Piano Agraffe Breakage
What Is an Agraffe?
An agraffe is a solid brass piano component made up of a head and a threaded stem (see fig. 1). Positioned in front of the piano’s tuning pins, agraffes are typically present only in the bass and tenor sections of pianos, with one agraffe per note. As such, most pianos have around 50 agraffes. Each agraffe head contains beveled string holes, the number of which corresponds to the number of strings installed for the respective note. This design creates a sharp termination point for the strings, allowing them to vibrate properly.
Fig. 1 monochord, bichord, and trichord agraffes, respectively.
Fig. 2 visual representation of one string in the piano demonstrating location of agraffe
Agraffe Breakage
Agraffe breakage can happen at any time, although it most often occurs while the piano is being played or tuned. Breaks are not the fault of the pianist or tuner.
Agraffes usually break at the point where the stem meets the head. If the brass in this area becomes compromised, the force of the string(s) pulling against the agraffe can cause it to abruptly break in two, accompanied by an abrupt, loud noise. Once an agraffe has broken, the note will produce a “thuddy” dead tone when the key is struck. Until the agraffe
is replaced, the corresponding note will be unplayable.
While there are no preventative measures that can keep a piano’s existing agraffes from breaking, if a piano is to be rebuilt or restrung, it is crucial that original agraffes are replaced to reduce the risk of potential future breakage. This is particularly important when the specific make, model, or era of piano is known for breaking agraffes, or the piano shows signs of previously replaced agraffes.
A broken trichord agraffe with a separated head and stem.
Agraffe breakage typically occurs for one of the following reasons:
Poor Agraffe Design
During certain eras, some piano manufacturers designed agraffes poorly, with stems not threaded all the way up to the base of the head, or too sharp an angle between the stem and head. These inferior designs created a predisposition for agraffe breakage over time.
Improper Installation
Occasionally, agraffes are overturned during installation to achieve proper alignment with strings. Overturning compromises the brass where the stem meets the head, which can lead to agraffe breakage, sometimes many decades later.
Cats or Rodents
Cat or rodent urine on agraffes can cause oxidation and compromise their structural integrity.
Agraffe Replacement
The only solution for a broken agraffe is to replace it. Agraffe replacement involves extracting the broken agraffe stem from the cast-iron plate, installing a new agraffe and then re-stringing the note. If your piano has a broken agraffe, contact Brad Fant Piano Service to schedule the necessary repairs.
A broken trichord agraffe before repair (left) and a replacement trichord agraffe installed (right).
