Returning to the mystery of the repetition post bushing (friction drop): It occurs to me that manufacturers may have different protocols for treatment of hammer shankflanges versus all others.
Hammershank flanges are the most critical, and maybe the dipping/shrinking/sizing process is more rigorous for them, resulting in a denser bushing. Since the centers associated with the wippen take far less stress and are generally intended to have lower friction, maybe they are given a less rigorous initial prep, resulting in bushings that are less dense, so that when a larger pin, the friction drops more rapidly (the bushing cloth compresses).
Just idle speculation, but it would explain the anomaly.
Regards,
http://fredsturm.net
www.artoftuning.com"Education is not preparation for life; education is life itself." John Dewey
Original Message:
Sent: 8/14/2026 10:33:00 AM
From: Daniel DeBiasio
Subject: RE: Does a stronger repetition spring make the key return meaurably faster?
Good Morning David,
Thanks for mentioning my post on the other thread, but I disagree with the characterization that 2g (+/-1g) is unrefined. Different target gram specifications could be chosen but aren't. I think it would be worthwhile to explore why without dismissing this choice as a compromise.
The Steinway C&A pianos prepared for the concert stages use this pinning, and concert pianists perform with this pinning on a nightly basis. I understand this doesn't serve as proof of my point, but perhaps it serves as motivation to take Steinway's deliberate choice seriously.
Fred Sturm's background material posted above is very enlightening for understanding how different recommendations emerged and took hold.
This is a great discussion.
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Daniel DeBiasio
Technical Education & Support
ddebiasio@steinway.com
718-267-3229
Steinway & Sons
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Original Message:
Sent: 08-14-2026 09:59
From: David Skolnik
Subject: Does a stronger repetition spring make the key return meaurably faster?
Fred - Alan
There's been as yet no specific mention of manufacturers individual specific techniques or materials. What do we know about the cloth being used, or whether the same cloth is used for both (all) action pinning? Daniel DeBiasio provided Steinway's 'official' approach to pinning on the Pianotech version of this discussion. Manufacturers have mostly different criteria than 'boutique' rebuilds. They have to come up with something that will function within a range of extremes that are beyond their control. Those parameters have little to do with the refinements we're looking at here, even if most of us learned about this from Bill Garlick, while he was at Steinway.
I'm also still a bit curious about Kathy Smith's experience. It's not clear (to me) why the reduced friction at the rep lever would have created the noise she referenced.
Keep at it... we're not done yet. What would it take to publish the video?
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David Skolnik [RPT]
Hastings-on-Hudson NY
(917) 589-2625
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Original Message:
Sent: 08-13-2026 21:26
From: Alan Eder
Subject: Does a stronger repetition spring make the key return meaurably faster?
I saw the gizmo on his website a week or so ago. Don't know that is available just yet, but it sounds like they are going to make a batch now that their prototype is where they want it.
Yeah, I don't know why a repetition lever post would behave so differently compared to other center pin bushings, but I have certainly found that to be so, again, across brands (excluding WNG, of course).
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Alan Eder, RPT
Herb Alpert School of Music
California Institute of the Arts
Valencia, CA
661.904.6483
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Original Message:
Sent: 08-13-2026 21:08
From: Fred Sturm
Subject: Does a stronger repetition spring make the key return meaurably faster?
Very strange that a rep post bushing would be different. I see no design differences that would explain it.
Thanks for posting about Esmonde-White's bushing gizmo. I don't see it on his website. Is it available?
Regards,
Fred Sturm
"One's real life is so often the life that one does not lead" (Oscar Wilde)
Original Message:
Sent: 8/13/2026 6:06:00 PM
From: Alan Eder
Subject: RE: Does a stronger repetition spring make the key return meaurably faster?
Hi Fred,
You asked if pinning the repetition lever post is different from pinning hammer centers or wippen flange centers. Sadly, I would have to say yes. I have consistently noticed this, although I still do not know why it is.
Ever since you first publicized the protocol you just laid out for more stable pinning, that is what I have been doing myself. We do follow up on our own work and have found that hammer pinning, even in heavily used practice rooms, has become impressively stable, thanks to your method.
To that point, Oliver Esmonde-White has developed a tool he calls "Oliver's Bushing Burnisher." It consists of vertically disposed sample center pins, heated to a prescribed temperature, onto which both bushings of a given part are installed for a predetermined amount of time. The results are very consistent as well as being very stable.
Alan
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Alan Eder, RPT
Herb Alpert School of Music
California Institute of the Arts
Valencia, CA
661.904.6483
------------------------------
Original Message:
Sent: 08-13-2026 17:56
From: Fred Sturm
Subject: Does a stronger repetition spring make the key return meaurably faster?
Alan,
Is there any reason to suppose that pinning the repetition post is any different from any other bushing? Unless the spring is engaged, I can see none. Try the same thing with a hammer shank center, a wippen flange. See what the results are.
I know that I experienced considerable drop in hammer flange friction early on. I would do very meticulous work (I thought), pinning within a half swing and a gram of resistance. At some point, it occurred to me to check my work after a week or two. I found that my 4 gm/4.5 swings had turned to 2 gm, 7 swings or the like.
I examined my technique, and came up with what I now do. I only very rarely remove any material at all. The bushing is simply burnished rapidly with a smooth wire of the target diameter. If that burnishing fails to reach the spec, I use the next half size burnisher.
Heat caused by friction together with mechanical working of the fibers through the back and forth movement of the burnisher result in compression and tighter felting of the fibers. Much more stable.
So choose a size pin, maybe 1 to 1 1/2 sizes larger than the current pin, and burnish gradually going up by half sizes. At some point the burnishing will have maxed out. Insert a pin and feel how much resistance there is. When it feels right (pretty darned resistant), assemble the parts and check.
It is easier with shanks, as you can swing the shank on the burnisher, so you know where you are.
Original Message:
Sent: 8/13/2026 4:07:00 PM
From: Alan Eder
Subject: RE: Does a stronger repetition spring make the key return meaurably faster?
Hi Kathy,
I, too, I have experienced the overnight drop in repetition lever pinning friction, without the spring engaged, and across several different brands of wippens. Even posted about it, wondering why. (Too bad I don't eat insects, because all I got in a response was crickets!)
Alan
------------------------------
Alan Eder, RPT
Herb Alpert School of Music
California Institute of the Arts
Valencia, CA
661.904.6483
------------------------------
Original Message:
Sent: 08-13-2026 13:09
From: Kathy Smith
Subject: Does a stronger repetition spring make the key return meaurably faster?
I agree with what Fred said. I too had a lot of Steinways experiencing the "lockup" during those years. I also discovered during experimentation that if I just laid a piece of felt across the tops of all the sugarloaf cushions, the problem was solved. Smaller shims would be the semi-permanent solution.
Another note on this topic of repetition lever pinning. I pinned new reps to 7 or 8 grams for a while, on advice starting with Bill Garlick, and I'm happy to see the discussion here, with the factual details.
I discovered during those years that (for reasons I never understood) repetition pinning didn't stay where I measured it during the work. Notably, I was working on a fairly new Steinway D in Richard Carpenter's home, and as part of trying to solve a typical action noise problem, I pursued many ideas, including carefully re-pinning all the reps to 7-8 grams. (Carpenter had the D in a great room, and would play at 2am when the house was dead silent. And he was notorious, especially with his extensive car collection, for not tolerating any extraneous noises.) Richard Davenport came along a month or so later to help investigate the action noise, and we checked that same pinning. It was consistently down to 3 or 4 grams. After learning that, I started to re-pin rep lever sets in two stages. I would carefully install a pin at about 7-8 grams, but not cut off the pin, and leave the reps all lined up in the tray overnight. I learned that (Renner parts in those years) would drop about 5 grams overnight. If I pinned about 5 grams over my target, by morning it would hit pretty close and I'd cut off the pins, put the springs back in the grubs, and it would last. That finding remained true over about 20 sets, over about 5 years of time.
I never figured out why that happened so consistently. Did the felt heat up with the pin pushed in and cool off later? Did the felt compress a little bit overnight? I couldn't argue with the results. I haven't re-pinned whole sets in a while now, so I don't know if that's true of other manufacturers or current production. But it's worth doing a few samples before doing a whole set. I'd be very curious to know if anyone still finds that happening.
Kathy
Original Message:
Sent: 8/13/2026 12:48:00 PM
From: Fred Sturm
Subject: RE: Does a stronger repetition spring make the key return meaurably faster?
I'm going to offer some background material on this subject, specifically related to the high friction pinning of repetition levers and resultant higher tension springs.
A certain kind of Steinway repetition problem plagued me and many others during the 1980s and 90s. Eric Wolfley called it catastrophic action failure. This was apparently only a Steinway problem, not found in pianos of other makes. To put it most simply, on forceful repetition, a note would often jam up.
There was a lot of talk and study about the problem. Ken Sloane of Oberlin wrote a very detailed article about it in the Oct 1989 Journal (p 24) where he described trying to solve this issue in a (then) new model D. He tried everything in the book and eventually ended up adding length to the hammer tails, gluing on an extension and shaping it.
He noted, "As you may already suspect and as the alternative repairs in the previous paragraph indicate, the repetition problem originated from serious manufacturing error. The proper plate height/action height relationship was not built into the piano. I have measured other "D" pianos, one with a similar repetition problem and one without; and the problematic one has similar manufacturing defects."
Someone, maybe Eric Schandall, told me that the culprit for the repetition problem was that the shanks were too high off the cushions. And they were, consistently. In order to meet blow spec, they had to be. In order to lower them to the right distance above the cushions, blow would approach 50 mm and you would need to increase dip to over 11 mm. So I experimented with tacking on bits of felt on the tops of the cushions, maybe 3 - 4 mm thick. Problem solved.
(BTW, high speed videography shows that shanks often bounce off cushions during fast repetition, when the check doesn't engage the hammer - which is most of the time).
Later on, as I actually had a budget to replace parts and do major action rebuilds, I measured string height and shank center height on the various Steinway grands in my inventory in order to determine bore distance, and discovered that the root of the problem was exactly as Ken Sloane had surmised. The older Steinway grands (pre-1960) had string heights of 187 - 189 mm (as I recall. I'm pretty sure, but those notes have been misplaced). The newer pianos had string heights of 191 to as much as 195 mm.
Steinway hammer bore distance worked for a string height of 188 or so. If you used it for pianos with the higher string height, you would need to raise the shanks higher off the cushions, the tails would be too short to reach the checks, there would be overstrike, and so forth. Steinway hammers had too short a molding to use a longer bore distance, but using hammers from a different supplier and specifying the bore distance required solved all the problems.
When I was collaborating with Rick Baldassin, Jason Cassel and Scott Murphy on the high speed repetition videos connected to high friction repetition lever pinning, I asked Rick why he had come up with this protocol (I believe he is its original source). He said it was the result of training with Bill Garlick at Steinway. Garlick told him they needed to have extra strong rep springs to avoid catastrophic action failure.
Rick deduced that if there was high friction in the repetition lever center, there could be higher spring tension without causing other problems (double strikes and the like). He has been teaching and using this protocol for decades, and continues to be convinced that it is a good idea.
To put all this together, my take is that the high friction rep pinning protocol was a response to the bad Steinway geometry (lack of string height control in the factory) of a particular period - essentially a bandaid solution.The problem didn't show up in other brands of piano, with tighter manufacturing controls. So is high friction repetition pinning a good idea in general?
I'm skeptical. I think that, while it is well to be aware of rep lever pinning (it's better if it isn't 0 - 1 gm), excessively high rep spring tension can also lead to negative effects. For me, one of the key aspects of grand piano touch is spring resistance at the bottom of the keystroke. If the resistance is too high, it is very difficult to adapt finger technique to play with nuance, particularly at pianissimo. For this reason, I focus a lot on drop regulation, looking at it from the perspective of how much the spring will be compressed (resistance increases as the spring is compressed more). Starting with higher than needed spring resistance doesn't make sense to me.
Bottom line, my own approach is to have rep friction far less than 8 gm. I realize that the 8 gm standard is perhaps "the accepted norm" at this point, and that lots and lots of very authoritative people swear by it. I am presenting my own take, together with the detailed background that led me to it, in hopes that it may be help others think carefully and come to their own conclusions, rather than simply accept "what everybody does now" as gospel.
Regards,
Fred Sturm
"When I smell a flower, I don't think about how it was cultivated. I like to listen to music the same way." Mompou
Hi Alan,
Darrel Fandrich was a big believer in upweight as a very key factor, making sure it was at least 15 grams, preferably 20. He described this along the lines of "feeling the keys under the fingers."
In a situation with a pianist "the action not feeling very defined," I moved all the jacks farther under the knuckles by 1/2 turn. And that did the trick.
Bottom line is that the whole thing is a balancing act. We fuss over lots of details, some concentrating on one, some on others. But we never really know "THE ANSWER." Which is what makes our profession endlessly interesting.
The tag line under my signature is apropos: "Believe those who seek the truth; doubt those who find it." Gide
"Believe those who seek the truth; doubt those who find it." Gide
Original Message:
Sent: 8/12/2026 9:10:00 PM
From: Alan Eder
Subject: RE: Does a stronger repetition spring make the key return meaurably faster?
Fred,
Thank you pointing out the distinction to be made between quicker key return and faster repetition. Seems like the question I posed does not have a simple answer and, at this time, maybe not even a conclusive one.
And of course, swift repetition is one feature of a high-performing piano action, but it is not the entire story by a long shot. Nuance, control, reliability, and consistency all come in to play as well, as does the inextricable link between touch and tone.
Considering the player's perspective, there is the story of Joyce Meekins, RPT (and recent Golden Hammer Award winner!) when servicing a piano for Lang Lang. After the rehearsal, she inquired if everything was satisfactory with the piano. His reaction was positive, and he added that he would like to, "...feel the keys more under [his] fingers."
What did she do? Strengthen the repetition springs.
After the concert, she complimented his playing and asked if what she had done was a step in the right direction. He responded in the affirmative. Was he just being gracious? That is certainly a possibility, but it could well have been that the stronger springs gave him the feeling he was looking for, even though the repetition itself may not have been any faster.
It is so great that Scott Murphy has put high-speed video at the service of better understanding many of the things about which we have speculated but have not been able to either observe with the naked eye or measure, until now.
Alan
------------------------------
Alan Eder, RPT
Herb Alpert School of Music
California Institute of the Arts
Valencia, CA
661.904.6483
------------------------------