Who knows the standards for piano performance and who pays the bill?
It is necessary to explain things and communicate well to the owner,
because they don’t have the expertise, the tools or the knowledge .
Benefits & goals of regulating
Achieve control
Power; dynamic range
Reliability – improve repetition
Evaluate the condition
Hammers
Key bushings end felts (remove end felts, rout unevenness, replace
felts; steam cawls to soften bushings)
Knuckles (very important; replace instead of bolster)
Backchecks
Action centers (repin instead of lubricate)
Keyframe
Repetition lever coating (to loose? Repin?) 4 grams
Whipp en felts
Touch
Pre-Regulation:
The Three D’s
1. Sufficient key dip (11 mm min.); remove front rail punchings
2. Drop 9turn down)
3. “Dance” repetition springs are strong
Locating and Alignment
1. Locate Action place a screwdrive under the treble end of the keyframe
and slightly lift the keyframe to hear if it improves the tone. If
it does, then add or remove wood from the back of the keyframe by sanding
or veneering.
2. Bed the Keyframe Keep the keyframe sprung. Raise all the balance
rails first to get a clear knock on every one equally. This makes
sure the front and back are tight and the middle is suspended in the air.
Tap on the back rail with a long strong screwdriver, listening for bumps.
Sand the front and bed it, although Steinways have a side-to-side spring
tension built up and is up in the front. At the end, turn down the
balance rail studs just to stop the tap. Thje test is to lift up on the
hammer rail while you tap and you should hear a taping again. This
tell s you that there is still springiness – the rail is still sprung down.
Wikth weather changes, instead of moving with weather changes, the pressure
changes, but the position stays the same.
3. Square, Space and Ease Keys
4. Level Keys
5. Space and Travel the action
? Travel hammers first
? Space the strings
? Space hammers to strings Do two passes – once quickly &
tighten the screws, 2nd time fine. Place the treble hammers a little toward
the treble and the bass a little toward the bass for unachorda.
? Space and travel the whippens (turn the action backwards on the workbench)
Line up whippens to the knuckles. First try tipping the whippen.
If flanges get tipped different ways, go through and straighten them all
out and paper them to prevent scuffing and to keep things in line.)
Remove the hammer stop rail if you need to do a lot of whippen work.
1. Align backchecks to hammer tails. Look at the angle of the backcheck
as it contacts the hammer. First check for the angle surface at rest;
the backcheck and the tail should be parallel. Hold the bottom, place
parallel pliers on the top of the backcheck and adjust it. A check
is to tap on the hammer and drive it in a little bit. It should take
some effort to drive it in. If it drives in too hard or too easily,
it’s out of adjustment. Adjust a sample at the end of each section.
Get a feel for the wire stiffness, then bend them all, matching the feel.
Check with a straight edge. This will take 30-60 minutes.
2. Action Spread Check It’s worth the time it takes to take some measurements.
Normally the rail moves back from the force of playing. If you don’t
have the spec, pick a note and regulate the capstan, drop, knuckle, etc,
then measure down-weight and up-weight and write it down. Subtract
it to get the difference. If you suspect it needs to go narrower,
move it 1/16th and look how the jack lines up. Loosen the screw, bump it
and tighten the screw. Regulate again and see how it is. The
difference between the down and the up should get smaller. If it
gets bigger, go the other way. If you get a low friction figure and the
jack looks screwy, lean toward where the jack looks right. Changing
the spread changes all the leverages slightly. This will change how
the whippens sit on the capstans, etc. but the goal is to get it back to
where the manufacturer had it. Do all this on one hammer like an
action model. Measure the centerpin to centerpin spread, then copy
it throughout the action. To make double sure, you could do a friction
test somewhere else as well. When you have it, write the spread on
a key. Snug the screw rather than squeezing it tight on older wood or the
screw will become loose again.
Space jacks in repetition lever windows.. Lightly tap it in place.
Another more permanent way is to put a bend in the center pin and find
the angle in the jack.
Heart of the Regulation
Jack under Knuckle The notch is to help factory manufacturers set the
jacks quickly. Start by regulating the jack to the mark or the knuckle.
The back edge of the jack should line up. A good pianist feels
this.We want a consistent travel. Regulate it to the core.
Whack the keys with your hand above the hammers and feel for cheating
Repetition lever height. First pass do by feel. The second
pass is done after adjusting the springs; feel how the jacks rub on the
knuckle. The jack should be supporting the knuckles slightly.
Stick with a consistent depth.
Let-off Set samples in the piano. There is a start point where everything is at rest and the key height is the reference point. The limit to the action travel is the strings, so it is important to get this limit even and accurate. Once it is decided, all the other adjustments are set to these constants. Regulate let-off with your eyes on the strings and hammers. Set the key slip on the piano over the hammers, resting across the rim, and rest a little flashlight pointing down.
Determine the best Blow-Dip-Aftertouch specifications. Pianists
might notice a dip that is too shallow. They feel from the point
they hit the let-off button until they feel the after-touch. With
low friction they might not notice a lot of aftertouch but it might feel
too light.
1. First find a starting point. The dip is pre-set at 11 mm,
or whatever the spec is. Manufacturers measure dip from the pin and technicians
measure from the front.
2. Find out the blow distance. 48 would be at the high end.
3. Find out if there is any aftertouch. For regulating purposes,
aftertouch is the motion of the action after the hammer stops rising.
When the hammer gets as high as it goes, the motion after that is aftertouch.
The jack is the indicator point. If the spread is too wide, the jack will
have no room to work at all, and the aftertouch will be minimal.
Generically, the jack should just clear the knuckle and half about an equal
amount of space before it hits the stop felt. There is a learned
feel that determines an amount of drag or clunk.
4. What to change? Minimal aftertouch, increase dip by removing
a punching. In other words, to increase aftertouch, increase dip.
Raising dip on the sharps too much makes the touch heavy, so keep the sharps.
A high leverage action might need more blow distance. If aftertouch
is too minimal, it doesn’t feel like it’s done, because the jack is still
hanging up on the knuckle. If the jack jams too much, a hard-playing
pianist could break a jack. Keep things close to a good feel.
5. Make an aftertouch guage. For miscellaneous pianos where you
don’t know specs and the action dimensions are unknown,like when the balance
rail pins are not positioned correctly so that the blacks and the whites
are not at the same ratio. Be able to have the key go down so it
touches and the hammer doesn’t go down at all, passing let-off just a little
bit. Add more punching thickness and test again. This punching
guage makes it stop at the highest hammer travel, and when you squeeze
it more the hammer drops.
Regulate the capstans Make a tool out of wood. Set the tool on top of
the hammer you are going to regulate and hold it down. The hammer
is regulated just at the right blow distance. Once these samples
are set, either eyeball it in the piano or use a let-off rack. On
a Kawai the hammer height measurement is 46 mm from the strings.
The gauge will be too short in the bass because the the let-off is a bit
lower.
Adjust the drop screws. Set drop by feel. Dip, drop and dance.
If it is a little on the low side, you can play the note slowly, watch
the jack, and feel the drop screw touch. Start with the drop screw
low and feel. There is a sponginess in the low and the high area. The first
time around, raise the drop screw up so the cushion touchs the screw.
This is the lowest acceptable range. This will be close to being
done. Watch the drop. This is pretty good, but will change
after the springs are done. The spec on drop is 1/16th after let-off
after the regulation is done – after the hammer comes back up again.
This spec is for the hammer at rest. Put it 1 mm or 1/16th under let-off.
If the drop is too high, the note won’t sing out. If there is uneven
ghosting, check the jack 7 knuckle.
Regulate the key dip according to aftertouch Use the punching
guage. When not squeezing at all, the hammer is high. When
squeezed, the hammer drops. If it goes up more with the squeeze,
there is too much.
If it lets off all the way, there is too much key dip. Touch
it and it stops, squeeze it and it drops. Remove the gauge and replace
the punchings. Hammer travel and key travel match perfectly.
Regulate backchecks. Use neighboring keys. The Kawai spec is 15mm. Set samples, replace the action and check in the piano. Then remove the action and adjust.
Repetition springs They should be quick and uneven. Don’t kink
the wire. To strengthen it, pop it out of the slot and give it a
little tug. To make a strong change, hold down the lower spring section
with one tool and yank it up with another tool. Don’t change the
shape of the curve, because then the spring will push on a different point
on the wood. All the spring does is to hold the hammer up in the
air while the key is being pushed down. When the key goes down, then
the jack returns. In dry climates, the spring should go faster.
The height of the rise is determined by the drop screw, and the speed is
determined by the spring tension.
Rep levers feel the jack-knuckle rub in the piano check the drop for
evennes by feel.
If the drop screw looks low, look at the key to see if the dip is low.
Look at the jack on the knuckle.
When you see the drop is uneven, don’t just turn the drop screw until
you have checked other things.