Lubrication of Piano Parts

When pianos are built, the builders concern themselves with lubrication of moving parts in a rather fundamental way. They are concerned with new material assembled under controlled atmospheric conditions and lubrication is a very minor consideration in construction process. Obvious friction points such as those in the trap work are greased or graphited. In that complicated mechanism called the action, many friction points are treated with a permanent lubrication such as burnished graphite or were designed to be self-lubricating through use of felt against metal or, more recently, teflon against metal.

When the pianos are completed and shipped, further thought is not given to lubrication since factory people generally have no other contact with the instruments. Once the pianos are sold, however, a whole new set of problems begins to develop, including wear and tear, atmospheric extremes, abuse, and neglect. Lubrication is also one of these problems.

The word “lubricate” comes from Latin lubricare, which means “to make slippery.” The trick with piano friction points is to make them slippery and keep them slippery for extended periods of time. A lack of lubrication creates two general problems - sluggish response of moving parts and noise in the form of squeaks.

The anatomy of the piano creates other problems. There are no reservoirs to store lubrication such as oil pans or grease cups. Instead, the lubricants often must function between dissimilar materials, usually as thin films while exposed to accumulating dust and dirt. They must hold well through periods of use, must break down during disuse, and must not react with the host materials by creating any chemical change.

With the above criteria in mind, let examine the materials used as piano part lubricants. They fall into two general categories: (1) Solids and powdered solids include soapstone, talc, graphite, and teflon. (2) Liquids include tallow, grease of various kinds, and liquids that utilize some of the powders in suspension. The list of liquids must be expanded to include the sprays available today that have proven to be useful and time saving.

Many years ago one of the standard lubricants for piano parts was mutton tallow into which was stirred a fair amount of talc or baby powder. With the demise of the neighbourhood butcher shop, mutton tallow has been difficult to acquire. However, if you know a butcher who can get you some mutton fat, you can make a life-time supply of mutton tallow lubricant very inexpensively. Simply put the raw fat in a frying pan and fry it at low heat until it turns to a liquid. Skim or strain the liquid so as to separate it from any fiber residue and allow it to cool. The tallow will be a white waxlike grease. An additional reheating and skimming will improve the quality by leaving behind any missed residue or poor-quality fat. Into this refined tallow stir as much Johnson’s baby powder as it will hold without losing its consistency as a grease.

A contemporary substitute for mutton tallow and talc is... 

 

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Tuning By Plucking

One useful technique I forgot to mention in last month’s blog post on treble tuning is plucking. If you are having difficulty hearing a unison or even an octave in the high treble, then pluck the strings and listen to the relative pitch.

This approach, in combination with the key, may help clear things up a bit. (If you have not read my last post, I suggest you do so to maintain continuity with this one.) Every note must be tested until you know that it is right, or as right as possible, before going on to the next string. This applies to every aspect of tuning, temperament, treble, and bass, and cannot be overly stressed here. After completing the temperament, I start tuning the bass by tuning E3 so its fifth (B3) is as pure as possible without an overly rough fourth (A3), and so the third (G#3) and sixth (C#o) retrogress evenly relative to their adjacent intervals.

I have found the third/tenth test useful, but none of the above are as important as the sound of the octave itself. 

The one thing that does come out rather rapidly is an error in the temperament. One obvious error is the slanted temperament. This is my term for the temperament where everything appears to work out well but the thirds progress too slowly or too rapidly - as shown by roller-coastering of the retrogressive thirds. If the roller-coastering is minor it can be ignored (but remembered for correction at the next tuning). If the error is excessive, then the temperament must be retuned. If the first few thirds going into the bass are too fast, the temperament slope is ... 

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Key-Weighting and Tuning

My customer and piano teacher Jennifer C. from London Kensington asks:

How can I improve the tuning with key-weighting on my Yamaha C3?

Answer:

Dear Jennifer,

This blog post is intended to suggest a possibly lesser known “aid” for tuning the entire piano. Not included in this discussion are such basics as temperament, tuning checks to use, methods of tuning and electronic instruments if one is used. This article will focus on “fine tuning” a piano that is already at the A440 pitch level and in fairly good, even tensions in all sections. While tuning certain pianos, particularly the older uprights, all of us have encountered certain strings, usually the longer tenor ones, that suddenly start to ring or sound while tuning due to sympathetic vibration. It was exactly this situation that prompted further study and the exploration of these “open” strings as an aid in aural tuning. It was further noted that the more in phase the octave being tuned, the louder and clearer the sing-through sound created by sympathetic vibration. 

This blog post assumes that the reader also understands at least some of the physical characteristics of vibrating piano strings, their modes, partials and inharmonicities. The principal of weighting keys is to deliberately raise the damper, freeing the string to sound sympathetically as related intervals are being tuned. The louder and clearer the sound of the weighted-open note, the better in tune the interval being tuned. This is the main principle of the system. Primary intervals used in key-weight tuning are the octave, fifth, octave fifth and the double octave fifth. We hope to stimulate enough reader interest for many to actually experiment with the use of key-weighted open sounding strings in tuning. 

One very discriminate college piano teacher once remarked, “I am more interested in the fifth being in tune than the simple octave.” Of course, what she was favouring was...

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Advice for a Tuning Setback

My friend Peter W. from London, Ealing who is a novice piano tuner asks me:

In the last few months, I have been having a setback in my tunings. I am experiencing a problem which is adding an extra hour onto my one hour and 45 minute tuning time. 

I am assuming I am doing something wrong. I set the temperament first then usually do the bass next, but because of this problem I go first to the tenor and treble, and sometimes do a pitch raise in the high treble section (after the last break). By the time I complete the bass section, my area above the temperament is flat and occasionally my temperament is out. 

My experience is different with each piano, but as always the treble section after the last break is always flat. This is always a problem when the pitch is 5 cents flat or lo-20 cents flat. Any piano which is over 20 cents flat I do a pitch raise and then a fine tune and I still encounter this problem. I always set the pins and pound out the keys to settle the strings. 

Can you tell me what I may be doing wrong?

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https://www.professionalpianotunerlondon.co.uk/post/advice-for-a-tuning-setback

Piano Tuning Problems in the Upper Register

My customer Kathy M. from London, Fulham asks me: 

"Can you explain more about this tuning on the treble section? It doesn't really help the sound quality! If so, can you solve the problem?"

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https://www.professionalpianotunerlondon.co.uk/post/piano-tuning-problems-in-the-upper-register 

Rebuilding Whippens

Recently much has been said about the proper definition of a rebuilt piano. The older parts do not have to be replaced but must come up to the standards set by the manufacturer for the new part. I would like to concentrate on one part frequently replaced by rebuilders - the whippen. There are several reasons that I have not to replace parts but to rebuild them instead.

First, there is the convenience of not having to adapt parts possibly not made for the particular piano or that are not the same quality or size as the originals. Secondly, because of excessive action noise caused by teflon - I simply refuse to install Teflon bushed whippens into an old Steinway. Even if no definite clicks are present, there is still detectable noise in teflon whippens.

The ultimate product of a note played on a properly pinned, bushed and regulated piano is simply a bell-like tone escaping from the instrument with no evidence of mechanical means; and this can be more closely achieved with a cloth-bushed whippen.

Prior to regulation, a properly restored whippen saves on regulation and troubleshooting time, with no action noises to track down.

Lastly, the intrinsic value of the instrument, which may not be an antique now, but may be in 50 years has to be considered. Basically, antique collectors see the most value in a piece that has never been refinished or changed by a later craftsman. The highest prices paid for an antique of any sort are those for pieces in original condition. This has to be tempered of course by the function of an instrument. We want a piano to be playable with the least amount of change in the original design so that future generations will have examples of late 19th and early 20th Century instruments as close to the original as possible.

The first step is to space the hammers to the strings. This will insure that after removal whippens can be replaced accurately. Number all whippens upon removal. In many cases you will be replacing screws with a slightly larger one for a tight fit, but if you plan to save them keep them in order.

Usually an initial dusting off is required just forclose examination of the part. This can be done prior to removal with an air compressor of after removal with a soft paint brush by hand. I use three-sided action trays with a row of numbered screw holes in the back for easy transportation of parts around the shop. Remove all felt and cloth that you have determined has to be disposed of for reasons of wear, moth holes, etc. Clean the spring slot with a toothpick or other wooden scraping tool and regraphite with a No. 3 pencil. Examine the spring to determine if it is too severely bent or corroded to use. New springs are available from supply houses. Remove the centre pin first if one exists (some only have the cloth bushing) and ream the hole.

The new spring should be threaded on the bushing cloth as it passes through the hole in the wood. Usually the springs can be cleaned with either very fine steel wool or metal cleaner. Use of the metal cleaner (Noxon) avoids any possibility of scratching the surface of the spring that rides in the slot.

Frictionless contact between the spring and the slot is crucial. Many times the reason the spring does not make the hammer walk up properly is that ...

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Pre-Voicing

When confronted by tone problems, many piano technicians seem overly anxious to find a quick remedy by using voicing needles or lacquer. Both needling and lacquering are important elements in the over-all voicing picture; a skilled technician must know when and how to use voicing needles, as well as how to prepare and use lacquer solutions for hammer hardening. The point is this: both these methods are ultimately destructive to hammer felt, and shouldn’t be used until all other possible solutions have been explored. What are some of the things to check before we begin to needle or lacquer?

A. Before thinking about voicing we must make sure the piano is well tuned. We all have had clients comment upon the remarkable change in tone or volume after a good, solid tuning. A major pitch change will most assuredly change a piano’s voice, so tune it first. As part of our preliminary tuning procedure we must consider several areas which can affect tone:

1) Tighten all plate screws.

2) Seat strings properly, using a wooden or brass tool to tap them down on bridges, aliquots, duplex bars, and counter-bearing bars. This can clear up false beats, and clean up a muddy sounding tone.

3) At this time, check and, if necessary, correct the tuning of the duplex scale - if the instrument has one. You may notice a brighter, louder tone when the duplex strings properly reinforce the harmonic structure of a given note.

4) We also double check the location and tension of stringing braid. A minor point, but one which can either add or eliminate high partials without using needles.

B. Next, we consider the role of proper action regulation in piano tone-building. Perhaps this is an obvious point, but sometimes we overlook regulation problems and are quick to blame hard or soft hammers, old strings, etc., for tonal problems. Some areas of regulation seem to have a greater effect on the tone we hear:

1) Of primary importance in this area is the bedding of the keyframe. This foundation for all our regulation has a very direct influence on what the artist hears, both physically and psychologically. Generally, an improperly bedded keyframe will cause loss of power and consequent loss of tone.

 2) Another major item to check here is the proper hammer striking point, especially in the high treble. Many a hammer has been unnecessarily hardened, when the problem was really an incorrect strike point. Check by experimenting- results here are immediately obvious.

3) Travelling of hammers and shanks can affect tone, so do this work carefully.

4) Of utmost importance is the actual hammer-string contact point: each hammer must hit its strings squarely and simultaneously. Space the hammers to the strings. File the hammers if necessary to remove dead felt, and to provide a perfectly level surface at the strike point. Later, we will discuss filing to bring up volume and brilliance.

After checking that the hammers are level, we check for level strings. String levelling is much over-looked, both by manufacturers and technicians. Here is an area that can dramatically improve tone. The symptom of an unlevel unison is an unclean, almost buzzing sound. It can also seem like a false beat, and can make tuning difficult.

Check all unisons by pulling the hammer up to the strings and blocking it there. Use either a hook to support the shank from the bottom, or use the method of pushing up on the bottom of the jack and not allowing let-off to occur.

When the hammer is blocked in such a fashion, the strings are individually plucked. It is immediately apparent if one or more strings is not level. The high strings will sound, while low strings will be deadened by the hammer. Carefully lift all low strings to the level of the high strings. Use a tool available from supply houses (string lifter) or make yourself a stringing hook using heavy gauge music wire epoxied into a handle of some sort. 

In string levelling we are actually pulling up and slightly bending the wire near the agraffe or cape bar. This technique is easily learned and is an important part of pre-voicing. (An added bonus of level strings comes when we regulate dampers- especially in fine adjustment of the tri-chord wedges.)

C. The piano can be well tuned and properly regulated, but still lack volume or brilliance. Don’t lacquer yet. If there is plenty of felt on the hammers, another filing can increase tone quickly. Getting down closer to the hammer molding, the layers of felt are harder and can create a more brilliant tone. This is especially useful to bring up sound in the high treble.

Some manufacturers count on the technician to remove...

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