Piano World Home Page Forums Our Most Popular Forums Piano Tuner-Technicians Forum is string leveling(lifting) harmfull, even useless?

i have observed　techs at work in many different places, not only at home but also at concert halls, recital prep and anual maintenance and so on.

i always ask them if they plan to do string leveling and seating, answer is almost always "no".

so i ask "why?" and they tell me that can bend the strings, causing false beats, besides the strings will be coming down any way.
some say you can lift strings of relatively new pianos, but not old (10~ years) pianos.
inre seating, they say they are afraid of nicking the wire.
i have seen a tech lifting the strings but never seen someone seating the strings.

pianos are mostly steinway hamberg.

is it that strings of steinways usually dont get driven up off the bridge easily?

though every book about regulaion i have read mention about these two procedure, techs dont seem to care much.
because it is not really necessary?

My understanding is that the strings are meticulously leveled in the Hamburg Factory. Several years ago I had the pleasure of watching Ulrich Gerhardt (head of Steinway concert services in London) prepare a D. He said they never lift strings and do all hammer mating by filing on the hammers.

I have over-lifted strings on a piano which caused some sizzling types of noises. So you definitely don't want to overdo it!

The technique I use now for "seating" strings on the bridge is a gentle stroke with a brass rod, pulling towards the bridge pin, with the tool roughly the same angle as the bridge pin. Although I do sometimes still gently tap strings down on the bridge with a small hammer. Emphasis on gently.

Greetings,
It isn't possible to voice a piano without the hammers being mated to the strings. Removing the curvature of the wire just past the agraffe will often allow the hammer to strike the trichord evenly and is a common first approach. Poorly drilled agraffes will often leave one of the three strings higher or lower than the others, causing the same unfocussed twang.
In some pianos, a hammer must be filed on a slant, since the strings are so out of level there is no way to bend them to mate with a squarely cut hammer. This is a not uncommon problem on N.Y. Steinways, owing to agraffes being installed on a slant.

I have never heard of false beats occuring as a result of leveling strings, and if someone is breaking strings in the process of leveling, then they are using 10 times more force than is called for. Same for "nicking" the wire. It is hard to do, since that is pretty tough steel in the wire.

One reason techs will skip this is that they don't hear the difference. Another is that the damper seating can be upset when a drastic change is made to the height of one string, and who needs the hassle of a bleeding damper? Another reason is that we are inherently lazy, and if the voicing is already uneven, why would clearing up the fuzziness of the unlevel strings be of much use, etc....

There are many jobs in piano work that require fine skills, both in listening to and manipulating the instrument. There is a class of techs that never pay attention to them, since there is no need for the effort in order to get the payment. There is also a class of techs for whom it is never close enough to perfect, and we drive ourselves nuts over picayune matters that few others are aware of. Somewhere in between these two is a way to make a reasonably sane living, (or so I have been told).
Regards,

Yes but they are leveled at the factory, and it is done very well and until it is stable. Then the concert tech is not supposed to have to level them.

But mating the strings on the bridge after the piano have been played sometime is just normal (and correct hammer mating sizzles noises often).

I like to use my hammer (gang) filing as a jauge to know if I have to level some string, but of course I check both.

It is easy to overdo with a string hook, (on strings less than 15 years) but all that can be learned. The long hook made with a long steel wire and installed on a long wooden rod that will apply on the agrafe or the capo is an excellent tool, more precise than the usual hook.

Once upon a time a tech visited a piano store. Excited about something he had just learned - without asking - he pulled a newly fashioned brass tool out of his bag and, with hammer, proceeded to "tap" the curvature out of all of the strings at the bridge pins, asserting the such would make the new grand "settle down" and "break in" a whole lot better. Questions and concerned from the store's tech were largely ignored. He then left the store confident that he had made a dumb old Arkie's job of breaking in the new piano - and via application, all new pianos - a whole lot easier.

The following day, when this new $100M instrument was tuned again (it had already been tuned several times), and these new bends in the strings moved to the speaking side, what do you think the store's tech discovered?

All kinds of wild, crazy new sounds?

The piano needed new strings?

There is a difference between tapping down strings at the bridge, as opposed to what this guy did. If I understood the post.

String leveling and seating are essential voicing steps that can't be overlooked. When there's that one note that just doesn't sound right, check the whippen alignment and hammer travel first.

I've found that saving the hammer felts for last is faster and longer lasting. The quick through-the-strings chopstick voicer is hard to resist.

An aural mess to say the least. What Ed and Ryan state are sound and recognized practice. What this guy did was whack the curvature of the strings at the bridge pins until straightened. Then he whacked them down. It was anything but gentle.

Point being - Pianists: Have a care who you let tear into your piano.

Greetings,
There is only one tool in my tuning kit, other than hammer and mutes. It is a very small string hook. I use it a lot, sliding it along the string for an inch or two before it bumps into the bridge pin. I use a SAT,and it will often show a definite improvement in the stability of the pitch after a light massage. I think it is as much forming a tighter coupling of the pin and string as it may be removing the curvature, but there have been many a false sounding note that cleaned up, noticeably, with this treatment.
I would never do this on a new piano,as there will be migration of string length from the hitch pin back into the string as the other bends reach equilibrium. On older pianos, having suffered many humidity cycles and oxidation,and who knows what else, it can make a lot of bad noises go away. It will often cause the pitch to drop by a cent or so, which I ascribe to a straightening effect.
Regards,

Everything can be overdone. Very aggressive "string leveling" can put kinks in the wire. As to whether this actually causes false beats is certainly debatable. Properly done, string leveling does not damage the wire.

Seating strings on bridges can be, and often is, overdone as well. The bridge pins form a semi-rigid termination to the speaking length of the strings. There are two parts to this termination; the pins themselves are angled so, in theory at least, the strings are held tightly against the bridge cap and the strings are deflected from side-to-side by the offset of the two pins.

It is a common misconception that the vibrating motion in the strings causes the strings to ride up on the bridge pins. This is not the case. Gaps appear below the strings over time as the wood from which the bridge caps are made expands due to climate changes and presses against the bottom of the strings. As mentioned earlier the pins are angled to one side and, being relatively long, they are anchored to the core of the bridge body. During periods of high humidity that angle prevents the strings from moving up on the pins so the wood underneath the strings is slightly compressed (i.e., compression set). When the bridge cap subsequently dries out and shrinks a gap appears. If the strings are tapped down at this point the cycle will simply repeat itself through the next change in climate. This, by the way, is a good argument for resin-saturated laminated bridge cap stock. It may be ugly but it works.

ddf

Del,

Are you referring to an epoxy laminated cap and/or Delignit, or just the epoxy lam.

I'm thinking of Delignit for my next cap, as I built a machine notcher...the carbide head allows the use of Delignit with impunity. Do you have any experience on the moisture cycling differences between these two cap substances...epoxy lam and delignit?

Jim Ialeggio

On the string leveling question, that is, leveling the plane of the strings, I have been skeptical of what can be accomplished and how long it lasts.

I am referring here to string leveling...massaging the strings at the capo/agraffe, and not string mating which, in my book, is adjusting the hammer to the string plane once the string plane is accepted as given.

I have dutifully messed with string leveling at the capo/agraffe I am getting closer and closer to abandoning it altogether except for gently massaging lifting new strings at this location. I hear techs going on and on about how essential it is to do this leveling often. Mostly, I think it is done so often, because if the leveling last longer than it takes the check to clear I'd be very very surprised.

String mating, that is mating the hammer to the given string plane, yes, is long term, however repeated massaging of the strings at the capo/agraffe...not so much I think.

My experience here may be related to the fact that string mating is just not as critical on responsive boards with cold pressed hammers, as it is with challenged 5th-6th octave pianos and hard hammers.

Jim Ialeggio

Pretty much all of the above. I started out with a bias toward laminates built up using epoxy as the adhesive—still have one for purely aesthetic reasons—but experience has demonstrated that any reasonably rigid, resin saturated laminate performs about the same. That is, laminates put together with an adhesive based on resins such as phenol, resorcinol (used in Delignit pinblocks and bridge cap stock) or urea; they all work about the same as long as plenty of the stuff is used. The idea is to saturate the substrate and create something along the lines of a fiber-reinforced plastic material.

Of all of these my preference leans toward epoxy or urea-formaldahyde adhesives just because the color is relatively neutral. Resorcinol gives the laminate a dark reddish-brown glueline that doesn't really add to the aesthetic value of the bridge cap. Although I have used it and, from a purely functional standpoint, it does work pretty well. I've also done a few using Titebond II and Titebond III that seem to be working just fine in spite of everyone's concerns about excessive long-term creep.

And, while we're on the subject, while Delignit works just fine I still do prefer to make my own bridge cap stock because I don't like fully cross-laminated—i.e., with laminates laid at 90°—stock for bridge caps. Typically my lay-up has the plies laying at more like 15° to 30° relative to each other. Usually this means the top layer is running roughly parallel to the bridge line, the next at 15° one way and the next at 15° the other way and then repeating the cycle. Or, put another way, one at 0°, one at -15°, one at +15° and then back to 0°. To be sure, this is a compromise but the notches sure do look better and it works a whole lot better than solid stock.

ddf

I agree. I rarely spend more than a few minutes “leveling” strings. About all I do is gently massage them from below—if I can get there—with a simple brass tool that does all three strings simultaneously. The idea is to just even out the bends at the bearing point; not eliminate them. They are change anyway as the piano gets tuned. I suppose one could set up an endless cycle of bending, tuning, bending, tuning...and on and on and on...but what's the point?

The rest—if required—is done at the hammer. But, as you say, with lighter soundboards, lower-tensioned scales and softer more resilient hammers not all that much is either necessary or useful.

ddf

String leveling? Tapping at the bridge? Seating at the capo?

I have attended classes by many of the major piano manufacturers for many years at the PTG conventions. EVERY builder suggests a minimum of seating the strings at the bridge, and leveling at the hammer strikepoint before any voicing work can be done. Techniques vary, but those are absolute with all of them.

Whether you watch Don Mannino (Kawai) tapping strings at the bridge with a jack out of a Millenium action, or Yoshi (Yamaha) with a brass drift, they all believe in the value of seating and leveling; and present this as a standard approach to regular maintenance of high-level concert instruments. Don even designed a string-lifting tool to help with the job...is it Schaff or Pianotech that offers that one?

Fazioli may level the whole damn piano before they level the strings, but they also insist on the value of leveling and seating before voicing and hammer-mating. Kent Webb (Steinway) also presented string leveling and tapping at bridgepins to insure good hammer contact and energy transfer. Frankly; I don't recall a high-level instrument or voicing class that did not insist on getting these things done BEFORE shaping, hammer-mating, and voicing.

I ain't gonna argue with these folks. AND I firmly believe in the benefits of the procedures from my own experience. The fact that my favorite dealership insists on spending MONEY to tap the strings and seat them on every new piano they sell, because they see it as a benefit to tuning stability, voicing, and customer satisfaction, ought to be considered, too.

Off the soapbox,
I am,

If you stretch a string past the deformation limit, you will ruin it. If you do not stretch it past the deformation limit, it will go back to where it was. So the idea of string leveling by pushing on strings is either harmful or useless. However, strings can be helped to get seated. It will happen by itself, though.

Absolutely

And when you tune a piano that is used in concert you may need to seat more strings than expected.

the tail of a grand long bass hammer is a good tool for that, no risk to marr the plate, when not using it so can be used during tuning.

About the "retuning" after using the string hook, once the strings are stable, the hook does not really put out of tune an unison. Not much , in any case.

Del,

I had a very frustrating experience with an attempted veneer laminated cap, via Nossaman style, this past winter. Laid up several 12"x 8'x 8mm 12 ply veneer cap first with MAS infusion epoxy (under 200 cp), then a second with West system, both in a vacuum bag. While they looked great, when I put the glue joints through the test to destruction test, the laminations failed the inter-layer test. This means I could achieve failure of the joint between layers of veneer without harming the wood, or getting at least significant fibre failure when levering the layers apart. I finally, after quite a bit of time spent trying to get the whole thing working, abandoned it and did a 3 layer titebond cap...very frustrating. I believe I also ran some experiments with just light pressure and no vacuum bag. These also failed similarly.

Completely baffled me, unless the ultra dry air of mid-winter had something to do with it, ie the wood completely sucked all the resin out of the joint and into to fibre.

Any thoughts on a fix for this failure?

Jim Ialeggio