In the previous instalment, author Isshi suggested a method of investigating the winding of roving and studied presser pressure on a roving package as one of the factors in the winding of roving.(1) Until then, there had been hardly any published reports concerning experiments on the subject. We have carried out investigations of other factors with the results which are summed up as follows:
1) When the frictional resistance of a flyer to roving is large, the roving becomes coarse in the early stage of winding, but depending on the character of the winding mechanism, factors such as roving tension and roving weight of unit length tend to approach a constant value as layers of roving increase in number.
2) We have clarified the correlation among the spindle position, the number of false twists of a roving and the roving weight, and proved quantitatively the usefulness of “rotafil” as an aid to a flyer.
3) Fluctuations in roving weight in each layer in the early stage of winding (when layers are small in number) are presumably caused, in the main, by improper diameter of the package. These fluctuations become gradually small as layers increase in number, because the self-controlling mechanism of winding corrects the improper diameter. Fluctuations in roving weight in the closing stage (when layers are large in number) are presumably caused, in the main, by improper relative revolutions of the bobbin and the flyer.
4) With a small number of relative revolutions of the bobbin and the flyer, roving weight initially appears large but later becomes proper gradually, due to the self operating control of the winding mechanism.
5) The winding pressure of the presser on the package is presumably one of the most important factors which make high-speed winding possible.

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Tension remaining in a yarn after it is laid on a beam is not equal to the original winding tension. Accordingly, no constant winding tension produces a uniform residual tension on all levels. The present article analyzes the distribution of residual tension in a yarn laid on a beam.
The force which a beam receives through a yarn wound on it is occasionaly sufficiently strong to break down the beam or demolish yarn layers. This article analyzes the force on the beam and its flanges. it analyzes also the stress contained in a yarn and a beam under plain-strain condition, assuming a yarn to be a curvilinear, anisotropic, elastic body.

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Variations in stress in a yarn beam produced by the yarns wound on it were examined and recorded during winding. The yarns used were nylon filament and cotton yarn. The stress in the beam core in axial and circumferential directions was examined with wire strain-gauges attached inside the beam core.
Data on the following subjects have been obtained from experimental results, with the aid of the theoretical results described in Part 2: 1) Yarn pressure on the core and the flanges of the beam 2) The anisotropy of the yarn layer. 3) The general applicability of the theory given in Part 2.

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Electrical methods are considered the best for detection of a weft incompletely inserted on the selvage opposite the nozzle of a water jet loom. With this in mind, research has been made and a detector developed. The research included efforts to find out the conditions that a detecting part and a detecting circuit must satisfy and to obtain data on developing a serviceable detector.
Results: 1) The electric resistance of wet yarns is less than several hundred M Ω, except in some special yarns.
2) The electrical insulation of the detecting part (which holds the electric feeler fingers) has to be as high as possible. The pulse wave generated from the feeling fingers by water-jetting is partially similar to the pulse generated by the contact of a weft.
3) A detecting circuit consisting of a computor circuit works fairly well, with very few wrong actions.
4) In an actual running test, a few wrong-actions developed. This needs looking into. Mean while, the detector we have developed is serviceable.

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