How To Repair A Piano String

How To Repair A Piano String

In today’s article, we will talk about piano strings, how they are, what their characteristics are and what particularities they have. This turns out to be an introductory topic in the knowledge of this instrument that can help music lovers, teachers, and piano technicians. In principle, contemporary pianos, both vertical and grand, have a system of string scale design called “cross-string”. 

The ones stated in black we call bordonas or bordones, and the ones represented in green color that receive the name of flat or steel strings. On any piano it crosses these strings in such a way that the flat strings are at a lower level. Compared to the strings it can cross them.

Crossed String Pianos

This cross-string design is not ancient in the piano’s history but has more or less one hundred and fifty years of evolution. All pianos had all straight strings at the same height and there was no crosslinking. This design favors the vibration by sympathy of the sound of the strings. Especially when playing multiple notes through chords or when pressing the sustain pedal.

How To Repair A Piano String

Some strings, when you remove the dampers resting on them (ie when you press the sustain pedal and leave them with the possibility of vibrating). Even if you do not touch their corresponding key their harmonics tend to vibrate out of sympathy. Simply to play some other note of the piano whose fundamental frequency coincides with the harmonic of that note you want to vibrate.

The result of this is a much richer sound. As the duplex scales, the sound of the piano gains a great richness. Because, beyond the strings that are vibrating by the notes that are being played. If we keep the sustain pedal pressed there will be other strings vibrating in certain harmonics although not played by the phenomenon known as vibration by sympathy.

The cross-string design favors this vibration by sympathy greatly enriching the sound of the piano. It is also one of the reasons why electronic pianos, however expensive they may be, will never sound the same as an acoustic piano. Since they do not have strings, they cannot generate this phenomenon of vibration by sympathy and they cannot generate it because it is something that cannot be electronically.

Piano String Types

As for the strings, we have already mentioned two large groups: flat strings and strings. It makes the former of a special steel alloy that also meets certain quality standards in terms of thickness uniformity, vibratory properties and so on.

Bordeaux strings are also steel strings, but they also have a copper wire wound, thinner. Which covers much of their primary useful length (the main vibrating part of this string). This copper covering achieves lower frequencies with no string to be too long, which would make it difficult to build pianos.

For example, if in a grand piano the strings have no coiled copper. To have the same frequency that they should simply have with the steel. That constitutes the length of those strings should be double or triple the normal length of the piano.

This would make the instrument in question also double or triple in length and this would increase its production and selling costs. And complicate its transfer and its location in concert halls, much less in a house or apartment.

Many times, in some pianos, the sound generated by the strings by this copper wire that covers them includes a certain snore. That is the price for us to have pianos of reasonable sizes.

Piano String Thickness

As for flat ropes, if you are not an expert in the matter and you look at them with the naked eye. You might think that they all have the same thickness. However, this is not true; every four or five notes the thickness of the string changes very slightly, which can mean that an average piano has between fifteen and twenty different thicknesses for flat strings.

Piano String Splice

The thickness of the central steel core and the copper wire also varies in the bordona strings. Even the latter can make two turns on the steel core, i.e. make a whole winding on the rope. And again winding on the previous winding to get a much lower frequency, a lower sound. This is especially true in the lower part of the piano.

This detail of the measurements of the thickness of the strings must be We must take this detail of the measurements of the thickness of the strings when replacing them. Replacing each string using a piano tuning wrench or a specialized tool with a suitable thickness and this by first measuring it with a caliber. Flat strings usually come in rolls of piano wire steel wire and separated by thickness.

Professional piano technicians have several rolls, as many as there are thicknesses of flat strings. And at the moment of changing a string they simply measure with a caliber cutting the string. Take the roll corresponding to that measure, measure the length of the string on the wire, cut it with a pliers and then place it making the knots.

Types Of Piano Strings

This procedure differs the strings bordonas because there are no rolls of this type of strings. But on every piano, on every note, the strings are different not only the total length of the string but also the coiled copper segment. This means that for each broken strings of each particular piano, it must make a custom replacement and they can do this immediately.

Piano String Repair

A professional technician should measure the thickness of the steel, the length of the rope, the length covered by the copper. The thickness of the copper wire and note whether it has one or two turns of copper wire. Then with a special artifact that some luthiers usually have. We assemble the string and then replaced on the piano.

I should also note that although it is an art to assemble a string. Many times it does not sound the same as the rest of the piano’s strings. Even though this new string complies with all the measures and specifications of the main string.

This usually generates some sound problems, if it recommends the cut bordona string belonged to change both. Even not cut, to minimize possible sound differences.

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