> Normally as you add tension that's all you do, and if the tension is > released the wire regains it's former shape and size. Good response Conrad. There is one further issue not normally covered. When pulled to pitch a strings gives up about 95% of it's stretchability in the first five minutes of tension. The rest occurs over a period of about five years and acquires a permanent deformation called "CREEP". It is creep that causes a string to go out of tune when it is new. It reaches a point of equilibrium with the tension after the five years and will not stretch further unless pulled to a higher tension. Creep is a calculable quantity but for our needs tension and breaking % show us how much creep can occur. That is why bridge makers have turnbuckles attached to the vertical support cables. They have to be turned to keep the roadway level. Same principal in piano wire. Newton
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