At 8:48 pm -0700 2/8/07, David Love wrote: >...While I can't say I understand the mechanics of twisting I do >wonder whether it's a compensation of some sort or whether the >twisting happens during the wrapping process with some makers and >not with others. ÊAnyway, all you string making experts, please >enlighten me. As you say, it should not be necessary to twist the string in order for it to sound good, but it is a good idea to give it a turn or two to restore the tension in the copper that is applied by the maker while the string is clamped in the machine. When the string is removed from the machine the tension in the copper puts a twist in the steel until it is insufficient to overcome the resistance of the steel to twisting. When you twist the string on installation you are at least restoring the tension in the copper that was lost when the string was removed from the machine. It would be possible for a stringmaker to twist the steel before winding on the cover and advertise his strings as "pre-twisted", but this is an extra and unnecessary chore, since educated repairers know that it is good practice to twist on installation and have control over how may twists to apply. I personally give two whole turns to bichords in most circumstances, which results in the cover being tightened round the steel to a greater degree than it was before removal from the machine. I have never made a scientific comparison but I have the distinct impression, which I think most restringers will have discovered, that a brighter tone results in the long run. To give an example : the stringmaker is covering a No. 16 core with copper 0.4 mm in diameter. He applies as much tension to the copper as is possible without the copper breaking, and this degree of tension is learned through experience. Since the copper remains elastic to a degree once it is wound round the steel it is acting as a coil spring striving to lose its tension by twisting the steel, and when the stringmaker releases the steel from the chuck he will feel the wire twist a certain amount as the copper pulls. Now the maximum tension the stringmaker can apply to copper wire only 0.4 mm in diameter without its breaking is not necessarily the tension that will give the very best tone and experience suggests that an increase in the tension of the copper achieved by twisting on installation has a beneficial effect. All that said, a set of bass strings should sound good and even, even if the stringer neglects to twist the strings, and if a string sounds dull or dead, it is because the stringmaker has not pulled hard enough on the copper when making the string. The work of a new stringmaker needs to be carefully monitored by measuring the diameters resulting from his work. If the diameters are larger than expected, he has not been pulling hard enough and the cover is not as tight as it should be; the string will not sound as good as it should and might sound dull or even buzz or rattle. A new stringmaker needs to learn fast if he's not going to cost the firm a fortune in wasted copper and rejected strings. Some people never learn and I am certain that some firms have no standard test to monitor their work and regularly supply uneven sets of strings or sets that contain dull or buzzing strings. JD
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