Cleaning Copper Wound Strings Over a period of time the copper wound strings on a piano develop a dead tone. Impurities lodge between the windings which cause the strings to lose their flexibility. The normally bright coloured copper gradually turns black, which comes off in a form of powder similar to soot, when touched. In certain Rotorua areas, where sulphur is a product of the local geothermal activity, the reaction from the sulphur can affect the strings so badly, the bass section becomes unplayable. When a bass string is removed from a piano, it can be so stiff, it can be held upright without any bending whatsoever! I have had to rescue many pianos from this fate, and their are two options open to the customer. Firstly the affected strings can be replaced by a new set, which is what I would normally recommend but is the most expensive. Alternatively the strings can be restored by cleaning and then replaced. The former method is a fairly straightforward procedure which is covered in many manuals. The restoration option however is not so straightforward and it is the purpose of this paper to explain how it is done. If the piano is to remain in a particularly bad sulphur area then it may make better economic sense to clean rather than replace the existing strings as they will be back to the same condition within five years (even with new ones). The options are first given to the customer. If they choose