Bradford system
Encyclopedia
The Bradford system is a way to assess the quality of wool
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To measure the fineness of sheep wool
fiber before microscopes and lasers were so used, English wool handlers in the city of Bradford
described wool by estimating (with experienced eyes) how many 560-yard hanks of single strand yarn could be made by a good spinner from a pound of "top." (Top is cleaned combed wool with the fibers all parallel) The finer the average diameter of a single wool fiber, the more hanks could be spun. From a pound of "64s," for example, sixty-four such hanks could be made (more than 20 miles!). From the finest wools, more than 80 hanks could be spun; from the strongest, perhaps 36 or fewer. Using ranges denoted by the stronger end (that is “44s” ran up to “46s”) wool lots were classified and prices derived.
The Bradford count may be biased no matter how experienced the rater is; also it relies heavily on number of crimps (regular undulations) per inch, which has a not-very-strong correlation with actual average fiber diameter.
More objective measuring systems are rapidly replacing its use in the international market, though it is still widely used among shepherds and breed associations. The United States Department of Agriculture in 1966 issued official standards (for the U.S.A. only, not applicable worldwide) which assigned ranges of average fiber diameter (AFD) and maximum standard deviation to each of the Bradford counts. For example, wool with average fiber diameter in micrometers from 27.85 to 29.29 was to be called "54s."
In the last ten years, objective measurement of several fiber characteristics has become faster and more available and is likely to replace the Bradford count system in all commercial arenas. The spinning count, with all its lore, will not disappear overnight.
Average fiber diameter, although a salient characteristic of sheep breeds and the major determinant of end-uses for wool, is only one of many factors that determines wool quality. For a good discussion of wool classing
see Wool Grading, a 1996 article by Rodney Kott of Montana State University
.
Wool
Wool is the textile fiber obtained from sheep and certain other animals, including cashmere from goats, mohair from goats, qiviut from muskoxen, vicuña, alpaca, camel from animals in the camel family, and angora from rabbits....
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To measure the fineness of sheep wool
Wool
Wool is the textile fiber obtained from sheep and certain other animals, including cashmere from goats, mohair from goats, qiviut from muskoxen, vicuña, alpaca, camel from animals in the camel family, and angora from rabbits....
fiber before microscopes and lasers were so used, English wool handlers in the city of Bradford
Bradford
Bradford lies at the heart of the City of Bradford, a metropolitan borough of West Yorkshire, in Northern England. It is situated in the foothills of the Pennines, west of Leeds, and northwest of Wakefield. Bradford became a municipal borough in 1847, and received its charter as a city in 1897...
described wool by estimating (with experienced eyes) how many 560-yard hanks of single strand yarn could be made by a good spinner from a pound of "top." (Top is cleaned combed wool with the fibers all parallel) The finer the average diameter of a single wool fiber, the more hanks could be spun. From a pound of "64s," for example, sixty-four such hanks could be made (more than 20 miles!). From the finest wools, more than 80 hanks could be spun; from the strongest, perhaps 36 or fewer. Using ranges denoted by the stronger end (that is “44s” ran up to “46s”) wool lots were classified and prices derived.
The Bradford count may be biased no matter how experienced the rater is; also it relies heavily on number of crimps (regular undulations) per inch, which has a not-very-strong correlation with actual average fiber diameter.
More objective measuring systems are rapidly replacing its use in the international market, though it is still widely used among shepherds and breed associations. The United States Department of Agriculture in 1966 issued official standards (for the U.S.A. only, not applicable worldwide) which assigned ranges of average fiber diameter (AFD) and maximum standard deviation to each of the Bradford counts. For example, wool with average fiber diameter in micrometers from 27.85 to 29.29 was to be called "54s."
In the last ten years, objective measurement of several fiber characteristics has become faster and more available and is likely to replace the Bradford count system in all commercial arenas. The spinning count, with all its lore, will not disappear overnight.
Average fiber diameter, although a salient characteristic of sheep breeds and the major determinant of end-uses for wool, is only one of many factors that determines wool quality. For a good discussion of wool classing
Wool classing
Wool classing is an occupation for which people are trained to produce uniform, predictable, low risk lines of wool. This is carried out by examining the characteristics of the wool in its raw state. The characteristics which a wool classer would examine are:Breed of the sheep: Shedding breeds will...
see Wool Grading, a 1996 article by Rodney Kott of Montana State University
Montana State University - Bozeman
Montana State University – Bozeman is a public university located in Bozeman, Montana. It is the state's land-grant university and primary campus in the Montana State University System, which is part of the Montana University System...
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