When you think about the sheer number of strings in a piano – multiples per meaningful, remember – and the tension to which they are stretched, you realize that there must be a colossal amount of force trying to break the piano in two. This explains the need for such heavy construction – a frame of cast iron is needed just to resist the tension of the strings. It also explains why a specialized piano tuner can be an important person to call if you need piano tuning.
It is tempting to compare tuning a piano to car maintenance – you can do it yourself, but you may feel more comfortable putting the risk in the hands of an expert. However, the situation is already more important than that, as the time of action of tuning a piano is far more complicate and takes far more patience than most ordinary means servicing. Changing the oil or the spark plugs is nowhere near as involved as tuning two hundred or more high-tension wires.
Attempting to tune a piano yourself is certainly possible, but there is a range of knowledge and skills that only an experienced specialized will have. One aspect of this is in understanding the current condition of the piano. Since you are reading this article, you may have a piano that has sat around without maintenance for quite some time, and the cost of specialized piano tuning seems prohibitive. However, it is precisely this kind of piano that can be dangerous, as a neglected frame may have started to develop ineffective spots that increase the risk of the complete structure collapsing violently in on itself. You would not want to have your hand inside a piano when this happened. An expert piano tuner can recognize the danger signs much more freely than you will be able to.
Having said that, if a piano technician has confirmed that your instrument is in good shape, you can certainly begin learning about piano tuning yourself. If nothing else, it takes patience. It can be very easy to give up part of the way by tuning and ruin the whole course of action. There are also various skills that must be picked up along the way, such as the piano tuners’ method of setting the pins in such a way as to promote tuning longevity and prevent the piano from sounding sour for as long as possible. Piano tuning certainly takes effort, but it can also be a rewarding course of action, and maybe already therapeutic.