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The article discusses the possible use of the new automatic feed grip of the Almeter apparatus to test the internal structure of worsted slivers. One of the authors used the Almeter automatic grip, then at the design stage, for analysis of the variation of fibre-length distribution along a sliver. There are three forms of such a sampling grip including the grip of the Schlumberger Comb Sorter, the semi-automatic hand-driven grip of the Almeter apparatus, and the new automatic motor-driven grip of the Almeter.

A letter to the editor is presented about the measurement of the mean diameter of a blend of wool fibers through using the mean diameter of each component of the blend.

The article presents a letter to the editor concerning the variability of yield and fineness in length samples taken from bales of greasy wool.

A study is reported of the variability of yield and fineness measurements between core samples within 'unclassed' lots of Australian greasy wool. The lots taken as 'unclassed' are some consigned from the farm for bulk-classing. The variability is compared with that found in previous studies, for auction lots that had been classed. The results are discussed from the point of view of obtaining an adequate sample from lots of unclassed wool, and a comment is made on the effectiveness of wool-classing as it appears from the comparison. [ABSTRACT FROM AUTHOR]

The compressional behaviour of wool fibres at pressures ranging from medium to high is reported, and the effects on this behaviour of various fibre characteristics are determined experimentally. It is shown that the behaviour of a mass of wool fibres in compression can be adequately described by an equation of the form: d = aPb, where d is the density of the fibrous mass, P is the pressure, and a and b depend on such fibre parameters as yield, fineness, and crimp. A highly significant negative correlation is shown to exist between the percentage yield of greasy wools and the density of the fibrous mass at unit pressure, the relation being independent of fibre fineness. For scoured wools, there is a highly significant positive correlation between the mean fibre diameter and the density of the compressed mass. Although crimp and fineness are known to be positively correlated, it seems that each has a separate effect on the compressibility of scoured wool. For a limited range of man-made fibres, the compressional behaviour is similar to that of wool. [ABSTRACT FROM AUTHOR]

An account is given of an investigation in which air-flow measurements of fineness were made on individual core samples drawn from lots of scoured wool. From analyses of variance, estimates were made of between-bales, between-ends, and between-cores components of variance. These estimates suggest that the sampling precision (95 % confidence level) for lots of ten bales or more should be, at the worst, ±0-2 µm and may be better than ±0-1 µm for a sample consisting of two cores from each bale. An example is given in which the variability of fineness within a lot of greasy wool is compared with the variability within the same lot after it had been scoured and rebaled. [ABSTRACT FROM AUTHOR]

Studies of sampling variability relating to the measurement of yield and fineness of greasy wool have been published previously for auction lots of Australian wool in spinners-wool categories. This paper describes similar studies for auction lots of carding and inferior topmaking wools. As expected, the between-bales and within-bales variability proved higher for these wools than for the spinners wools. Nevertheless, present sampling practices are expected to give acceptable precision. [ABSTRACT FROM AUTHOR]

A survey is presented of measurements of the variability of yield, vegetable-matter content, and fineness between core samples within growers' or auction lots representing a variety of types of wool from the Australian clip. The pattern can be represented, in part, by a linear relationship between the within-bale standard deviation of a particular characteristic and the mean value of that characteristic for the lot. The data presented do not suggest that a change from the present sampling schedule is necessary. [ABSTRACT FROM AUTHOR]

A comparison is reported of fineness results obtained for 27 lots of scoured wool by the projection-microscope and air-flow methods. The sampling of the scoured wool was done by core-boring, and the cores were hand-carded before air-flow tests were made. The sub-samples for projection-microscope measurement were cut into snippets 1 mm long in order to obtain a length-biassed sample. The air-flow apparatus was calibrated with reference tops in five different forms. The results show that there exists a systematic difference between the air-flow and projection-microscope mean diameters of scoured wool when the air-flow instrument is calibrated with reference tops in the original state. A better agreement results by hand-carding the test samples of the reference tops, but the closest agreement is obtained by cutting, washing, and hand-carding these test samples so that their condition is similar to that of the core sample being tested. Provided that this kind of calibration were applied, the mean diameter of washed wool could be determined by air-flow testing of cored and hand-carded samples. [ABSTRACT FROM AUTHOR]

A satisfactory procedure has been found for determining with an air-flow meter the mean fineness of greasy wool sampled from bales by pressure-coring. A wool-model Shirley Analyser is used to remove dirt and vegetable matter from the washed wool cores. The Analyser also intimately mixes the wool fibres of a sample, which substantially improves the precision of the air-flow measurement. The effect of the Analyser on the measured value of fineness is investigated, and possible methods of calibration of the air-flow meter for use on wool cores are considered. A series of measurements on greasy-wool cores by both air-flow and projection-microscope methods is used as a basis for the suggested procedure. The precision of measurement is evaluated, and a particular calibration method is recommended. The mean fineness of a sample of greasy wool in core form can be found with a precision of ± 0 5 µm. [ABSTRACT FROM AUTHOR]

IWTO Core-test Regulations define the core sample that must be taken for yield measurement on a lot of greasy wool. On the basis of studies of fineness variability between and within bales, the expected sampling precision for mean fineness is calculated on the assumption that the same sample is used as a source of test specimens to be measured by a proposed modification of the air-flow-fineness method. Under present regulations, the expected precision is acceptable; it is emphasized, however, that, if core samples are to serve a dual purpose, variability of both yield and fineness must be considered in drawing up sampling schedules. [ABSTRACT FROM AUTHOR]

The article presents an examination of two auction lots of wool of AWB Type 432 and 433 for variability. The samples were hand-scoured, weighed, tested for fineness and for vegetable matter content. From the previous report, it was discussed that AWB Type 413 wool is of Super Style while AWB Types 432/3 are of Good Average Style. On an analysis of variance conducted, components of variance were taken for each lot and based on the results, it appears that the wool of AWB Type 432/3 is equivalent in variability of wool of AWB Type 413.