Hi Parker, You're probably referring to WN&G's massive block of brass, which takes over the technician's judgement by feel. This will work for aftertouch. If not, a point needs to be made about the usual dip block we all knew before WNG's.
A dip block is a fixed dimension (regardless of the dimension we choose for it). Anyone who sets the keystroke not by dip, but by aftertouch, immediately notices that once the two determinants of aftertouch (blow and LO) are set at fixed amounts, the FR punchings used are different on every key. This remains true even if one were to put in a constant dip and then set aftertouch. Dip and aftertouch are two separate measurements. Aftertouch is directly related to the minute key-to-key variations on action ratio naturally occurring when you start measuring keystroke in increments under ~20mils.
There is no way to measure these variations in advance, and thus predict what each key's dip should be to deliver a specified aftertouch. All we can do is measure aftertouch directly and correct it there. (Anyone with experience in this can tell you it's far easier to do on the naturals than the sharps, but they all have to be done individually.)
Original Message:
Sent: 03-13-2024 09:29
From: Parker Leigh
Subject: Metric measurements
I can assure you that in the Bechstein and Bosendorfer factories that key height and key dip are set to metric specs. It is in final regulation that
aftertouch is set. Punches are roughly the same thicknesses as us. After touch is set on naturals using a dip block and then on sharps
by feel.
------------------------------
Parker Leigh RPT
Winchester VA
(540) 722-3865
Original Message:
Sent: 03-13-2024 08:15
From: John Parham
Subject: Metric measurements
I'm sure that in a factory setting, workers set parts to spec using metric quite often. We have less need for things like setting exact key height to a certain spec, though the technical exam does have metric equivalents for the regulation parts.
I'm still curious about dip. Most likely, no one uses units of measure more fine that 0.1mm. Perhaps most techs outside the U.S. refer to dip generically as shallow, medium, and deep?
Jp
Original Message:
Sent: 3/13/2024 1:08:00 AM
From: Blaine Hebert
Subject: RE: Metric measurements
I have been assuming that key height is determined by the fallboard. Dip is then taken off key height and everything else is regulated off of that.
------------------------------
Blaine Hebert RPT
Duarte CA
(626) 390-0512
Original Message:
Sent: 03-12-2024 02:18
From: Delwin Fandrich
Subject: Metric measurements
Does anyone actually measure the height of keys? I don't, and never have. One sets the height of the end keys and levels those in the middle by sight and by feel.
Nor do we actually measure the key travel. How can one, given that there is a soft landing and total key travel is a function of how much force one is using to depress it. Key travel is generally measured by touch, by feel.
To be sure different technicians have different methods of accomplishing both of these but I don't recall seeing anyone ever trying to set either of them using either the Imperial or the metric measuring system. Actual measures are a guide, sight and feel are the final arbiters.
ddf
------------------------------
[Delwin D] Fandrich] [RPT]
[Piano Design & Manufacturing Consultant]
[Fandrich Piano Co., Inc.]
[Olympia] [WA]
[360-515-0119]
Original Message:
Sent: 03-11-2024 09:39
From: Dave Conte
Subject: Metric measurements
This is becoming more and more important as we Americans sluggishly and begrudgingly migrate toward metric.
The one specification that .1mm = .04" will not suffice is key level. Humans can easily detect this thickness when
comparing adjacent items (such as piano natural keys). The Exploratorium in San Francisco (a hands-on science
museum) had an exhibit that specifically examined touch sensitivity and proved this hypothesis. How do people who
deal with a metric standard go about getting precise key level with a tolerance as large as .1mm/.04"? I can certainly feel and
see this much in adjacent natural keys. I know the answer is by a combination of thicknesses, and pose this only for consideration
and reflection.
DC
------------------------------
Dave Conte, RPT
Piano Technician in Residence
The University of Tennessee
College of Music
Knoxville TN
(817) 307-5656
Owner: Rocky Top Piano
Original Message:
Sent: 03-08-2024 18:53
From: Delwin Fandrich
Subject: Metric measurements
I've never seen dimensions carried to more than 1 point behind the decimal. Key dip might be specified at 10.1 or 10.2 (or whatever), but never 10.15.
In laying out a scale I've never used anything beyond a tenth of a millimeter.
Anecdotally, the best piano engineer I've ever worked with, Bob Ferris of Baldwin, used to tell me that, other than for things like wire, centerpins, etc., there was nothing in the piano that demanded more accuracy than the width of a pencil lead. The mechanical pencils we used were 0.5 mm in diameter.
ddf
Original Message:
Sent: 3/8/2024 4:35:00 PM
From: John Parham
Subject: RE: Metric measurements
Jahn Piano Supply sells metric punchings, including paper punchings 0.1mm and 0.2mm.
Potter's The Piano Action Handbook has all metric measurements for European pianos it looks like. The footnotes about aftertouch are in both metric and decimal.
On page 173 of Marios Ingress's Pianos Inside Out he mentions aftertouch values of 0.030" to 0.060" as 0.8 to 1.5mm. So far, I am not seeing more than 1 decimal place in metric readings... that seems to answer one of my questions.
I reached out to David Reed with Kawai. Next week he'll be at the Atlanta GA chapter meeting. Bill Davis will get more information from him about the mechanics of how the rest of the world sets and measures aftertouch.
Jp
Original Message:
Sent: 3/8/2024 11:51:00 AM
From: Jason Kanter
Subject: RE: Metric measurements
One way to approach this hasn't been mentioned: the thicknesses of the paper punchings in use in Metric lands. Surely someone can answer this. If they use our punchngs, then they must use thousandths of inches in aftertouch adjustments. What thicknesses are there in European paper?
------------------------------
| || ||| || ||| || ||| || ||| || ||| || ||| || |||
Jason Kanter
Lynnwood WA
(425) 830-1561
Original Message:
Sent: 03-08-2024 11:11
From: John Parham
Subject: Metric measurements
Thank you both for your feedback. The Piano Technicians Playground has an aftertouch station, and we use empirical to quantify different feels. It now has an opportunity travel across the big pond, and we're trying to modify it to fold neatly into the way the Europeans talk about, teach, and quantify after touch.
Thank you again for your input. It's invaluable.
Sent from my iPhone
Original Message:
Sent: 3/8/2024 9:31:00 AM
From: Alan Eder
Subject: RE: Metric measurements
I cannot speak to what native users of the metric do to express aftertouch in numbers. I use the metric system for virtually everything EXCEPT for string and center pin diameters (the sizes of which vary by .001"), and key pin sizes. In these areas, I find the increment of .001" more handy than .1 mm--which is a skosh less than .004" of an inch.
I agree with Parker that, at the end of the day, after touch is a matter of feel. For example, the setting of drop, to use a notion conjured by the late, great David Andersen, "sculpts" the perception of the moment of let-off, and therefore, the perception of after touch. And if a front rail bushing is a bit on the tight side, there seems to be less after touch. In both of these instances, the measured amount of aftertouch would be same, but the feel/perceived amount would be different.
Alan
------------------------------
Alan Eder, RPT
Herb Alpert School of Music
California Institute of the Arts
Valencia, CA
661.904.6483
Original Message:
Sent: 03-08-2024 07:58
From: John Parham
Subject: Metric measurements
Americans commonly use Imperial measurements for things like string diameters and aftertouch. Since the rest of the world seems to use the metric system, how do they measure and express aftertouch, only to 0.1mm?
When teaching aftertouch, I usually demonstrate the tactile difference between 0.30", 0.40", and .060". The metric conversion would make the range difference of only about 0.75mm. I suspect they have a different range they work with than we do because how the conversions work out.
How do European piano technicians measure and express grand aftertouch? What tools do they commonly use and what ranges do they work within?
------------------------------
John Parham, RPT
Hickory, NC
828-244-2487
john440@me.com
------------------------------