (or close - 1 gram is
>>> about the max you can comfortably remove from a hammer by re-arcing
>>> and tapering). It does require removing and replacing all the hammers
>>> and shanks (and re-aligning), and a bench disc sander at a minimum,
>>> with Spurlock's tail arcing device or equivalent. Tapering can be done
>>> fairly evenly by timing and feel (how long and hard you hold the
>>> hammer against the sanding disc, balancing from one side of the hammer
>>> to the other). A scale to weigh before and after. You will need to
>>> taper into the felt area (not all the way to the crown) to get enough
>>> weight reduction.
>>> If it weren't a Steinway, I'd look at a quick geometry change using
>>> split balance punchings. But it is a Steinway, so no soap. At least
>>> not that I know of. Maybe Ed Sutton's idea about shimming the wipp
>>> would work. Worth the experiment.
>>> Regards,
>>> Fred Sturm
>>> University of New Mexico
>>> fssturm at unm.edu
>>>
>>>
>>>
>>>
>>>
>>>
>>
>>
>