Aim for the Best Voice

Follow the Grandwork System and use its tools to excel at grand regulating. Succeed at your voicing by addressing hammers to strings vertically, also optimizing repetition, power, and tone. And work accurately on a bench to better see, reach, and enjoy your regulating.

In Dale Probst's words: "The Regulation Station brings grand action work out of the cave."

Bed and Sample

With shanks off rest cushions and no excessive friction, start bedding with a fully-assembled action. Remove the action return spring and sand out any indentations in the keyframe. If the backrail or the frontrail has a bedding problem, follow the Grandwork Bedding Protocol. Otherwise, bed the balancerail using the WNG Keyframe Bedding Tool, pedals fully depressed.

Next, employ Keysteps to sample bedding and use a WNG Dip Tool for weighted samples of strike (see the Grandwork Sampling Protocol). 

Set Up

On the workbench, fix action position and shim frontrail and backrail to be stable. Regulation Stations with a Custom Keybed make this easy! Set up Regulating Rack templates to represent string heights along the strike line and set stops on the legs so all the way up is strike and all the way down is hammerline. On the templates at strike, record the Hammer Spacing Scale and with the String Height Gauge, record end-of-section template heights.

With the assistance of Gauge Keys, fully regulate a natural and a sharp to validate specs, parts, and materials. Tweak geometry or make other changes while still chargeable as extras.

Remove hammers and whippens to an Action Tray, storing screws in order along the edges. File flared hammers with the Hammer Filing Jig. Pin hammer flanges and repetition levers as needed. Then, with parts back on, space hammers to the Hammer Spacing Scale and whippens to the hammers.

Make Hammers and Hammer Travel Vertical

Set up the Squaring Platform (see Grandwork Alignment Protocol), traveling shanks to vertical with the Shank Traveler and squaring hammers to vertical at strike with the Hammer Square (strike provided by the Regulating Rack). Finish by spacing hammers to the Hammer Spacing Scale (also provided by the Regulating Rack) and then gang-file the straight-bored hammers.

For installing new hammers, add Hammer Hanging Jig to Squaring Platform after traveling the shanks. Set up the hammers at strike and employ the Hammer Square Lite to square to vertical as you go.

For best results, use the Regulating Rack to measure bore distance (from strike to hammer centers) before boring hammers. Cut overall hammer length based on these measurements and bore from the tails. This custom work ensures that all aspects of the regulation and string-to-hammer mating work properly.

Level Keys and Regulate

Level keys next (on the workbench), squaring and spacing as you go. Keysteps, pre-set in the piano, support the leveling sample keys, which support the straightedge. Level sharps and naturals in the same passes, settling keys thoroughly before and after each round.

If needed, rough in any elements that are very out of spec (see the Regulation Protocol) and set dip to what your regulating samples indicate (to be refined later by aftertouch). Space backchecks and set naturals to check as high as possible without upswing tail-scraping. Set sharps to match naturals. And set spring tension, now that the backchecking height is correct.

Then, set jack-to-knuckle position, regulating to samples using an 18” ruler and under-lighting with a Lighting Rail. Place the Regulating Rack set at hammerline (with lights plugged in) just behind hammer crowns and wink hammers to set repetition height. Now, set hammerline, letoff (measured with Gauge Keys), and simultaneous double escapement (validated by drop). Finally, refine aftertouch by dip and backchecks by playing hammers into check off the Regulating Rack.

Weigh Off

For some jobs, you are now done. But for others, you are ready to weigh off. This step adds evenness and further simplifies voicing. 

Using the WNG Key Gram Weight Set, match downweight and upweight speeds for each key, choosing downweights and upweights that provide clear, positive motion (no need for topstack tapping). Apart from being fast, matching speeds reveals any frictional irregularities, slower indicating too much friction, faster, too little.

Then, a refinement pass, fast and fun, a polishing of your work…

Return to Piano

Reinstall the action return spring, checking that bearing surfaces are perpendicular and shimming the spring with frontrail punchings if they are not. 

If glide bolts were used to set balancerail height on the workbench (the best procedure without a Regulation Station Deluxe or Full Monte), return them to correct in-piano positions, an easy matter with the WNG Keyframe Bedding Tool.

Then, settle wire, pitch-raise, and mate strings to hammers. This string leveling optimizes damper function, so fine regulate the dampers next, followed by pedals and trapwork.


For both piano technician and customer, the results will exceed expectation. And achieving these results grows a confidence to sell more jobs - and sell them for more money!

Full regulations are undersold today. Technicians find the miscalculations of traditional regulating expensive and the learning curve long. The Grandwork System reduces the experience needed to succeed at each step and its go-nogo methodology breeds speed and accuracy. Win win!!