Weighing Off the Grand Action - Part 10

Weighing Off the Grand Action - Part 10

Best Balance for Best Art

So now that I've taken you round the houses and bored or challenged you with numbers, let's return to practicalities and possibilities. Weighoff makes grand regulating more expensive but gives better results. How much better and at what cost for a particular piano will determine its value. What does the customer hope for and what will they expect of the results? Arguably, weighing off should be just part of the job, but if the job is already abridged for a budget or a timeframe, it will only be used as a when-necessary repair. But what if our customer wants to realize their piano's full potential? Weighoff fine-tunes friction, weight, and inertia, and these affect both playability and tone.

The action of an 1889 Steinway D recently came through my shop, another example of the practical importance of proportions, balance, and sensible choices. Everything in this piano, except for plate and body structure, had been replaced at some point. Somewhere in the early years of the Accelerated Action (pre-teflon), the keys, keyframe, topstack, and damper action were replaced. The belly, block, plate gilding, and strings were also replaced. And the legs, lyre, and music desk. A modernizing factory rebuild, I would guess. Later on, the keys were recovered and parts I never met were installed. Definitely not factory work. Hammer tails that chewed up backchecks. Too many punchings. One leg extremely loose from its replacement male leg plate being undersized and poorly installed. 

For this round, new parts of good quality were already selected, hung, and assembled when I received the action. The two main challenges I faced for regulating it were created by Steinway & Sons. The first was fitting an Accelerated Action into an action cavity not tall enough to receive it without its being modified. The modifications included trimming keys from over an inch tall, plus shoe, plus extended double button, down to 15/16", with no shoe and a simple, least-sized button. No shoe meant many keys were now back-chucking. Also, the new stack, keys, and keyframe (presumably from then-current production) did not quite match the original scale. Symptoms were an expanded treble cheek block, a pinching of soft-pedaling room, and bass and tenor shanks offset from their whippen cushions. Tilting hammers and/or their travel might have mitigated the latter except the strings were parallel to the keybed and clearly designed to receive hammers vertically. When the parts were made vertical, some shanks in the bass and tenor nearly missed their rest cushions but their hammers sounded beautiful.

The second main compromise stemmed from using shanks with a 17mm (instead of the 15.5mm) knuckle-to-center distance, a switch that Steinway New York undertook as a company in 1984 for the heavier hammers needed to tonally reach the back of bigger halls. But this concert grand had come to live in a private livingroom, so lighter hammers were appropriately chosen, and made effectively lighter by the new knuckle geometry. My complaint, really, was about the .430" key dip needed to make it work. This is right at the limit of acceptability for naturals and required raising sharp height to keep them above grade at full dip. If the whippens were being replaced, shifting their heels a millimeter back, coupled with also moving the capstans a millimeter back, could have restored a more normal key travel at the relatively desirable expense of making the very light hammers feel a little heavier.

The design of the Accelerated Action offered key leverage dynamically changing from lighter weight to longer hammer-rise during the down-stroke. Brilliant. And bringing the compensatory key weighting in closer to the balancerail reduced the overall inertial load. But the costs of converting from old to new are considerable.

The original whippens with their felt-adjusted jack positioning were long gone, and the replacement whippens brought with them their era's legacy of verdigris in the flange bushings. The new hammer tails at 1 inch long mismatched the originals that would have tapered from 1 1/16" in the bass to 7/8" in the high treble. This showed up in hammers catching at the very top of the bass backchecks and incrementally lower in the tenor and treble backchecks since the backchecks were still height-tapered in the opposite direction. 

The factory-replaced whippens featured rest cushions that were too short, made worse in the mid-range by a slight upward bowing of the plate. A hazard of leaving these unmodified would be rear hammer shoulders bumping on the tops of backchecks, particularly in the high bass and tenor.

The two main challenges, keys elevated for half-rounds and changed knuckle position, interfered with the relationships between backrail, balancerail, and frontrail. I had to significantly shim backrail cloth and reduce punchings under both balance and front rails to end up with adequate balance pin clearance above buttons and adequate front pin in front bushings. This situation was exacerbated by raising the sharps relative to naturals. And elevating keys at the back, of course, meant raising underlever and sostenuto tab heights and from them, trapwork, key upstop rail, and sostenuto rail elevations. All made extra work for the regulator. 


When enthusiasm for a piano rises in the concert pianist, it is a wonderful thing. Their spirit soars, their talents fully manifest, and the listener gets emotional.

What can stir such a response? Consistency note-to-note, a well-integrated tuning, and responsive repetition. They elicit confidence. And confidence taps all knowledge, feeling, and sensibility directly, without instruction from little voices in the head, without reference to who is listening or what they might think. Scales, memorization, and all forms of effort are transcended.

The Grandwork System assembles the steps that make this happen, puts them in a compelling order, and offers a plan to set this stage every time. Each piano has different fixed characteristics and each player comes with different preparation and repertory. But every piano and every player benefit from a fairly accessible list of details being in place.

Even friction, for instance, and the optimum degree of friction, in places of dynamic contact: action centers, key bushings and balance holes, capstan/whippen heel and jack/knuckle slide paths, keyframe/keybed, damper wires/guiderail bushings, damper felt/strings, lyre/trapwork, and more. Each of these has its place in the hierarchy of most-to-least importance, but each, if sufficiently off, can puncture the confidence bubble and interfere with music-making.

When hammer center friction is even and just right, coupled with even aftertouch and damper lift, incredibly soft playing becomes possible, extending color palate and dynamic range, extending musicality for both instrument and performer.

When the weighoff is fine-tuned, i.e., the action is carefully balanced, when the upweight, downweight, and inertia all taper helpfully from bass to treble, the player's body and the piano's connect as if one body and energy flows through this body without qualifying hesitations or demands for attention. The music can just sing.

When the vertically arrayed action parts actually work vertically, that simplicity enhances power and repetition. And when strings are mated with hammers that arrive vertically at strike, tone is enhanced with a clarity not achievable in any other way. And soft-pedaling can choose any spot for its desired shade of softening.

When both the athlete and the artist in the player can shine unobstructed, power surges as needed and can retreat to a most delicate touch.

We, as real-world piano technicians, often don't get to do all that it takes. Time is too short, budget too small. Too much noise, changing atmosphere, arbitrary strictures. Fine, we already live with these constraints. But given the time, the budget, and an expectation of best results, what do we do? Being well-prepared, with a repertoire of protocols and principles and the experience of applying them, helps. The better that preparation, the larger the repertoire, and the greater our experience, the better we can cherry-pick what will have the most impact and offer the best outcome.

Then, all can still be undermined by a ringing note, a buzz, a squeak, or a sour unison. That part of the technician's landscape is predictable and perennial. But with the best overall prep in hand, we know which things are in compliance and that helps us find and address a troublemaker.

This last outpouring comes out of exactly what happened. Work finished up Friday for the concert on Sunday. Sunday morning, A49 had a ring. All the dampers around it worked perfectly. I started by muting strings methodically up and down the piano to find a sympathetic source. No luck. Then I corrected every little deviance of this damper from its neighbors. Then I discovered moth damage in its rear pad. And so on. Eventually, I turned back to sympathetic ringing, in spite of no clear symptom. By plucking the damper-muted unison strings of likely suspects and fiddling with both strings and dampers, I did finally diminish the ring. Then, with no time left for further tweaks, I had to go. There was this darkness before the dawn. My customer had been anxious and I had set about doing what could be done. She was appreciative, but I drove away unsettled by this latest glimpse of the world of imperfections. 

Apparently, when the performer arrived, she immediately loved the piano. After her warmup, she said that she "wished to come every day to play it". This spontaneous enthusiasm launched her well above the blemishes, and my customer's husband said "it was the best concert he had ever heard". So the methodical march through what could be done had brought the artist such a friendly greeting that anxieties evaporated and a best performance emerged. The theories and principles had prevailed, sun shining, customer pleased. And weighoff, in my opinion, was the catalyst.

Next time, "New Parts for a Vintage Double B"

  • Part 1 "Why Weigh Off?" 
  • Part 2 "My Strategy" 
  • Part 3 "Method and Style"
  • Part 3a "Regulation Strategy Review" 
  • Part 4 "Pragmatics"
  • Part 5 "Trials and Errors"
  • Part 6 "Levers"
  • Part 7 "Playing with Proportions"
  • Part 8 "Weight, Friction, Inertia, and Distance"
  • Part 9 "Plan by Number?"

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