For piano tuners, the smallest difference in weight, leverage, and shape of the tuning hammer is significant, and the way that the socket fits on the tuning pin (or how the diameter taper profile matches that of the tuning pin) is of great importance. Before 1880, there were substantial variations in tuning pin sizes and shapes (square and oblong) that existed between sets, whereas the modern tuner has to contend with variation in sizes between small vintage European pins to the plethora of pianos restrung with oversized pins.
Tuning hammers are the tool that piano technicians pick up the most often; it is used for tuning, stringing, and in voicing the piano. Because of this, tuners develop a sensitivity to the hammer and pin, and can have an awareness of the subtle differences that distinguish one tuning hammer from another.

Burkhardt Shudi (1702-1773) was a famous English Harpsichord maker, born in Switzerland. Shudi family portrait in 1742 by Carl Marcus Tuscher. Burkhardt (tuning harpsichord with “T” Hammer), Katharina, and two sons Joshua and Burkat. National Portrait Gallery.
Early tuning tools were in the form of a “T”, with a striker on one or both ends of the handle, for the purpose of driving the tuning pins into the pinblock (or wrestplank), done in the process of string replacement. This illustration is one of the earliest depictions of a tuning hammer that I have found, drawn by Father Mersenne (L’Harmonie Universelle) in 1637. The instrument is basically a Flemish style harpsichord. Note the hook on the top of the handle, which was for making the braids and loops on the hitch pin end of the string, opposite from the tuning pin. Some “T” shaped pre-1860 tuning tools had this additional hammer function; while modern tuning tools are actually long single levers, the use of the term, tuning hammer, was retained.

Stimmhammer in original square fortepiano. Photo by Walther van der Heiden, Markneukirchen, Germany– Instagram.

Early “T” style tuning hammer with stringing hook, for an early fortepiano or harpsichord, which was found in England. The width of the oblong socket is 4 mm.

Somewhat naive and disproportionate drawing of tuning hammer in Diderot’s “Encyclopédie,” Volume 5. “Lutherie.” (1767) plate 17.
These tools were typically provided with the instruments at purchase, along with a small supply of strings. There was no standardization of tuning pin size at the time, which is why the socket was tapered. Stringing hooks were often removable, and were used for making the loop and braided end of the single strings on these early keyboard instruments.
‘Tuning hammers’ such as this example, were one the early examples of the concept of a ‘multi-tool,‘ capable of performing three operations in a single tool.

1720 Bartolomeo Cristofori double-action fortepiano, the oldest surviving piano in the world. New York Metropolitan Museum.

Late 18th/early 19th century British hammer. A few very similar examples have surfaced over the years.

Very small 1840 Broadwood tuning key and tuning pin; later 19th century pin and its appropriate tuning hammer. (photo by “weeT” in the pianoworld.com forum).

Tuning hammer, with faceted shaft and no stringing hook, 17th, 18th centuries. From Cleveland Museum of Art.

Two “T” Hammers: (l.) with ebonized mahogany handle and beautiful faceted/tapered shaft. (r.) with a 5.5 X 7 mm. oblong socket, and string hook, from Continental Europe.

Illustration of square and rectangular (oblong) wrest pins, in Giorgio Armellino’s “Kunst des Klavierstimmens,” p. 69, 1881 edition; Fig’s. 14, 15, 1857.
Degree of taper in the sockets of these antique hammers vary, which is another factor for measuring the size of the socket. Some are not tapered. The old tuning pins were much smaller and had a rectangular or oval top. There was no standardization, and the pin size and shape could vary.
Armellino described the becket, or ‘perforation,’ as he called it, as either completely bored through the wrest pin, or partially bored. Many tuners preferred the partial bore, according to Armellino.
Going back further in time, the the heads of the earlier tuning pins became increasingly more of a narrow rectangle, eventually resembling the wrest pins of early 18th century harpsichords, and there was no boring, or becket at all.

Two early Tuning Hammers, as depicted in Giorgio Armellino’s “Kunst des Klavierstimmens.” 1st edition was published in 1857, and a 2nd edition in 1881, but Armellino was describing and depicting the earlier versions of tuning hammers. Fig. 6 was the oldest, made of iron entirely, with narrow oblong socket. Fig. 7 was taller, for better access while tuning uprights (pianinos), according to Armellino. Fig. 7 has a square socket, and a wooden handle. Both hammers have a stringing hook, which Armellino opined, interfered with the tuning process, despite making the tool more versatile. He preferred a “T” hammer without the stringing hook for exclusively tuning.

Making hitch pin loops with somewhat antiquated (by 1881) iron “T” hammer “Kunst des Klavierstimmens,” by Armellino, p. 68.
“Both figures, [6 and 7] incidentally, represent the old, common hammer, which, while attempting to meet all necessary requirements on its own, is therefore the most widely used, but leaves much to be desired in some respects precisely because of its versatility. Its hook, located at the top center of the cross and intended for turning the string loops, makes it indispensable, but it is very inconvenient during tuning, where the hand must rest flat and firmly on the hammer and exert considerable pressure. Therefore, a hammer with a wooden handle is often used for tuning, as shown in Fig. 8.” p. 62

Early steel tuning hammer, c. 1800, with narrow oblong socket, 4.5 X 6 mm. This was a fairly common size in the early 19th century.
Claude Montal
A depiction of equipment for tuning the piano, from: L’Art d’accorder soi-meme Son Piano: Une method sure, simple et facile, deduite des principles exacts de acoustique et de l’harmonie, written by Claude Montal, a French piano tuner, and later, manufacturer, in 1836 and 1865.

Advertisement of 19 May,1836 in the “Journal des débats.” From
Claude Montal Commémoration nationale
Key to Montal’s 1865 plate of tools.
From left to right:
- Metal tuning hammer oblong socket
- Square socket
- Wood-handled tuning hammer, removable tubes—for oblong and square pins
- 3 types of mutes, for silencing certain strings during tuning: 31 for squares; 32 grands; 33 uprights
- Flat-nosed pliers
- Music-wire gauge
- Piano-wire cutters
- Hand vise
- Tuning lever, gooseneck, with stringing hook
- Components for universal style tuning hammer, with six interchangeable attachments
- Two tuning forks: diapason and case, #34 used to draw between the tines to sound the pitch, and #35 Diapason Normal A435
- looping/braiding machine

Very early A 422 tuning fork, along with a French pin vise, practically identical to the pin vise shown in Montal’s 1836 plate of tools.
Illustrations in the bottom right show loops and braids being made for the single strings, and then in the lower one the string being wound on the pin, which does not have a string becket and hole (as in modern tuning pins)
Montal’s Plates of Tools: 1836 and 1865 Editions Compared
Montal changed the numbers of his figure drawings: 1836 edition ranged from 15 to 28; 1865 edition ranged from 27 to 43; this was just the sequential numbering of illustrations. The 1865 edition, as expected, had a larger range of tools. Many of the tools remained unchanged between 1836 and 1865, but the loop making machine was updated, with the version pictured in 1865 having been produced for many years by the Estève/Pinet piano supply firm. Also, the music wire measuring gauge appears to have been updated, reflecting changes in wire production over the intervening 30 years.
There were three new tools added to the 1865 plate of tools, two of which were of significant consequence. A new tuning fork was added, “Diapason Normal” A435, which would have reflected the attempt to standardize musical pitch in France in the late 1850s. Since Montal changed his reference note in his tuning instructions from A in 1836 to C in 1865, most likely this would have been a C517 tuning fork.
Authors of the French decree of 1859, endeavored to establish a uniform pitch in France of A435, later known as “International pitch.” The French physicist Jules Antoine Lissajous had observed in 1855 that, “…the pitch varies not only from town to town and country, but it changes in one country and in one theatre from year to year.”
The French commission included the following people: J. Pelletier, President, F. Halevy, reporter, Daniel Auber, Hector Berlioz, Despretz, Camille Doucet, Lissajous, General Mellinet, Giacomo Meyerbeer, Ed. Monnais, Gioachino Rossini, and Ambrose Thomas.
“On the 1st February 1859, the Commission handed its report to the Minister of State. This report was followed by a decree dated the 16th of February 1859, fixing for France an official pitch having 870 simple vibrations per second at 15 degrees C., and known by the name of diapason normal or normal (standard) pitch.”
–“A Practical Manual for the Piano and Harmonium Tuner,” by E. Nugues, H. C. Pouget, and Ch. Martin, published by Leon Pinet and Co.
Another remarkable addition to the 1865 edition was the Universal Tuning Hammer, with six interchangeable attachments, including two lever shafts: one with square socket, and the other with two oblong sockets. During the 1840s and 1850s, the Universal Tuning Hammer, which afforded the tuner greater flexibility and versatility, found acceptance within standard practice of the trade.
The Clef Courbée (curved key) was included in 1836, and remained unchanged in the 1865 edition, although, the view of the square socket, shown in 1836, was omitted in 1865.
And last, but not least, was the addition of the upright tuning mute, the familiar wooden split wedge on a long thin stick covered in deerskin at both ends: this type of mute is still made today, and is used by many tuners currently. The introduction of this tuners’ wedge reflected the burgeoning prominence of the upright piano by the year 1865.
Emergence of the Tuning Lever
As the piano developed, beginning with the later working years of Beethoven and Schubert (c.1820~1830), the tuning pins became gradually larger, and driven more tightly into the wrestplank, which then required more torque to turn them in the tuning process. This meant that more leverage was required.

A young woman was tuning a reference note on a square piano with a “T” hammer, while a French horn and Harp player checked their own pitch. From the title page of Montal’s “L’Art d’accorder,” 1836 edition.
For several hundred years, clavichords, harpsichords, and later, fortepianos were tuned with the traditional “T” hammer, which, in North America, has been relegated to restringing and string replacement since the Reconstruction Era. Anyone who has spent some time tuning harpsichords and other early keyboard instruments will know that the original “T” hammer configuration holds some intrinsic advantages: when tuning with a ‘key,’ all of the energy involved is happening directly above the tuning pin, and with the size of the human hand, and its opposable thumb, equal pressure can be applied on each side of the fulcrum. –Essentially with a simultaneous ‘push’ and ‘pull’ motion.

Introductory page illustration of what could be Montal, in his younger days, tuning a small upright piano with a “T” hammer, and a French horn player and harpist nearby. From Montal’s “L’Art d’accorder,” 3rd edition, 1865.
In contrast, when tuning with a lever, there is pressure exerted on only one axis, and that pressure needs to happen much further away from the fulcrum of rotation for sufficient leverage; if left unchecked, this can result in pins bending over to the side, when a lot of torque is involved. Of course this happens with pianos, but it can also happen with harpsichords, as I discovered first hand, when I briefly tried tuning a few harpsichords with a dedicated lever. That experiment did not last long for me.

From “History of the American Pianoforte,” by Daniel Spillane, published in 1890; page 165.
In Daniel Spillane’s “History of the American Pianoforte,” pub. 1890, Spillane wrote” “…John Cutts Smith was granted a patent for a tuning-key on November, 14th, 1838, which was probably the first contrivance to closely anticipate the present lever hammer…”
Thanks to Larry Lobel, RPT, for bringing this to my attention,
John Cutts Smith, of Boston, MA, described the details of his patent, which featured a ratcheting device enabling the tuner to adjust the rotation of the tuning pin socket without needing to rotate the lever, or once the tuning head/socket is already mounted on the tuning pin, to rotate the lever to a preferred position without having to lift the tuning hammer completely off the tuning pin.
Additionally, the tuning hammer has a thumb-operated lever, or pawl, which locks the rotation of the head/socket assembly, and allows the tuner to sharpen (clockwise) or flatten (counter-clockwise) the pitch of the string.
But, as Daniel Spillane stated, it was the lever configuration that was important, rather than this ratcheting mechanism, which was also tried in later patents, including one from 1873, mentioned later in this page.
Was J.C. Smith’s tuning lever the catalyst for changing from a “T” hammer to a tuning lever for standard practice in Piano Tuning, circa 1840? I think several factors were afoot, not the least of which was the introduction of the cast iron piano plate, heavier strings, and much greater torque needed to turn the tuning pins. At some point, in working with the “T” Hammer, the strain of surmounting a tuning on a mid-19th century piano with increasingly hard to turn pins, would have become untenable, and the logical advantage of increased mechanical leverage would have become universally apparent.
“[Tuning hammers] with a long handle [are] generally preferred for tuning, for the reason that it does not tire the wrist and hand, and with it, one can tune more accurately. A good article costs about five dollars ($160 today). The small [“T”] hammer is useful for putting strings on, and driving the wrest pins down when loose. It comes at a much lower price than the other”
–From “The Tuners’ Manual,” by Sumner Hill & O. B. Brown, Published in Boston, 1859; page 51.
Sumner & Brown were right about the tuning lever being more accurate: this would have applied to the square, upright, and grand pianos made in the United States in the mid to late 1850s. By this point, any inherent advantage of control, manifest when using a “T” hammer for tuning earlier keyboard instruments, would have been lost because of the inadequate leverage when using same with a mid-19th century American piano.
It should be noted, however, that Montal referred to the Clef Courbée (p.23, 1836; p.29, 1865) in terms of accessibility rather than leverage in his 1836 edition as well as the 1865 edition:
“I also added an extension piece [not pictured] similar to a barrel [to the “T” hammer], with a pressure screw on the side, which is inserted through the sockets between the key and the barrel itself, in order to lengthen the barrel to be able to tune upright pianos without the aid of the curved key [Clef Courbée].”
Montal was describing a longer shaft for the “T” hammer, which would have brought the handle of the tuning hammer closer to the tuner during the process of tuning (with uprights, at least), but it would not have provided the tuner with any more leverage. Perhaps for the purpose of accessibility, Montal used the curved key at angles such as 4 to 3 o’clock, or 8 to 9 o’clock rather than the 10 to 2 o’clock position familiar currently, when tuning pianos.
In G.F. Seivers’ “Il Pianoforte…” published in 1868, Seivers also described the tuning lever (p.147) in terms of overcoming issues of accessibility:
“Atlas Plate 15, fig. 306, for tuning high pianos where the [action] mechanism covers the [tuning] pins, as well as for pianos with the hammers on top, and where the [tuning] pins are under[neath] the keyboard.”
Seivers was recounting obsolete piano types from the 19th century, long discontinued, which had extreme tuning access challenges.

A Stanley No. 984 Ratcheting Joist Brace. Here is another case (in the general toolmaking industry) where a lever has been utilized for the purpose of accessibility; in this example, instead of the traditional, tall bit brace. Such a tool could be used for tightening old foundation sill anchor nuts in a crawl space, for example. Photo from Jim Bode.
Nevertheless, given the proliferation of tuning hammers made in lever form by the 1850s and ’60s, and the increased tuning pin torque of concurrent pianos, it remains clear that leverage was the primary reason for making the transition from “T” hammer to tuning lever.

Very old French tuning lever, with a beautifully turned rosewood handle, similar in shape to the Clef Courbée shown in the 1836 Montal illustration. This one is 9-3/4” long with square socket.
For those who looked carefully at Montal’s plate depicting piano tuning tools you will have noticed an early gooseneck style tuning lever, with a stringing hook added. Also, two of the Universal Tuning Hammers included a lever function: one for oblong tuning pins, featuring a double socket, and the other with a square socket for the more familiar square type tuning pin.
Forty years ago (before children), my wife and I attended “Keynotes: Two Centuries of Piano Design,” an exhibition of 70 pianos from Cristofori to the late 19th century; given at the Metropolitan Museum of Art from 29 May to 29 November, 1985. A booklet written by the Curator Laurence Libin, complemented the exhibition, and this publication was the first time that I had seen Montal’s plate of tools. Unfortunately, Libin did not credit Montal in this publication (although it may have been included in the exhibition itself) so it took me several years to determine the author (pre-internet days).

Early lever Tuning Hammer, as depicted in Giorgio Armellino’s “Kunst des Klavierstimmens.” page 63, 1881 edition, and also in the 1857 edition.
This early lever has similar turnings to my French lever shown above, but lacks nuances in comparison. Or it could just be the limitations of the drawing.
In the 1857 edition of “Kunst des Klavierstimmens” (pp. 42, 43) Armellino extolled the advantages of the tuning lever over the “T” hammer. Interestingly, he explained that the tuning lever had been widely adopted within the tuning practice of France by the 1850s, but less so in Germany, where these books were published:
“…a [lever] tuning hammer, still little used in Germany, but already widely used in France, which has the great advantage that, thanks to its long lever arm, allows a very fine nuance of the tuning pin rotation, whereas with the other [“T” type] hammers, where the hand rests on the axle itself, even the slightest movement makes a rather significant difference, and it is therefore much more difficult to realize the extremely delicate beat ratios demanded by the trained ear, and to avoid excess, which then always necessitates the need to let up and start again. It is therefore advisable for every tuner to equip themselves, in addition to a tuning hammer of the first type, with one of the latter, if possible…”
Another image of this hammer (Fig. 9), or very similar, was shown as part of a tuners’ kit that also displayed piano strings, pincers, music wire slip gauge, tuning fork, and string mutes.

Piano tuners’ basic (very) kit, Fig. 13, p. 66, 1881 edition; Fig. 11, appendix, 1857: “Kunst des Klavierstimmens.”
“These are the most important items that a piano tuner must have at all times in order to be able to deal with all common occurrences. The way in which these items are packed and carried is up to each individual’s discretion; some tuners use a simple canvas bag, others a box, Fig. 13, which is certainly more elegant and also more practical in that it better protects the strings and delicate tools from damage.”

Hexagonal tuning pin socket, allowing 6 positions of the tuning hammer. From “Kunst des Klavierstimmens,” by G. Armellino, 1881, p.63.
In his 1881 edition (p. 63), Armellino described a new development in tuning hammers–the “star” socket. Except this was not the ‘star’ that those of us in the tuning trade recognize as such today:
“More recently, the so-called star hammer has also been used, whose hole is star-shaped, based on the regular hexagon (see Fig. 10) and which fits all tuning pin ratios. It is patented in France and is sourced from Paris.”
Modern star tip/socket, double square broached, which provides 8 positions for the tuning hammer.
Much earlier in his life, Giorgio Armellino wrote “Manuel simplifié de l’accordeur, ou L’art d’accorder les pianos mis à la portée de tout le monde.” Paris : Roret, 1834. Unfortunately, Armellino’s tuning instructions called for perfect fourths, which was a misconception somewhat commonly shared in France at that time. In any case, this book contained some images; one was a plate of piano tuning tools (p. 68), which included two tuning levers:

Plate, or Cut of Piano Tuning Tools in Armellino’s 1834 manual on Piano Tuning, with two Tuning Levers, which predated Montal’s first edition of “L’Art d’accorder” by two years (Montal’s “Abrégé de l’Art d’Accorder soi-même son Piano” published in 1834, did not include a plate of tools).

Copy of some items in Armellino’s plate of tools, from “Abhandlung über Klavier-Saiten-Instrumente” by Christian Friedrich Gottlieb Thon, 1843 (plate 1). Resolution somewhat better in this scan.

English and German music wire gauges, from Abhandlung über Klavier-Saiten-Instrumente by Thon, Christian Friedrich Gottlieb, 1843 (plate 8).
While Thon simply copied a number of images from Armellino, he had some insight into the tools, and spent some time describing them (pp.113, 114):
“A tuning hammer for tapping in or removing the pegs, turning the string loops, and tightening or loosening the strings (Fig. 1. A, B, and C), 4 which must be designed so that its lower opening fits properly into every peg, whether large or small, thick or thin. To this end, the hole for the pegs must be fairly wide at the beginning, but become increasingly narrower as it goes deeper, so that it forms a truncated pyramid with a rectangular base. If the opening is designed so, each peg will penetrate until the space becomes too small for it, and it is thus stuck. At the top end of the tuning hammer is a small hook for turning the string loops, which must be sufficiently strong; because neither the tuning pegs nor the pins for the string loops are usually of the same thickness, and on most instruments, the lower tuning pegs and loop pins have stronger pegs than the upper ones.”
“A tuning leather, also called a wedge (French: coin), is a small piece of leather or felt of the size shown in Fig. 2. A., which is sharpened on both sides up to the end, as shown in Fig. 2. B. It is inserted between the strings of a choir so that only the one to be tuned can be heard, while the others are muted and silent. A stiff sheet of card or folded paper can also be used as a string damper.”
“A tuning fork (French: diapason) for the precise determination of the standard, fundamental, or tuning pitch (Fig. 3). It is a fork-shaped instrument made of good steel, very neatly crafted, whose two limbs or points are square and converge in a handle or stem. Fig. 3, A. shows a German tuning fork; Fig. 3, B. a similar French tuning fork. When using it, one strikes one end of the fork against a solid object and quickly places the lower part of the handle on the soundboard so that the vibration of the fork produces its tone, which is then used as a standard or basis for tuning. Some tuning forks give the A pitch, others the C pitch, and thus one has A and C tuning forks.”

Tuning Hammer with two square sockets, and archaic style chamfered metalwork, appearing similar to that shown with G. Armellino’s 1834 cut of tuning hammers.

Forge welded tuning hammer, lever type, found with early tools in England, probably made by a local blacksmith. The leather wrapping was replaced.

Simple tuning lever, possibly all metal, as pictured in G.F. Seivers’ “Il Pianoforte…” 1868, although some of the tools and techniques in this book hearken back to the era of pre-industrial handwork.

Young woman tuning a piano with a Lever type Tuning Hammer, drawing titled, “Beginning in Earnest,” in “The Girls’ Own Paper,” a London based newspaper devoted to the Victorian women of the time. 23 April, 1887.
By the late 19th century, the tuning lever had gained more acceptance, and was used widely in the United States, but less so in Great Britain: British trade catalogues showed that the “T” hammer was offered in as many variations as the lever hammer right up to the onset of The Great War.

A “Stonehenge” of R. Reynolds “T” Tuning hammers. These Reynolds “T” Hammers are still commonly found in the U.K., in quality piano tuners’ toolkits from the late 19th/early 20th centuries. Combined with the fact that “T” Hammers were offered in British Piano Supply Catalogues in many shapes and sizes into the 1930s, suggests that the “T” Hammer was used for tuning well into the 20th century, but diminishing with the passage of time.
This 1887 article in “The Girls’ Own Paper,” based in London, was focused on encouraging women to consider entering the piano tuning trade. It was authored anonymously by the staff at the paper, and contained a puzzling combination of sound advice, and fallacious opinions. To me, it seemed like one of the staff writers at the newspaper started with some good information, and then elaborated and embellished their own content with it, without having any particular knowledge of the field. Regardless, the article made a particularly strong case for the Tuning Lever over the “T” Hammer:
“[The Tuning Lever with interchangeable heads] is sold by Buck, the tool maker, of Tottenham Court-Road, at about twenty-one shillings. It has two detachable heads, which screw on and off, one head having two holes of oblong shape for English pianos, and another head with a square hole, to fit the tuning pins of foreign pianos. The lever power of this this key is very great… Furnished with this key, the tuner is prepared for every variety of piano made within the last fifty years, can tune with much greater refinement than with a common “T” hammer, and moreover, will do her work with ease instead of hard labour, and in about half the time.” 23 April, 1887, page 2.
“The Girls’ Own Paper” article continued with a condemnation of the “T” Hammer; this strong opinion was undoubtedly shared with many, but not shared by even more. I think this rejection was based on the strained wrists of tuners who used the “T” Hammer on pianos with tight, hard to turn tuning pins, mid-19th century and later.
It should be mentioned, however, that to this day, proponents of the “T” Hammer have advocated for their use in tuning antique pianos. A passage from “Piano World Forums” reflected this position:
“You always see old photos of piano tuners using T hammers to tune oblong pins and like you I must admit I do too, it does make your wrist hurt but gets much better results than a modern crank.” pianobrereton@hotmail.co.uk 22 November, 2008.
Most likely, this wrist strain was due to using the “T” Hammer on a late 19th century piano, with wrest pins tighter than early 19th century pianos, but still with less torque than tuners generally encounter today with modern pianos.
Universal Tuning Hammer Sets

Marque Accorda Universal Tuning Hammer (France): where the concept of ‘multi-tool’ would be taken to the next level! From c. 1840 to 1940, extensive tuning sets such as these would be made, sold and used in Germany, France, England, and the United States. And used by Tuners in colonial territories and many other places.

Marque Accorda Tuning Hammer in lever mode. A screwdriver was stored within the nickel plated steel handle

Leon Pinet, Paris: Universal tuning hammer. From “The Practical Manual for the Piano and Harmonium Tuner,” Nugues, Pouget, and Martin.

Victorian-styled universal tuning hammer, from England. This was carried in J. & J. Goddard’s trade lists for many years.

Top: Heavy Victorian Universal Tuning Hammer; Bottom: Weygandt & Klein, Stuttgart. The Univeral Tuning Hammer reflected the ambivalence many Tuners of the time may have felt regarding which type of Tuning Hammer to use. Realistically, the Universal Hammer offered the Tuner greater flexibility and versatility than was possible before.

As the 19th century progressed, pianos became larger, heavier, with greater string tension, and some of the tools grew in size as well. Ferrules in German silver.
Tuning pins of the 19th century square piano were situated in the back of the case, which means the tuner is required to bend over most of the width of the instrument in order to reach the tuning pins. Long extensions of the tuning hammer helped make this less challenging. Shown below is another universal tuning hammer, which can be used either as a “T” hammer or as a long (16″) tuning lever.

This photo includes both the “T” tube as well as the lever extension for demonstration purposes. Attachments are used separately.
Since the square (and other early pianos) had oblong tuning pins, there are only two tuning positions available. The tuning head with two sockets at 90 degrees made four positions possible. This was called the double oblong head. Even so, the room to work was limited, so some of the tuning would be done with the “T” hammer, which offered little leverage but enabled the tuner to work within a confined area of the piano.

Steinway Square Piano, interior view, with tuning pins near the back of the case. Image from Wikipedia Commons.

Even a saw was included for the tuner. Hammacher Schlemmer: square, oblong, and extractor sockets; Alfred Dolge oblong socket.

Otto Bergman, Berlin Universal Tuning Hammer, and action wire bending tool with “T” handle, c. 1927.
Extension Tuning Hammers
Extendible tuning levers became popular. Even though this feature was originally intended for the square piano, levers with this feature are still commonly available. This is a very light and small lever, which has an extendible shaft almost as long as the handle itself. This example has a brass collar and a round thumbscrew.
Here is an attractive double head extension tuning hammer, not with oblong sockets, but with two square sockets. It predated the introduction of the star socket, so dates from before 1870. The rosewood handle incorporates some sapwood, and the ferrule is bimetal, brass (copper and zinc) and bronze (copper and tin). Most double tuning heads were made with two oblong sockets; a few were made with one square socket and one oblong socket, and some were like this one, two square sockets. The square sockets were designed to give the tuner a leveraged position at every 45 degrees. This hammer has a subtle flat area behind the ferrule, in order to facilitate a quick flipping action of the hammer when changing sockets.
The extension hammer was introduced around 1860, although there was no single inventor for this feature. Napoleon Erlandsen brought his extension Tuning Hammer to market in 1863; it was his professional version that influenced standard trade practice the most and more can be read about the Erlandsens in subsequent pages on this website.
Below are three tuning hammers with set screws and detailed steel ferrules, with bead type patterns similar to those of the old C. H. Lang machine shop in Chicago. The hammer on the top has a tip marked American Felt Co., and the middle hammer, has an extremely short C. H. Lang, Chicago tip. The hammer at the bottom was sold by Tuners’ Supply Co. and Tonk Bros. All three hammers have replacement handles which I turned on a lathe and then bored out (not unlike a woodwind instrument) for the internal tube with the extendible shaft inside. The top two are made with Indian rosewood, and the bottom one is made from brown ebony.
These hammers all had badly cracked original handles. The hammer at the bottom shows the typical diameter of the internal tube within any quality extension lever. With the beaded extension shaft housing exposed, you can see how large the diameter actually is. The degree to which hardwood extension handles are bored out is considerable, and any slight contraction of the wood dimensionally can lead to a cracked handle. This is why ~15% of these handles have a split, anywhere from 5 to 150 years later. And it also makes the extension tuning hammer considerably more difficult to produce than fixed models. –Which I’ve experienced, having fitted a number of new handles to antique examples which had badly split wood.

Beaded extension tuning hammer, from 1940 Hale catalogue, with the same hardware as the hammer at the bottom of the previous photo.

Extension hammer, with exposed beaded extension tube. Tonk Bros. Piano Supply Division Catalogue, 1934. From collection of David Abdalian, RPT.
Some of the hammers below were made in a somewhat ornate, or Victorian style. The shafts of these hammers have a taper, sometimes to a very small diameter, compared to those made in the 20th century. Tuning pin torque (tuning pin tightness in the pinblock) in these 19th century instruments was significantly less than the relatively high torque which is common today, even when these pianos were new. Two hammers, both by the same maker, are shown in the next two photos:

Ornate Victorian Tuning lever Hammer, with detachable heads. Both from same maker. Note the 20 degree head of the lower hammer. In actuality, 20 degrees denotes in excess of 90 degrees, so the total angle of the head in relation to the shaft is 110 degrees. From the beginning of tuning levers, even with the fixed gooseneck hammers in the 1830s, this angle became a matter of individual preference for the Tuner, and a variety of head angles and lengths can be found, that were made in response to this demand.
Generally, tuning heads of this period are not interchangeable with those of other makers, and may not be so with various time periods of the same maker’s output. This hammer has fitting numbers, like many tools of this period:

Cut of Piano Tuning Hammers, from The Tuner’s Manual, by Sumner Hill & O. B. Brown, Published in Boston, 1859.
These hammers are very similar to the Victorian hammers photographed above. In the United States, by c. 1859, the long handled tuning hammers were preferred for tuning. In England, the “T” hammer would continue to be used predominantly for tuning until the WWI era.
The screw thread that connects the shaft to the head was traditionally straight and not tapered, and often included a friction mating surface of various sizes when the head and shaft are screwed together. This differs from the 1/8″ tapered pipe thread, familiar today, that Hale (Tuners Supply Company, Boston) introduced, c. 1925. Here are three examples—top, octagonal shaft; middle, hexagonal (both same maker); and bottom, square shaped shaft, H. S. and Co.

Top, octagonal shaft; middle, hexagonal (both same maker); and bottom, square shaped shaft, H. S. and Co., N.Y.
Here is a more recent photo of the two unmarked Extension Tuning hammers made by the same maker. I plated the ferrule and thumbscrew of the double barrel hammer in nickel myself (after frustration in hunting for metal platers who are willing to work on personal items). Also, this was a case where the metal ferrule could not be separated from the rosewood handle.
The hammer shown at the top was found in northern Maine near the New Brunswick border, in the 1970s. The hammer at the bottom was found around 2010 south of San Diego, close to the border with Baja California.
Chickering pianos were often considered the American piano industry leader until the 1870s, earning the endorsements of many virtuosi of the day, including Franz Liszt.
Alternative Tuning Hardware: a brief glimpse
When Mason & Hamlin in Boston decided to add pianos to their established production of harmoniums in 1883, they introduced a new design of tuning hardware known as the “screw stringer.” In their pianos, the screw stringer design eliminated the pinblock with tuning pins, which has been the established standard since the beginning of stringed keyboard instruments to the present day. It was an attempt to eliminate the tuner’s challenging task of manipulating the tuning pin with its inherent twisting and bending while tuning. The screw stringer did achieve this goal, but did not resolve issues surrounding rendering the string through its termination points: the pressure bar and bridges. This design was partially successful, and it is still possible to tune some of these old screw stringers.
This is a tuning key made by Mason & Hamlin for tuning the screw stringer. It was included inside every new Mason & Hamlin upright piano. It has a star socket to provide eight tuning positions. It also has a long stem so that the turning handle could clear the case, which was helpful for both uprights as well as grands. This tool came from the Hornung estate in 1990:
Mason Hamlin’s Piano Stringer; Patented July 24th, 1883; TO TUNERS, Always tune with UPWARD MOVEMENT of the screw. When a string is too sharp, drop it below the desired pitch and draw it up again, as the tendency of the string in these pianos is to sharp, not to flat, under a test blow. INTERNATIONAL PITCH, A 435 Adopted Nov. 6, 1891.

Mason Hamlin Screw Stringing tool removed from piano by tool collectors. Martin Donnelly Auctions 2023.
It is not OK to remove these hammers from either a serviceable or restorable instrument.
Other similar alternative tuning hardware was developed concurrently by Brinsmead (the “Top Tuner” ) in England and, to a very limited extent, Ivers and Pond, also in Boston. Mason & Hamlin continued production of the screw stringer until as late as 1905.

Wurlitzer advertisement for the “Uniplate” construction, from “Exporters’ and Importers’ Journal, 17 February, 1928; p. 7.
Additional alternative tuning arrangements included the tuning pins fastened directly into the iron piano plate instead of into a wood pinblock, which did not require proprietary tuning tools. Examples of this tuning arrangement include the Wegman “Tuning Pin Fastener” (c. 1890–95, Auburn, NY), Wurlitzer “Uniplate” (c. 1926, North Tonawanda, NY), and the “Beale-Vader Tuning System” (c. 1902, Sydney Australia). Broadwood and Sons, in London, introduced “The Threaded Wrest Pin” c. 1862, where the pin is threaded into the tapped holes of the metal plate above a threaded friction fit into a more traditional wrestplank underneath the plate. Fortunately, these pianos included a warning sign for the tuner about this!
John Henry Papps, and Son (Louis Franks) Pianomakers in Southsea, U.K. invented “The Stronghold Frame,” patented 27 May, 1897 in England; 16 August, 1898 in the U.S.A. Being situated at the major port at Southsea, J.H. Papps would have observed many ships coming and going in his town. As a Pianomaker, Papps would have received a lot of feedback about the problems of keeping pianos in tune while being used on a ship. In response, Papps developed his stronghold frame which eliminated the wooden wrestplank, and replaced it with an iron pin holding unit. Papps’ invention met with moderate success, and his pianos were used on U.K. Naval personnel transport ships, and cruise ships. These pianos still had traditional soundboards, that reacted to changes in humidity, however. Papps and Son would continue to manufacture pianos through the early post WWII period at 382-384 Commercial Road, Landport.
Papps & Son today is best known for their tweezer mute, patented in 1886, invented to negotiate the challenging obstructions of the upright overdamper (“birdcage” in North America) action of the Victorian era. It is still in common use today, and is mass produced in the U.K. as well as China. Also J.H. & L.F. Papps patented a “Centre Pin Easing Pliers,” in 1912.

This is an unusual tuning lever style, with only a few examples which appear to date from the 1860s or 1870s.
Here is a fairly similarly shaped design to the lever above–it was found among the US patents. It has the same basic shape as the preceding tool, with a metal cap, or striker, at the end of the handle, and a long metal sheath at the business end. There is no shaft and the head is directly attached to the heavy ferrule at the front of the handle.
This patent is for a rotating square socket with a clutch feature that allows for many tuning positions more than the four possible with a fixed square socket. A star shaped socket became fairly available no more than ten years after this patent. Nevertheless, designs for a rotating ratchet-like square socket can be seen in the US patents as late as the WWI era.

Ratchet/revolving head type tuning hammer, sold by J.&J. Goddard Piano 68 Tottenham Court Road (catalogue c. 1946-1949), London. This Tuning Hammer was marketed to sight impaired piano tuners in the years immediately following WWII.

Tuning hammer heads offered in the 1885 Hammacher Schlemmer Piano Supply Catalogue. One of the earlier appearances of the star (double square) socket. A star tuning socket can also be seen in an early 1885 Hale patent. The star tip made eight tuning positions available with the square tuning pin.
‘Gooseneck’ Tuning Hammers

“Stimmhammer,” or German hammer; the beech handle will accept modern Renner type stems. This example, marked “Germany,” was probably made between the 1900s to the ’20s. The rosewood hammer has “STEEL” marked on the shaft and has an oblong socket. It was made by Richard Reynolds of 4 Upper Rathbone Place in London. Reynolds was the most prominent maker of specialized piano tools in England in the late 19th/early 20th centuries. More can be found on Reynolds here.

Gooseneck Tuning Hammer, as it appeared in the American Felt Co. catalogues for 1900 and 1911, and The American Piano Supply Co. catalogue of c. 1925 (before takeover by Hammacher Schlemmer in 1927).

From Otto Bergman, Berlin, Tool Catalogue, section for pianomakers, c. 1927: 21 and 22. Tuning hammer, with long and short inserts for changing. 23. Hammer punch. 24. Set screws. 25. Tuning hammer with star socket. 26. Tuning hammer with Adjustable angle for head. 27. Tuning hammer with square socket. 28. Circular floor cutter. 29. Drill bit with perimeter and center cutting.

“Bluthner pattern” tuning hammer, made by Weygandt & Klein of Stuttgart, Germany. Characteristics include the bend in the shaft directly above the tuning pin tip, and a thickening of the shaft diameter
Curved shafts, known as a “gooseneck shaft” in North America, were used extensively in England, Germany, and France. Hammers with this feature are considered student models at best in North America, but were used in the past for some serious tuning in Europe. The piano industry in Continental Europe and Great Britain primarily utilized various species of beechwood for their piano wrestplanks as well as some other general structural components. Traditionally built wrestplanks made of beech, typically yielded significantly lower tuning pin torque than the hard rock maple sourced from America. American piano makers universally used layers of hard rock maple for their pinblocks, which could potentially yield a tuning pin torque as much as 150 inch pounds. Hard rock maple has a higher performance under compression than beech–from the driven tuning pin. European tuners and stringers did not need the extra leverage and robustly constructed tuning hammers that the Americans required.

Top to Bottom: J.& J. Goddard, walnut handle, 68 Tottenham Court Road, London (Richard Reynolds); R. Reynolds, Cuban mahogany handle; H.J. Fletcher, London, rosewood handle, German (unmarked), beech handle; Weygandt und Klein, Stuttgart, rosewood handle; German (unmarked), pear handle, which is probably the oldest hammer in this photo by far; American (unmarked) London pattern handle in rosewood.
This Renner tuning hammer has the short-headed stem, set at more than 20 degrees. Hale had a 20 degree head as well, and it was marked as such. I had a 20 degree Hale head, but sold it off years ago, as the 20 degree angle did not work for me. This particular 20 degree stem belonged to Johannes Warger, a San Francisco based Dutch-American tuner who passed away in 1986.

A. Dolge Gooseneck Tuning Hammer. Coming from Germany, Alfred Dolge would have been comfortable thinking of this Gooseneck Hammer as ‘1st Quality.’