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Abstract
Two greasy-wool bulks were made up from sound fleeces selected from a single medium-merino flock so that their mean diameters, mean staple lengths, and mean crimp frequencies would be the same or similar, but the coefficients of variation of diameter (V d) would be different. The tops made from these bulks showed closely similar mean fibre diameters (20·6 and 20·8 (μm), lengths, and length variabilities, with the V d values 18·3% (L) and 21·4% (H). In conventional Bradford spinning, L was slightly favoured over H at the spinning limit, but the differences in ends-down per 100 spindle-hours at commercial counts were negligible. Yarn properties, such as tensile strength and elongation at break, and yarn evenness did not disclose differences of any consequence. Fabrics made from 25-tex yarns gave closely similar properties. Ambler Superdraft spinning supported these conclusions.
The difference of 3% in V d values did not indicate significant worsted-manufacturing differences between the tops. Since these tops were made from single-quality sources, the V d values are low compared with the range of values for European tops of the same diameter, the majority of which would occur in the 20–26% V d range.
