Denzil Wraight - Italian Keyboard Instruments |
Sizes of Nuremberg Wire
(N.B. This table prints best with Internet Explorer)
The above list is a simplified version of Table 4 from my article, 'Principles and Practice in Stringing Italian Keyboard Instruments', Early Keyboard Journal 18 (2000), 175-238. The sizes have been derived from four sources: from measured, identified Nuremberg wire; wire measured by Lüdicke in 1781 (which is thought to be of Nuremberg origin); data given by Hachette in 1824; and data from Thomée in 1866. My hypothesis is that wire of the sizes 1-5/0 was drawn with a different drawing ratio than the wire for sizes 1-12. The latter sizes were drawn in finer steps in order to make the drawing easier with the method used and in order reduce breakages.
The first two columns show the Nuremberg gauge numbers and the sizes I have inferred. The 3rd column shows standard sizes available from Malcolm Rose which correspond to, or are very close to the Nuremberg sizes (+/- 0.01 mm). The 4th column shows the special sizes Malcolm Rose also makes ( wire sizes to special order ) if it is desired to match the Nuremberg sizes more closely. The 5th column shows the numbers I have given to Malcolm Rose's wire based on Nuremberg wire sizes. The last three columns are intended as an aid to making your own checklist of sizes you have, or wish to order, for (respectively) iron, yellow brass, and red brass.
Although the Nuremberg wire drawers did not work by measuring diameter (but instead the wire extension) the sizes could have been, and indeed appear to have been held within close tolerances, e.g. about +/- half a gauge, by this method. 2/0 was sometimes written as 00 and 3/0 as 000.
These sizes can be used for many instruments, especially French and German, where gauge numbers are known, although not all wire gauge number markings will have been for Nuremberg wire. A comprehensive list of gauge numbers found on Italian instruments is given in my article cited above.
In practice some of Malcolm Rose's standard sizes can be used instead of special sizes, i.e. 0.65 mm for 0.63 mm = 2/0.