How could the lifespan of the handpan instrument be affected by rust?
The handpan is a music instrument made from two half-shells glued together. Usually, those shells are produced from sheet steel. One of the problems that naturally come with the use of steel is corrosion, reducing the lifespan of the instrument especially if the instrument is improperly cared for. This short article will discuss the phenomenon of rust, a special type of corrosion.
Corrosion is the process by which metals are slowly broken down through chemical reactions with substances in their environment. One special case of corrosion is rusting, meaning a redox reaction involving oxygen and water from the environment with the iron contained in the steel.
So what happens on element level? We want to explain this a bit more chemically:
First, solid iron (Fe) dissolves in water producing iron ions (Fe2+) and electrons (e–). Those electrons react with oxygen (O2) and water (H2O) from the environment and form hydroxide ions (OH–). The iron ions, which can be denoted as iron(II), react further with Oxygen (O2) from the environment to form another type of iron ions (Fe3+), denoted as iron(III), and oxygen ions (O2-). This results in a solution containing iron(II), iron(III) and water. Next, both iron(II) and iron(III) react with water (H2O) to form different forms of rust (Fe(OH)x) and hydrogen ions (H+). Finally, those hydrogen ions (H+) react with the hydroxide ions (OH–) initially produced from water forming water (H2O) once again. The result of this reaction is a red or an orange-colored surface which is highly fragile and porous.
One way to prevent the corrosion in the handpan is by using an alloy such as Ferrochrome FeCr. Stainless steel can also prevent rust almost completely. It is important to know that changing the composition of the steel also affects the sound and the appearance of the instrument. Another way to prevent rust is by adding a step to the fabrication known as gas nitriding by which the handpan material undergoes a heat treatment. This process makes the material more rust-resistant but does not guarantee complete prevention of the phenomenon.
After the fabrication, the surface of the instrument should be kept clean and dry. Keep in mind, that the edges around the polished surfaces are very sensitive towards rust. After each playing session, the player must clean the handpan with a soft, clean, dry cloth, preferably microfiber. This is important because sweat from the hands can deposit salts onto the surface, which will accelerate the formation of rust. Another technique to slow down rust is to add a protective layer, by applying liquid ceramics (TurtleCare).
<We do not recommend using oil to treat your instrument. Instead of staying on the surface, oil moves into the metal, there is no protective layer and also it changes the sound of the instrument, reducing the overtones in a long term.>
This way, the moisture will not react with the iron in the metal. Another important aspect is the environment in which the handpan is stored. A proper storing requires a low-moisture or temperature- and humidity-controlled area. Such requirements can be fulfilled by using a wall mount, this is the best way to keep your instrument rustproof.
In conclusion the best way to prevent rust is to keep the instrument away from moisture. Water reacts with iron to form rust. Thus, an environment with no moisture will not create rust. It is very important to remove the sweat from the surface of the instrument, apply a protective coating and store the instrument away from humid environments. Although there is a wide selection of materials for the fabrication of the handpan, which are highly resistant to rust, there are other aspects to consider. The material choice is not only determined by the resistance against rust, but also the resulting sound and the appearance of the instrument.