At the piano, an initial assessment of how the action fits and performs presents a hierarchy of needs to be discussed with the customer. A full regulation includes filing hammers, adjusting hammer and rep lever friction, weighing off, tuning, and voicing. Replacement parts or restoration of existing parts can easily be added to this process. Or a trimmed down version might be needed to fit budget or time constraints.
We might have to take the action out and apart to cleaning and solve excessive friction. But if not, after validating frontrail and backrail fit, we bed balancerail (with a WNG Bedding Tool), take bedding and strike samples, and setup on the bench - all without having disassembled the action. Remove the action return spring before doing these steps, as the spring adds friction and stiffness at either end, where the keyframe is already stiffest, and over time embeds itself in the keyframe, freezing the high treble elevation of the keyframe. If backrail or frontrail have problems, the action comes apart and we follow the long form bedding procedures of the Grandwork™ Bedding Protocol.
When the bedding validates, we take bedding and strike samples, using Keysteps for the bedding samples and a WNG Dip Tool for weighted kissing samples of strike (not dip samples) and head to the bench!
The first visit, then, could take just over an hour, with bedding and sampling accomplished and the next visit, with the now-regulated action in hand, may be a partial day’s work to fine-tune hammer spacing and mating, regulate dampers and pedals, tune, and voice. The first visit could, however, take all day with easing, full bedding, and some repairs on the way to sampling. But we discuss, estimate, and get paid for such extras!
At the bench, we have one to two hours set up time, depending on whether we have a Regulation Station Deluxe or have to manually contrive positioning and shimming on our bench. We setup the Regulating Rack, fixing to its rail a selection of Templates matching in width the sections of the action and representing the string heights for those sections along the strike line. We set the stop collars on each leg to stop the rail upwardly at strike and downwardly at hammer line. On the profile edges of the Templates (at strike), we record the hammer spacing scale to return hammers to as we proceed with regulation steps that undo spacing.
If the regulation as we find it is very far from target, it is short work to rough in hammer line (rail all the way down), letoff and drop (rail lowered from all the way up using Gauge Keys), and any other work required to get into working range. We then fully regulate a natural and a sharp to validate specs, parts, and materials, giving ourselves the opportunity to tweak geometry or make other changes at the beginning of work, rather than at the end when changes are really expensive.If we are going to install new parts, we install them on a third sample to regulate and compare aftertouch, weight, angles of address and so forth.
So we find out what works well or needs shifting and proceed with the prescribed steps. We file hammers and correct friction. Whippen rep levers may need repinning, particularly if jack return depends on the repetition spring tension. We remove hammers and whippens to an Action Tray, with screws stored in order along the edges. The flared hammers file up quickly at the Hammer Filing Jig - the straight-bored hammers wait to be gang-filed when they're back on and vertical. We pin flared hammers to 9 half-swings and straight-bored hammers to 10 (since they will be lighter when filed). The rep levers are pinned to 5 grams measured at the long end. Then the parts go back on, with hammers spaced to the Regulating Rack and whippens spaced to the hammers.
Next, we set up the Squaring Platform so that its sliding top just clears the backchecks at rest and all four corners are at the same height, i.e., the surface of the Squaring Platform is parallel to the plane of the action. From this surface, we first travel hammershanks to vertical with the Shank Traveler, then make hammers vertical at strike with the Hammer Square (strike provided by the Regulating Rack), and finally space hammers to the hammer spacing scale (also provided by the Regulating Rack).
This takes a little time. All shank travel may be off and all hammers may not be vertical at strike. But think how getting it right simplifies things when we get to string-to-hammer mating! And it saves psychic and emotional energy: instead of having to decide who’s right enough to keep as-is and who’s wrong enough to have to change – a process that may take several passes and will certainly have a slightly compromised outcome – we methodically go one-to-the-next with a yes or a no from the Shank Traveler making all the decisions. In the short term, we trade a slightly frustrating headache for an empowering meditation. In the longer term, we avert complications that may require voicing techniques to mitigate problems only solved by correct traveling, squaring, and mating. Also, we save a step in mating strings to vertical-at-strike hammers, combining string leveling and hammer fitting into one operation.
We are now able to successfully gang-file the straight-bored treble hammers. If tails are all the same length, they can sit on the Squaring Platform’s sliding top. If not (as was traditionally the case with Steinway tails), then we lift all crowns to the same height with the support rail. The gang-filing starts with a wide sanding paddle to establish overall consistency of shape, especially at the crowns. Then flexible strips over two or three hammers at a time finish the job.
We level keys next, squaring and spacing as we go. Keysteps support our leveling sample keys (which were pre-leveled with cut punchings to the right height). Two rounds get us very close. Settle the keys quickly and thoroughly, blocking hammers with the Regulating Rack set at hammer line and applying firm glissandi to sharps and naturals (also to backs of keys). This stabilizes knuckles and whip cushions as well.
If needed, rough in any elements of regulation that are very erratic or very out of spec. Set dip to what the samples indicate, to refine later by aftertouch. Space backchecks and set naturals to check as high as possible without upswing tail-scraping when played against the resistance of your other hand and match sharps. Set spring tension. Set jack position samples and align section-by-section to a straightedge, under-lighting the whippens with a Lighting Rail. Place the Regulating Rack set at hammer line just behind the hammers (with its lights plugged in!) and wink the hammers (set rep height). Now we can set a stable hammerline, do letoff and drop (set up with the Gauge Keys), and proceed with refining aftertouch, dip, and backchecking, using the Regulating Rack.
For some jobs, we are now done. For others, we are ready to weigh off the action. This step adds consistency to action performance and simplicity to voicing. We remove a strategic amount of lead first, drilling out holes, plugging, and trimming plugs. This allows us better weigh-off accuracy and ease of execution.
We match downweight and upweight key speeds, setting up weights to provide clear, positive motion (no topstack tapping). 25 grams upweight in the treble and a minimum of 20 grams in the bass, with an easy, positive lift, result in a very responsive touch. Over 30 grams is too much, under 20 grams is too little. Apart from being fast, the matching-speeds method reveals any friction irregularities, slower lift speeds indicating too much friction, faster, too little.
We flip punchings, paint sharps and size balance holes while the action is apart. Dampp-chaser additive in the balance holes, left to dry overnight with the keys on their pins, resizes away wear caused by regulating.
And then, we can perform a short refinement pass as needed, fast and fun, a polishing of our work…
Now, the action goes back to the piano. If glider studs were used to adjust balancerail support on the bench (the best procedure, if you don’t have a Regulation Station Deluxe), they need to be returned to correct in-piano positions, an easy matter using the WNG Bedding Tool.
Then, we reinstall the action return spring, checking that surfaces are perpendicular and shimming with frontrail punchings as needed if they are not. In the shop, we sanded away any return spring indentations in the keyframe, as they would essentially freeze the treble end of the keyframe and obstruct bedding.
If sampling and setup were done correctly, we have nothing more to do to keys, keyframe, or topstack, with the exception of fine hammer spacing. But if during our traveling and squaring we improved overall spacing by nudging the scale one way or the other, we can now shim or trim the action rest rail to accommodate.
Next, we settle wire, pitch-raise as needed, and mate strings to hammers. Since the resultant leveling optimizes damper function, this work precedes the fine damper regulation, which is next up, followed by adjustments as needed to pedals and trapwork.
Not being bogged down by installation rework and not being overwhelmed with unknown variables of hammer address and fit makes the last leg of voicing and fine-tuning a lot more fun. The general clarity and evenness of tone from the vertical=at-strike hammer fit way simplifies voicing. And knowing the action is correct reduces stress and confusion. Individual hammers have not been misfiled to fit, so soft pedal voicing becomes mostly a matter of adjusting the action stop.
The results exceed expectation. Armed with confidence to end up in the best spot with best results, we have confidence to sell the next job - and sell it for more money!
This linear approach is down-scalable. A fast route through with these priorities understood and respected, still upgrades results from old-style regulating. And the tools look as effective as they are, making them marketing assets. Although the full set of Grandwork™ tools will produce best results, individual tools and partial combinations pay their own way.
Full regulations are under-sold today. Technicians find miscalculations expensive and the learning curve long, if not never-ending. The Regulation Station tools and Grandwork™ protocols reduce the experience needed to succeed at each step of the process and the go-nogo procedures and trial-and-error methodology are fast and accurate. You will find the four Grandwork™ protocols and our Setup and Order of Operations posted on the tprtools.com home page. Please try them out!!