Transcriber's Note:

The cover image was created by the transcriber and is placed in the public domain.

PITMAN'S TEXTILE INDUSTRIES SERIES

Edited by Roberts Beaumont, M.Sc., M.I.Mech.E.

HOSIERY MANUFACTURE

HOSIERY
MANUFACTURE

BY

WILLIAM DAVIS M.A.

Principal of the Buceleuch Technical Institute, Hawick.

WITH 61 ILLUSTRATIONS

including many original photo-micrographs.

LONDON: SIR ISAAC PITMAN & SONS, LTD.

BATH, MELBOURNE and NEW YORK

Printed by Sir Isaac Pitman

& Sons, Ltd., London, Bath,

Melbourne and New York

PREFACE

This work is being issued at a period of unparalleled development in the industry of knitted fabrics, when our British manufacturers are straining every nerve towards attaining a dominating position in this vital branch of the production of textile goods. It is highly gratifying and full of promise to note the spirit of enterprise which animates our younger generation of manufacturers, and the keenness and alertness which permeate the industry at the present time. Increased concentration by our machine builders on the numerous mechanical improvements being brought out in rapid succession from time to time is certain to have a great influence on the further expansion of the industry, and has the effect of considerably extending the horizon to the maker of knitted goods. With so many new firms springing up in different parts of the country, there has arisen an increased demand for books dealing with the knitting industry, and this work is presented in the hope that it will do something towards satisfying this widespread desire. The study of looped fabric structure is wide in scope, and none the less difficult because, on a first view, it appears simple and elementary. The prospect of the maker of knitted goods of all kinds, is further enhanced by the enormous production possible on the present-day knitting machinery and on the fact that the garments are made ready-to-wear. In this work an effort is made to outline the principles underlying the technology of the industry, and endeavours have been made to clarify certain problems of fabric structure which require still greater attention from the students of technology before they can be regarded as solved. Emphasis has also been laid on the fundamentals of the knitting process as performed on various mechanisms, for, if these basic principles are clearly comprehended, the foundation is securely laid for a further grasp of the industry and its technology.

Special attention is given to the structure and properties of knitting yarns, for in this texture it can be said with truth that the yarn is the fabric, seeing that the bulk of the productions are made from the single thread looped upon itself. Several problems relating to the weight of knitted fabric and similar questions are fully demonstrated, and the formulae explained from fundamental principles. A contribution is also made to the difficult subject of the setting of looped textures, generally so imperfectly understood in its theoretical significance.

That this volume may contribute towards a fuller knowledge of the technology of the knitting industry is the earnest wish of the Author,

WILLIAM DAVIS.

Technical Institute,

Hawick, 1920.

CONTENTS

ILLUSTRATIONS

HOSIERY MANUFACTURE

CHAPTER I
Development of the Knitted Fabric

There has been in recent years an extraordinary development in the scope and application of the knitted fabric which may be traced to a variety of causes. The chief explanation of this growth is to be found in the structure of the knitted fabric itself, the qualities of which have made it pre-eminently suitable for special departments of textiles. In its most elementary form the knitted texture is composed of a series of loops hung in rows one upon the other and constructed from the curvings of a single thread which runs continuously through the fabric. One set of loops is formed on the preceding row and any particular stitch is dependent for its support on neighbouring stitches above, below, and on either side of it; if the thread becomes severed at any point the loops lose contact all round and a considerable opening is incurred. This is its chief defect, but also its outstanding advantage as a texture; it is a defect to have the structure destroyed with the severance of the single ground thread, but it is the mutual interdependence of loops which accounts for its valuable stretch and elasticity. By virtue of this elasticity it becomes eminently suitable for articles of underclothing which have to be worn in close proximity to the cuticle; the fabric is enabled to yield to the slightest movement of any part and thus prevents the wearer becoming uncomfortably conscious of the garment. An inherent yielding quality of the loops causes the article to stretch and adapt itself to minor irregularities of size and shape; if a garment is not exactly to dimensions, it contracts to a smaller or expands to a larger form. This property of stretch must not be unduly taken advantage of to cover up indifferent systems of manufacturing, but within certain limits the property is of great value for certain discrepancies. The knitted fabric is essentially a weft fabric, the thread being inserted crosswise into the texture after the manner of filling so that the entire structure presents a horizontal appearance which is most evident with ground-coloured stripes when the different colours show themselves crosswise. This proves a serious limitation to the scope of the plain knitted texture, for the clothing trades have small use for horizontal effects as compared with vertical coloured stripes. The knitted structure is quite different in property to woven cloth where one has two series of separate threads, one being termed the warp and running longitudinally in the fabric, whilst the other series is named the weft and is intersected with the warp in the process of weaving. The warp threads are pre-arranged to the correct length and in order of pattern on the warp beam whilst the threads of weft are inserted consecutively during the operation of weaving in the loom. This mode of intersecting separate series of yarns at right angles to each other causes the threads to exert a much firmer grip on each other and the resulting fabric is remarkable for its strength and rigidity. It is firm and durable in structure, and possessing comparatively little stretch, it does not yield to the ordinary strains to which it is subjected. It is pre-eminently the fabric to be used for garments of outer wear which have to stand the rough service of every-day life, where a combination of friction, bending and abrasion subject the fabric to a severe test of endurance. In the case of a knitted texture there is a right and a wrong side, or face and back, the face comprising the straight portions of the loops whilst on the back the curved loop portions predominate. Fig. 1 gives a view of a plain knitted fabric showing the right side or the face of the texture where the loops may be distinguished by a characteristic V-shape, these Vs fitting into each other in a vertical direction. This side of the fabric is always worn outermost, as it presents the most even surface whilst it is also the most perfect as all imperfections such as knots, etc., are drawn on to the back of the cloth. Fig. 2 shows the same fabric on the wrong side where it will be noted that the chief feature is a series of interlocking semi-circles which have a distinctly crosswise determination given to them. The appearance on the back is decidedly raw and uninteresting, the straightened V-shaped portions of the loops presenting a much more attractive aspect. On the other hand, most rotary frames work their fabrics with the back in full view of the worker, and in case of analysis it is the wrong side of the fabric which will yield the most definite results to the analyst, for by examination of the curved loops one can discern more easily the character of the pattern and the nature of the ornamentation.

Figs. l and 2

Peculiarities of Knitted Structure.—An examination of the photo-micrograph of the plain knitted fabric (back view) shown in Fig. 3 will demonstrate that the loops are intimately dependent on each other and that the slightest dislocation at any part will at once affect the adjacent area. The knitted fabric is extremely difficult to make absolutely perfect, because each stitch is worked on its own needle distinct from its neighbour, and the slightest irregularity of yarn delivery affects the whole stitch area concerned. If a loop is drawn tighter than the normal at any point, then it is curtailed in size and the adjacent loops have to enlarge themselves to fill out the allotted space. In the woven fabric a missing thread usually influences that portion of the fabric only, but if the main thread of a knitted structure be broken, the entire cloth may be disintegrated with the slightest pull. The interspaces between the loops shown in Fig. 3 are intimately connected with the elastic property, because if the spaces are closed up by tight knitting, the elasticity is considerably reduced, if, on the other hand, the spaces are too large, the fabric loses its equilibrium and a slight pull will cause it to lose its form. An exception to this may be found in the light-weight fabrics so much in demand in recent seasons for wearing in an intermediate position in winter whilst in summer they are worn outermost for lightness. These are purposely knitted flimsy in texture so as to economize material and for summer they are quite elegant and serviceable when manufactured in attractive colourings. For winter use they are possessed of a heat-retaining property which would not be expected from their bulk, but to attain the best results they must be worn under a fabric of stronger and more durable construction. The theory of these surprising results is that free interspaces act as so many air chambers which contribute to non-conductivity of heat by the garment. Face veils are usually very flimsy structures, but on account of the "still layer" of air retained in the vicinity of the face the heat is effectively retained just as if a fabric of much heavier construction were employed.

Fig. 3

This property should be fully investigated in a scientific manner in the light of increased cost of raw materials which has now become vital to the manufacturer and his public. In many circles weight of cloth is synonymous with warmth, but experience has shown that this is not the case and that the warmest garments are not always the heaviest. The latest converts to the light-weight article are the clothing departments of the services where, as a result of war experience they have altered many specifications to include fabrics much lighter in weight; formerly no gauge or sett could be too coarse and thick for their requirements, but now the products of all gauges in the equipment of the hosiery manufacturer are utilized. Now the matter is being brought more fully to the notice of the manufacturer on account of the great rise in the price of raw materials when it is essential to extract the utmost farthing of utility from every ounce of material. If we can more fully requisition the services of the "still layer of air" in this regard it will prove an inexpensive medium of clothing.

Knitting Trade Definition.—The meaning of the term hosiery has undergone a great expansion during the past decade and its present meaning is an eloquent testimony to the enormous growth which the trade has recently experienced. Originally the term had reference chiefly to articles of footwear, it was in this regard that the utility of the knitted stitch was first recognized. The feet form a delicately susceptible part of our anatomy and require special care in fabric selection. In walking the muscles and tendons of the foot are in constant action and it is of vital importance to the comfort of the individual that the footwear should be worked in the most suitable fabric. To have footwear in the woven texture is unthinkable if from no other reason than the seams which would be necessary, and to have one of these located at the heel or along the sole of the foot would render the wearer unable to walk in a very short period. There is further the matter of perspiration which occurs so profusely at the pedal extremities, and the knitted texture above all others is adapted to that intimate sort of interaction between skin and fabric which is required for the absorption of perspiration. It laps it up and gives it back again gradually in the form of vapour. In a fabric of less absorbent qualities the article would soon fill with moisture and giving rise to wetness cause considerable discomfort to the wearer. The term hosiery has greatly outgrown its original significance as applied to footwear only and now embraces underwear, articles used for intermediate garments and an increasing range of garments suited for outer wear. There are now very few departments of clothing into which the knitted texture has not penetrated. For outer garments it is not always advisable to employ the knitted texture in its entirety because it obviously does not possess all the properties needed, but great progress has been made in the direction of giving greater stability by a judicious use of the more rigid woven texture at given points. For example, in the knitted vest trade the garment edges are often bound with tapes of woven stuff, whilst the linings are invariably made from these materials. Incidentally the colour of these reinforcing materials is so chosen as to harmonize with the ground so that the whole garment is enhanced in general appearance. Similarly it is found that the plain knitted loop is neither heavy nor close enough to give adequate comfort for an outer garment, which deficiency has been attended to by the hosiery machine builders who have made such improvements on the machines as will enable much more yarn to be inserted in a given space. This increases the sett of the loops and the weight and rigidity of texture, so that fabrics may now be obtained which are almost equal to the woven fabric in resistant properties. Such modifications of fabric structure usually result in a pattern with a prevailing one-sided effect, the wrong side being deficient in appearance and style. The ordinary plain knitted stitch per se has little scope for ornamentation unless special machines are employed and where embellishment is required on a plain garment it often takes the form of added pieces of crochet.

Figs. 4, 5, 6 and 7

Crochet Work.—This is particularly useful in the trade for children's garments where many factories employ crochet workers who ornament the edges by crochet patterns worked in the same yarn. For the very tiny articles of this class it is often found uneconomical to employ machines, and in certain districts large numbers of such garments are produced by the hand crochet workers where the greatest freedom of loop selection is possible. The operation of hand crochet is illustrated in Figs. 6 and 7 where the hook is marked H; in Fig. 6 the hook with loop A upon it is about to grip a portion of the new yarn B, and in Fig. 7 this has been drawn through the old loop to add a new one to the chain. In this way one can have on a garment effects which could only be produced by changing to several types of machines, and when articles are small this changing is not economically sound. There are still a considerable number of these crochet workers in various parts of the United Kingdom notably in rural districts of Ireland and in various districts of Scotland and England. Many large firms have a number of such hands attached as an outside staff and they are useful for scrutinizing fashion publications and producing stitches with hand pins which may with good results be adapted to machine-made goods. They have subsidiary departments where customers are supplied with articles of distinctly novel character and for which they are prepared to pay enhanced prices. The freest of all mediums of ornamentation in this class is undoubtedly the crochet, and articles are often ornamented with distinctly elegant results by the use of the crochet hook. By this means yarn same as the ground is employed so as to render it homogeneous and elegance of pattern is due to the fact that the worker can select any point of the fabric for a new move of the pattern. We may have one style being worked at this point and an inch farther up a distinctly different pattern can be evolved. In many rural districts the workers have attained remarkable skill in pattern origination due to their life-long devotion to the handicraft; from the art view-point it is hoped that they will continue to secure such an outlet for their work as will reward their skill and devotion. It is admitted that such products may not hold their own in fierce competition of the open market, but "Man does not live by bread alone," and it is hoped that public taste for such artistic productions may be maintained and developed in contrast to the strictly utilitarian; the aesthetic sense is one which the British as a nation sadly lack.

CHAPTER II
Knitting and Weaving

Compared with the weaving branch of textiles the knitting industry has several outstanding advantages which are now being widely recognized. In weaving it is necessary to have a considerable amount of tackle and supplementary attachments if the fancy pattern trade is to be conducted. The knitted texture is essentially a one-sided composition, but when effects such as lace work, tuck stitches, or coloured styles are introduced these are notable on account of their effectiveness. For any of the machines used in the fancy departments of the knitting trade such as the Jacquard flat knitter, the lace or pearl machines, designs are in every case extremely effective, for minor alterations of the patterning devices produce a result which is at once distinctive and fancy elements show almost their full quota on the face. In the case of woven fabrics the loom and a complicated set of cards and shafts are needed to produce a figure of the most moderate dimensions. Colours in the ordinary twills only show about 50 per cent. of their effectiveness and the surface of the texture remains for the most part uniform. The producer of woven goods has an advantage in that he can make most forms of texture on one loom which he can alter in setting and tackle so as to give any degree of fineness or variety of design. The maker of knitted goods requires a series of entirely different machines in order to produce a full range of patterns and individual machines show but small variation in texture and weight. For any particular type of machine he requires to instal a series varying in the sett or gauge of the needles if a representative range of textures suitable for the changing seasons has to be devised. The average maker of knitted goods has to produce garments ready for the wearer, which renders his task more complicated, for he has to produce garments in full ranges of size and shape, thus combining the functions of fabric and garment producer. This has the advantage of enabling him to establish a more direct relationship with the wearer of his garments and most firms are adopting the policy of going direct to the retail, one which has had a most stimulating effect on the trade. This personal contact with the shopkeeper who places the goods in the hands of the wearer brings the manufacturer into close contact with the trend of public demand.

Hand Knitting.—The war period witnessed a remarkable revival of hand knitting which arose from a desire to send comforts to soldier relatives, and the enormous quantities of articles produced in this way greatly helped our men to withstand the rigorous conditions of active service in winter. The usual articles were scarves, gloves, knitted helmets, but, above all, thick warm socks. Knitting was performed on all occasions and it proved a great comfort to many who had relatives in dangerous situations. Knitting acts as a soothing tonic, and there is the added satisfaction of producing something of direct usefulness whilst the skilful hand knitter may impart touches of elegance and distinction not possible by machine. If hand knitting is to be skilfully performed it is necessary to give attention to the size of the knitting pins and that of the yarn in relation. The gauges of knitting pins or needles are recognized in this country by a series of numbers quoted by all instruction books dealing with the subject, Walker's bell-shaped knitting gauge being largely used by those who make hand knitting an occupation of leisure. This is cut bell-shaped in bright polished metal, the various numbers corresponding to the size of the openings in the gauge. The full range of gauges runs from 1 to 24 and the needles are named after these according as they fit the various apertures. The coarsest knitting-needle in general use is termed 1 and is of such a thickness that it will pass through the space marked 1; knitting-needle number 2 will exactly fit opening number 2 and so on till gauge 5 is reached. The apertures gradually decrease in size till the smallest recognized hand knitting-needle is termed 24 gauge. Thickness of needle must correspond to the size of yarn or, in other words, the yarn must suit the thickness of needle. It is the needle which determines the interspaces in the fabric, for a certain proportion must be allowed if the fabric is to possess the required elasticity and stretch. This property is essential to good wearing service, for if loops are stiff and stodgy in construction, due to over-tight knitting or meagre allowance of space, the fabric will not yield to the movements which occur in wear and will more rapidly give way under strain. The thicker the yarn the larger the space required and vice versâ, so that the needle determines the space which is to be allowed for any particular set of loops and should bear a definite relation to the thickness of yarn.

The Knitting Process.—The elementary operation of knitting by hand may be followed by referring to Figs. 4 and 5, which illustrate the stages and show the method in which the loops hang on the hand knitting pins. In this case flat work is being produced, the needle A being shown with the row of loops upon it whilst the needle B is being used to form a new row. The thread N is seen to continue from the loops already made and the pin B is being pushed through the end loop M so that it may catch a piece of the thread N and form a new loop similar to M. This is in the act of completion in Fig. 5 where a new piece of thread N has been drawn through and the old loop M is about to be discharged from needle A, this being replaced by a new loop N now hanging on needle B. This operation is continued stitch by stitch until all the loops spread on needle A are replaced by new loops transferred to needle B. When this is complete needle A is stripped of its stitches, and then is used to re-transfer the stitches from B back again to itself. By this operation it will be seen that the knitting operation as performed by hand on two pins is an alternate process; you transfer stitches from a needle working from right to left as in Fig. 4, and at the next course you work from left to right transferring the stitches back again. In this we do not obtain perfectly plain fabric but what is known as the garter pattern or one and one pearl-stitch. If it is desired to make plain work on two hand pins, the worker in turning the direction of knitting must push the needle into the old stitch in the reverse direction so as to effect a cast-off same as in the previous course. For the making of hose and half-hose on hand knitting-needles at least three pins are necessary to enable us to knit in circular form so as to produce the article to fit the foot. A more convenient method of knitting in a circle is to use four pins with the idle stitches evenly distributed over three of these pins and using the fourth to transfer in the manner already described. In this way each needle in turn is released and is used as the operating pin to form and transfer the loops in knitting. Even if the pins are correct in gauge in relation to the size of the yarn it is easy to make defective material or texture should the loops not be worked at a proper tension. Slack knitters and tight knitters are known according as they work with the thread slack or tight; in this it is well to strike the happy medium, too slack tension makes working to correct size very difficult, whilst too tight work reduces the speed of knitting and the wearing qualities of the article. Correct tension is generally in the region of that which gives reasonable freedom of motion to the knitter.

Branches of the Knitting Industry.—The Cut-up Trade.—The manufacturer of knitted goods has not only to produce the fabric but in most cases completes the garments ready for wear and has thus to act as manufacturer and tailor combined. By the cut-up trade is meant that branch where the garments are made by cutting the component pieces from a roll or web of cloth similar to the manner of a tailor of outer garments. This branch is usually associated with the cheaper grades of the knitted industry because the cutting can be done in standard sizes, many plies at one and the same time using automatic cutting devices such as the circular electric machine. Similarly the making-up and trimming of the garments is performed on the principle of mass production where output is based on a large number of articles being produced in exactly the same manner and to a standard type. In recent years the relative advantages of the cut method of manufacture as compared with other systems have undergone some modification. In the first place we have the waste which is a heavy item in the cut branch, for no matter how skilfully the pieces may be carved from the plies of fabric there is always a considerable number of waste pieces at corners, etc., which it is not possible to utilize. The problem of waste has become more serious since materials have risen so much in value and has tended to augment the price of such goods on the market. On the other hand, one of the great objections to the cut method of manufacture lies in the kind of seam or join used to piece the various sections together because owing to the frayed edges of severed loops, the seamer has to secure a hold several stitches from each edge and this gives rise to a bulky portion at the join which in underwear particularly proved a serious obstacle to comfort. The activities of machine makers have, however, in recent years been concentrated on devising methods of seaming which will minimize these deficiencies, and there are now several machines such as the flat-lock, which in place of taking the stitches so far from each edge introduce a number of threads to form a kind of bridge of texture of their own with the edge loops. This makes a secure join and at the same time gives a seam of little more than normal bulk.

The Full-Fashioned Trade.—As the term indicates, this section applies to articles made to the shape of the body these pieces being complete units with perfect selvedges which are afterwards united to form a garment where the edges are joined with comparatively little bulk of seam. The best examples of the full-fashioned trade are the garments produced on the Cotton's Patent Rotary frame which is built to work as many as twelve full width articles at the same time. This capacity of multi-production proves one of the strong points of the fashioned trade because the articles being worked identically effects a considerable reduction on the cost of making. Also the seam or join is made with selvedge loops which are perfect in formation so that the worker can use the end two loops as supports for the seaming thread which is of the same material as the garment and is thus inconspicuous and at the same time gives the correct elasticity. With the cut-up seam as at present practised clean-surfaced yarns have to be employed to the number of eight or more, and these are usually in white cotton which on a coloured garment at once proclaims its origin. In seaming fashioned goods each selvedge loop is joined to a corresponding stitch on the other side by the method termed "point-to-point" seaming, and under present conditions the slowness of this method and its greater cost has led many manufacturers of full-fashioned to reconsider seriously their position. The cup seamer can in many cases give a three-fold production and this is now being employed with success in such branches as the fashioned-hose trade. For high-class underwear, however, the point-to-point system still holds its own as being the best adapted for the work, and efforts are being made to have this type of machine accelerated to give increased production.

In the novelty trade such as that of knitted coats the articles are so varied in style and shape that they have to be fashioned singly on a hand machine, and it is being recognized that the full-fashioned system is too expensive if the firm is to do trade on a large scale. To increase production in such goods, therefore, the articles are often cut from knitted web separately to the style and shape desired and seamed on one or other of the mechanisms now being improved to give a suitable join for such goods. The distinct difference lies in the method of cutting which is individualistic so that full expression can be given to shape and modifications of fashion. To work the full-fashioned branch of the hosiery trade requires an enormous outlay for equipment, as these multi-garment machines run to a high figure and have to be installed in a series of gauges so as to present a sufficiently large assortment of textures to the market. For the cut-up trade, on the other hand, we can obtain a large quantity of fabric from a few circular frames; what remains is to cut the material to shape and trim and finish the garments.

The Seamless Branch.—This embraces another very important class of knitted fabrics which are produced for the most part without joins or seams and ready to fit the wearer. As most garments are circular in form this requires a plant of circular frames, or the flat knitter may be adapted for the making of circular fabric. The best example of this section is that of the hose and half-hose, or stockings and socks, which are required circular in form. Also large quantities of seamless gloves are placed on the market each season, these being worked with the fingers in the form of small circular bags to accommodate the fingers. Seamless fabric for hose and half-hose is of special value because any irregularities of texture instantly make themselves uncomfortably evident in footwear. The seamless hose trade is done on machines of small diameter with the needles arranged in circular form, and where suitable provision is made for the addition of pockets to accommodate the heel and toes. From machines of larger diameter are made garments such as nightdresses where the fabric is produced in the form of a large circular sack, a length of which is taken to form the body whilst similar circular pieces are produced on machines of smaller diameter for the sleeves. The practice of making garments of the sweater or "Jumper" class on circular frames is on the increase especially since machine types have been evolved which can make rib, plain, pearl and striped fabrics on one and the same machine with a suitable arrangement for narrowing. It stands to reason, however, that this method of making body garments does not allow of great accuracy of fit and that the greatest scope lies in garments which by their nature are of a loosely fitting description. At the same time the advent of the rib stitch in such machines enables the fabric to be given a latent amount of elasticity which can be utilized to fit the form of a slender person, whilst it can be stretched to accommodate an individual of more portly build.

CHAPTER III
Latch Needle Knitting

The latch needle is one of the indispensable instruments of the knitting industry, as was abundantly proved during the war period when shortage of needles threw large numbers of useful knitting machines into disuse, whilst inferior needles accounted for a great drop in efficiency. There is a great variety in form of the latch needle, but they are similar in essential features. A sketch of a normal type is given in Fig. 8 where the various parts are lettered thus: H = hook at the left extremity of the needle, L = latch, S = stem or shank of the needle, B = needle butt or heel, as it is often termed. The latch moves on a pivot from the dotted position when it shuts the hook to the normal position when the hook is open. The stem or shank varies in proportion of length according to the class of machine in which it is employed, whilst there is also a large diversity of forms of the needle heel or butt usually in the direction of strengthening by adding extra metal to withstand friction for large scale knitting.

Figs. 8, 9 and 10

Loop Formation with Latch Needles.—The matter of loop formation is of the greatest interest and importance in any study of knitting and is shown in detail by means of a series of sketches, 1 to 5 in Fig. 9, illustrating the operation at the various stages. This will be useful in studying any knitting frame, for an apparently complex piece of machinery may be quickly reduced to intelligible dimensions if the observer has a grasp of the process of loop formation. All machines using the latch needle, and they are many and varied, form their stitch on exactly the same principle, and when this is understood considerable progress has been made towards a thorough comprehension of the whole. Sections 1 to 5 of Fig. 9 represent the successive stages in stitch making, the needles being shown at the angle usually found in the flat knitting machine of the Lamb type. In Diagram 1 of the series the needle is shown in its normal non-operative position with the latch closed and the loop M inside it. In all knitting a division must be maintained between the old loop and the new yarn. In Diagram 2 the needle rises, and in so doing the old stitch M opens the latch L and passes on to the stem and the new yarn marked Y is in the act of being seized by the hook of the needle. In Diagram 3 the needle is noted to have sunk lower in position so that the old loop M closes the latch with the yarn Y inside, and the old loop covers the latch as shown. This stage is termed the "landing of the stitch" and in Diagram 4 the needle is noted to have dropped still farther, so that the old loop is pushed over the needle extremity and the new yarn drawn through the old loop M to form a complete stitch. Precautions have to be taken in the machine mechanism to have the old loop properly discharged over the needle end and the new yarn completely drawn through. When this is complete the needle again rises in its position as in Diagram 5, and in so doing the yarn inside the hook moves downwards and opens the latch preparatory to a new course of stitches.

Diagram 10 illustrates another important form of the latch needle known as the double-headed needle as it has a hook at each extremity. This instrument forms the basis of utility of a series of different machines such as the rib hose frame and the pearl knitter. In these cases the needle moves from one knitting stage into another discharging its loop from the upper or lower hook according to the pattern of the rib or pearl fabric.

The Flat Knitter.—One of the best known machines using the latch needle for its loop formation is the flat knitter which has an extensive use in the knitting industry. The scope of work produced on the flat knitter is truly wonderful and its great versatility of application accounts for its immense popularity. In addition to plain fabric it can make a large variety of fancy and reinforced stitches, which provide great extension to the textural scope of the knitted fabric, allowing it to be employed for a wider diversity of uses. Various colours can be introduced in stripe formation, and with attachments of Jacquard character or by the use of the double-headed needle the range of patterns is further diversified. In regard to making full-fashioned goods almost every form of garment can be made on it-pants, shirts, hose and half-hose, coats, vestings, caps and gloves, are only a few of the garments procurable. These can be fashioned by the worker to the required form and an interpretation can be given to symmetry and style of the human form. It has found an extensive application as a hand machine to the making of seamless gloves being used by the most progressive firms in the trade, and with the application of power it can be adapted with considerable success to the making of goods in the bulk. Hand machines are moderately priced so that to start a knitting factory with such a plant is not a really formidable proposition, quite a respectable equipment being procurable for a few hundred pounds; many a prosperous firm owes its initial successes to the adoption of the flat knitter and from this they have been able to launch larger schemes of development in the knitting business. With new starters in this trade to-day the flat knitting machine nearly always figures prominently when there is lack of capital, and on this basis quite a sound foundation may be laid.

A diagrammatic side view of the Lamb flat knitting machine is shown in Fig. 11 where the foundation of the machine consists of two needle beds or stages marked NB which are cut with tricks or grooves into which the needles are placed as shown, each side being a duplicate of the other. The needle is marked N and on it will be recognized such essentials as the latch L, the hook H, the butt or heel B working inside the cam-box CB. The thread T passes from its bobbin through the eye of the thread-carrier TC and the needle is pushed into its position in the cam-box by the spring marked S shown at the extremity of the needle beds. The fabric is marked F and is noted to pass down through the centre of the machine whilst at its extremity is attached a set of weights which act as a means of drawing the fabric from the needle ends as they are formed and if the needles are not being sufficiently well cleared the amount of weight is increased. The weights have to be raised from time to time to a higher position in contact with the fabric as it is being worked.

Figs. 11, 12, 13, 14, 15 and 16

Interior of Cam-box.—In this machine the principal functional part is the cam-box CB, and from this the knitting action is imparted to the needles. On this account a full view is given in Fig. 12 of the set of cams used in the knitting machine made by Messrs. W. and J. Foster of Preston. This set of cams is placed on each bed right and left and the constituent parts are indicated as follows. Parts A and B are termed the knitting cams, whilst the parts C, D and E combine to form what is known as the knock-up cam. The part E is a fixture, whilst the needle path is indicated curved, and through this the needle butts N are seen to be passing. From the previously-given description of the making of loops on the latch needle it should not be difficult to note that the cams working on the needle butts in the needle path combine to raise the needles to secure the yarn from the thread-carrier and, having received the yarn, the needles are pulled down again to complete the loop by drawing the new yarn through the old loop. The cams have a side-to-side motion and pass over the needle bed from right to left and again from left to right. In so doing they operate as follows: when the cam-box is passing from right to left the needle heels are made to ascend the left side of C and D and are drawn down again by the inside of cam B; when the action is reversed and the cam-box is drawn from left to right, the needle heels pass up the right side of cam D and are drawn down again by passing along the inside of cam A, this alternate action being repeated during the process of making plain work on the flat knitting machine.

The Rib Stitch.—One of the outstanding advantages of the flat knitter is the facility with which all kinds of rib stitches can be made, and this is due to the arrangement of the needle beds, where the needles of one side make their stitches in a direction contrary to those in the opposite side. In making rib work both sets of needles in back and front beds are in action at the same time; when the thread is supplied to the needles those on the back rise equally with those on the front and receive their share of yarn to form their own loops. Now it is clear that the knitting action on the right-hand needle is opposite in effect to that of a left-hand needle, this being expressed by the form of the knock-over of the stitch; the right-hand needles discharge their stitches to the left, whilst the left-hand needles discharge their stitches towards the right. It is this combination of stitches discharged in opposite directions which gives rise to the rib stitch which is such a valued adjunct to all forms of knitted texture. This difference in the direction of loop discharge causes one set of needles to form back-fabric stitches whilst the opposite needles knit right-side fabric stitches. The normal flat knitter has its two needle beds cut one-and-one, as shown in Fig. 13, each bed has accommodation for the same number of needles, these being set so as to pass up the centre between the opposite series. This is termed a one-and-one arrangement and the resulting fabric is known as the 1-and-1 rib stitch, one row of loops in a vertical direction appears as wrong-side fabric stitches, whilst the alternate rows work out as right-side fabric loops. This explains the great increase of elasticity found in rib texture as compared with plain because back-fabric stitches are always seeking the back. In their normal position they virtually pass to the back, only being visible on the face when stretch is applied in the width. The yarn in crossing from face to back and vice versâ undergoes a greatly increased amount of intersection which contracts the whole fabric in the width. This property is of the greatest practical value in garment manufacture, because the extremities are usually finished with a few inches of rib which enables the article to secure a firmer hold on the limb or part of the body and thus serves to keep it in position. The rib stitch is also an indispensable foundation of a number of textures which weigh much heavier than the plain, as it enables a greater weight of yarn to be inserted and the fabric is thereby increased greatly in bulk.

Tension and Weight.—The texture of a fabric on any given knitting machine can be varied according to a number of factors and of these quite an important one is the length of loop drawn by the needle. An examination of Fig. 11 will show that the needle beds on the flat knitting machine are stationary and that the needles during stitch formation draw the yarn over the top ends of the beds and obviously the length of the loop will depend on the distance which the needle is drawn below the edge of the needle bed, this distance being determined by the adjustment of the knitting cams A and B shown in Fig. 12.

Cam B is shown in a dotted position raised so as to draw a shorter loop and the length of the loop can be varied according to the height of either knitting cams A or B within certain limits. If the loop is drawn too long, that is, if the knitting cam is set too deep, the yarn may not stand the strain and breakage will result; on the other hand, if the loop is too short the fabric will appear stodgy in character.

Patterns Produced.—This type of knitting machine has an extensive range of patterns and textures which can be obtained and amongst the first variations possible are those which result from an alteration of the needle arrangement. The normal setting is to have one needle in the front stage for one in the back stage, and these being arranged alternately give the ordinary 1-and-1 rib stitch. This is shown in Fig. 13, where the upper row of small circles represents the needles in the back bed or stage whilst the lower row gives those in the front stage. The next, Fig. 14, shows the needles in exactly the same sett except that the needles have been arranged to give the 2-and-2 rib pattern, this being shown in diagrammatic enlargement in Fig. 16 at the side. The third sett of needles given in Fig. 15 represents the arrangement for a 3-and-1 rib pattern where every third needle only is allowed to remain in the front stage whilst the back stage retains its full complement. From these examples it will be clear that by altering needles in this way to any scheme a large variety of rib effects may be produced, nor need the arrangement be uniform throughout the width, for the borders may be in one pattern and the ground or interior in another. Novel effects in imitation of lace work may also be produced by leaving a needle out of one or other of the beds which makes an opening in the fabric which can be manipulated to give an effect of a lace-like character.

Figs. 17, 18, 19 and 20

Manipulation of Knitting Cams.—Figs. 17 to 20 have been prepared to illustrate the manner in which the cams are altered to give certain well-known stitches in the flat knitting machine, and the construction is the same as Diagram 12, with corresponding letters for the various parts. On the left of the plate are arranged the cams as in the front bed whilst the right-hand arrangement gives the set of the cams in the back. In Fig. 17 the two beds are shown arranged for plain rib work where both back and front needles are in action at the same time. Fig. 18 shows the cam setting in front and back beds for making the well-known half-cardigan or royal rib which has played such an important part as the stitch for cardigan jackets supplied to the troops during the war period. It will be seen that on the front bed cam A is raised into what is termed a tucking position, that is, the needles are pushed up by D to receive the thread but are not drawn down far enough to have their loops discharged over the needle ends. At the same time the cams in the back bed are set for plain work and the needles there knit as usual at every course. The real stitch, however, does not appear until the direction of knitting is reversed, because the needles on the front bed are again pushed up to receive a second thread and on this occasion are drawn down the full distance by B to knock off the stitches. This means that on the front bed stitches are formed in double threads after every two courses whilst the back discharges its loops at every course, which enables a much greater weight of yarn to be inserted into the texture, making it more rigid and stable. The cams in Fig. 19 are arranged in front and back beds to produce the polka or full cardigan stitch, where double courses are worked on both front and back. This may be clear if we consider the cam arrangements as illustrated moving first to the right when the stitches on the front bed are "tucked" whilst those on the back bed knit to the position of cam A. In reversing the knitting to proceed to left, two yarns are drawn through in the front needles whilst no discharge takes place on the back. In this way the knitting occurs on the cardigan rib plan on both front and back needle beds and the resulting fabric is much heavier in weight than half-cardigan and when taken from the machine shows a strong tendency to expand in width owing to the yarn seeking to take up a more expanded position. The full cardigan stitch tends to be loose in character, the weight of material is greatly increased over plain 1-and-1 rib, but there is a lack of structural firmness and cohesion. In Fig. 20 the part C of the cam comes into the picture as being necessary to give circular work on the flat knitting machine. This can be drawn up out of action in both front and back beds by a small finger lever, and an examination of this arrangement will show that in going to the right the needles of the front bed will knit as usual, but in reversing, as shown on the right of Fig. 20, the needles pass completely under part D owing to the absence of part C and knitting is not performed; the cam portion D is raised by a spring to allow the needles to pass over the dotted position. It will thus be seen that to make circular work we arrange the cams on the front bed so that they will knit in going to right but miss in going to left, whilst in the opposite bed the reverse holds good. Thus a course of loops is made on the front with the back not knitting, alternated by a course made on the back with the front not knitting. The fabric's being worked from one yarn causes the loops to be joined at the edges and so a continuous length of circular webbing is produced.

CHAPTER IV
Types of Knitting Yarns

The qualities necessary for knitted goods have already been outlined as applied to the fabric, but if ideal results are to be secured, the yarns require to possess certain specific features of their own, for the most efficient textures can only be got by combining the qualities of yarn and fabric. The range of yarns covers a wide variety of material and systems of manufacture and the type selected depends entirely on the use to which it has to be applied; price is its primary consideration, and whether required for outer, intermediate or under garments is also important. Speaking generally, the knitting yarn should be open in texture, full in handle, and the material should be soft and comfortable to the touch. Except for some classes of outer wear the thread should have a plentiful proportion of surface-projecting fibres which are of value in covering raw loop formation.

Woollen Spun Yarns.—Yarns spun in the woollen system are still used to a considerable extent in the knitting trade, such having large scope in the more moderate priced qualities. The yarn is produced by the ordinary methods of woollen yarn spinning, the wool being teased, scribbled, carded, condensed and spun into threads on the woollen mule. The combined effect of these operations is to give a yarn which has its constituent fibres crossing and re-crossing at every angle so as to give a melange of fibres, confused at first sight only because these are arranged in a yarn regular in diameter and compact in structure. Carding and spinning are done in the grease so that goods made from them require a more liberal scouring and fulling. The best known type in the coarse variety of woollen-spun yarns is, perhaps, the wheeling, which is illustrated by means of photo-micrograph, Fig. 21, and given in the form of two-ply, but large numbers are used in three or more ply for goods of the coarsest gauge. The name Wheeling is probably derived from the early days of hand spinning on the wheel when the wool grown on the farm was dealt with by the farmer's daughter by means of the distaff and spindle. In this type of yarn the wool fibres were spun as they hung on the distaff, and the chief care of the spinster was to draw them out so as to present as even a strand as possible to the torsion of the whorl. The single yarns were therefore rather irregular, but these deficiencies were to a large extent overcome subsequently by folding two or three plies according to the weight desired. In the days of hand spinning it was deemed most easy to specialize in one uniform thickness of ground thread and obtain the thicker counts by twisting these threads two or more ply. The wheeling yarns as made to-day partake very much of the same character; they are spun from the coarser grades of wool where long and short fibres are used promiscuously, all of which features may be noted by an examination of photo-micrograph 21 which gives the thread original magnified forty-fold. Fig. 22 gives a similar enlargement under the microscope of a yarn of the same class as used for utility wear at a moderate price, this yarn is three-fold and is spun on the woollen system with fibres showing in every variety of angle. The three-ply yarn shows very dense and gives a garment in a coarse gauge with considerable weight and of most serviceable character; it is found very adaptable for thick woollen socks for artisan wear.

Fig. 21

Fig. 22

Lamb's Wool Yarns.—The term lamb's wool as used in the knitting industry does not confine its connotation to the product of the lamb during its first six months of growth, although such yarns would naturally be included in the first scope of the term. Naturally the growth on the lamb during the first half-year is of the softest description and greatly esteemed for many classes of knitted goods where a kindly feel is of the utmost value. The term has to-day a much wider definition, and includes yarns spun from the shorter staples on the woollen system, so that such goods are well covered with surface material and further offer a good basis for brushing on the teasles or gig, thus increasing the softness considerably. Fig. 23 gives a photo-micrograph of one of the finer classes of lamb's wool yarns where the crossing and re-crossing amongst the constituent fibres is very well displayed along with the loose open form of the thread. The openness of texture proclaims this variety as being eminently suitable for the underwear branch of the business and these made into garments of moderate price give excellent service. In this sample the fibres are very regular in diameter, the thread is well constructed and will be sound in respect of absorbent quality.

Fig. 23

Shetland Yarns.—This is another example of a designation employed in the knitting trade which has wandered far from its original meaning. The name has primary reference to yarns and fabrics produced from the material taken from the Shetland breed of sheep which give wool of excellent soft handling properties. These wools occur in natural colours, brown, grey and black being found in addition to the predominating white. The fibre is soft, exceedingly agreeable to handle, and has been largely used for the industry from the pioneer days of the hand knitting. The word Shetland as now known in the trade has shown a distinct tendency to deteriorate in connotation and most generally means yarns of coarse character, carded and spun on the woollen system with a certain proportion of fibre of nondescript character mixed. These fibres are usually dark in colour and mixed along with the white wool give a tint known as "Natural"; the tints are most serviceable for utility undergarments in regular wear as they obscure soiling and allow of longer inter-laundry periods. Pure white articles are quickly soiled, the "Natural" garments can give a longer period of usefulness without sacrificing real cleanliness. In times of scarcity of material and in absence of laundry facilities, these natural coloured garments prove distinct aids to economy. Formerly the natural tint in a garment was at once a sign of inferiority and low grade, but now wools of expensive character are mixed with 5 to 10 per cent. of freshly-dyed fibre of pleasing effect to give better service. There has latterly been a tendency to increase the proportion of dark-coloured fibres and give a wider colour expression; in place of the ordinary brown, fawn and grey, other varieties bolder in aspect are utilized.

Fig. 24
2-PLY SHETLAND NATURAL YARN SHOWING DARK FIBRES INTERMIXED

Fingering Yarns.—The term fingering is widely known in the trade and is a clear reference to the era of hand spinning on the wheel when the fibres were drawn through the fingers preparatory to the addition of torsion, this "fingering" being a domestic attempt to establish a certain amount of parallelism amongst the fibres. Wools of longer staple were employed for these productions which may be regarded as the prototype of the modern worsted thread. The attempt to render the fibres parallel by hand cannot be completely successful, but the worker rejected the shorter material which was not incorporated in the thread, whilst the longer residual fibres were spun with rather more twist than was usual with pure woollen yarns. The fingering yarn as now known is spun from the better classes of medium-stapled wool and is usually found in three or four-ply for the better class woollen hose trade. It gives a good quality article which felts less than the woollen spun and has increased durable qualities, the three-ply giving a considerably augmented strength to the article. The principle of worsted spinning as practised in the Bradford district for weaving yarns is not suitable for the knitting industry. As a rule the twist is too hard, and even with slack twist the structure is scarcely suitable, not being open enough and having too little surface fibre. A fingering yarn largely used for the footwear trade is given in photo-micrograph at Fig. 25, where the thread is noted to be three-fold; the single strands show a firm twist, but at the same time there is visible a fair percentage of surface material which makes the yarn suitable for covering the interstices and contributing to fabric consistency. The qualities of this particular yarn have been tested by long experience in use and have proved ideal when the right kind of wool is used as foundation.

Fig. 25

Fig. 26

Worsted Underwear Yarns.—A view of a typical yarn as used for the light-weight underwear branch of the knitting business is given in Fig. 26, which represents a two-fold hosiery yarn used for light-weight shirts and pants, but more particularly for ladies' garments. Extreme fibre parallelism is the chief feature of this yarn structure, the fibres being meticulously pulled into line with each other by the teeth of the comber. The next points important to observe are the spaces shown between the individual fibres which ensure adequate ventilation and absorbency, along with the requisite elasticity. The twist in the single is very slight and the strength is obtained by folding the two single strands together. At the same time a sufficiency of surface material is present to insure correct cover for the loops so as to remove rawness of structure and impart a "skin" to the cloth.

The yarns illustrated in micro-photos 27 and 28 may be regarded as typical structures employed for the great bulk of the trade in underwear, these being samples of the widely-known dry-spun yarns on the French system. As compared with the method of producing worsted yarns in the weaving trade, this system of dry spinning is so called because no oil is added to the sliver in preparation; the system of combing adopted deals with shorter and less valuable wools and moderately priced yarns are feasible. Openness of character is best secured by imparting twist on the ordinary woollen mule, where the thread is torsioned intermittently in long lengths, during which operation a certain proportion of the fibres are thrown to the surface, as clearly shown in Fig. 27. The yarn is two-ply with a fair twist in the two-fold, whilst the singles have quite a small amount of torsion. The extraneous material prominent in this sample 27 is a valuable feature in the success of the yarn for the knitting trade. Fig. 28 gives a view of a thread of the same character but rendered denser in form on account of its three-fold character. This is an excellent sample of a yarn giving splendid service in wear and the production of which has caused a most flourishing spinning industry to be established in continental countries.

Fig. 27

Fig. 28

In this prosperity it is hoped the British spinner will participate more fully in the future, because it is a branch which lends itself to enormous production on a large scale, the usual way of doing the trade being for one mill to concentrate on few counts so as to have a minimum alteration in the setting of machinery. In addition the spinner requires to instal the right kind of combing plant which, it is satisfactory to learn, can be made very efficiently in this country; the British machine builder has risen to the occasion, and it is to be hoped that the spinner will follow quickly in his wake and prove equal to the enormous call for this class of yarn. These yarns are often referred to in the trade variously as botany yarns, or cashmere yarns, although the latter is in reality a misnomer, having original reference to the product of the Cashmere goat indigenous to the Himalaya Mountains in Northern India.

CHAPTER V
Counts of Yarn

Within recent years a great improvement has been effected in the matter of yarn numbering for the hosiery trade. Formerly a number of systems were in vogue which were distinctly local in their character and application, but these now tend to confine themselves to the standards common to other branches of textiles. Most yarns can be classed under the worsted, cotton or silk systems; woollen yarns spun on the Borders of Scotland are based on the Galashiels counts, whilst those from Yorkshire are counted on the skein system. Artificial silk yarns are numbered on the denier system which has come into greater prominence recently in connection with the growth of artificial silk goods on the market. The more irrational and arbitrary methods of numbering yarns are rapidly declining in use and the great majority of yarns now supplied are given in one or other of the systems named.

Worsted Yarns, including those coming under the term cashmere, botany and mohair are numbered on the worsted system which has its basis in the number of 560-yd. hanks which weigh 1 lb. of 16 oz.

Cotton Yarns, including those spun from a mixture of cotton and wool under the term merino, and spun silk are estimated on the number of 840-yd. hanks which weigh 1 lb. of 16 oz. There is a reservation in the case of two-fold silk yarns, the counts giving the exact number whether single, two-fold, or three-fold.

Woollen Yarns.—Alloa is an important centre of hosiery yarns spinning, and a system used in this locality is based on the equivalent of the number of 240-yd. hanks which weigh 1 lb.

Woollen yarns spun on the Scottish Borders are calculated on the Galashiels method which is equivalent to the number of 200-yd. hanks in 1 lb. The Yorkshire woollen skein system is based on the number of yards per oz. which, brought into line with others, gives a basis of the number of 256-yd. hanks which weigh 1 lb. Leicester lamb's wool system is equivalent to the number of hanks of 176 yd. each in 1 lb.

Silk Yarns.—In addition to the spun silk yarns mentioned as being counted on the basis of the cotton hank of 840 yd., what is known as the Organzine silk system is given by the number of yards per oz.

Tram silk is calculated on the weight in drams of 1,000 yd., and in the case of artificial silk yarns the counts are gauged by the weight in deniers of 520 yd. There are ^1,600⁄₃ or 533⅓ deniers in 1 oz.

Yarn Testing for Counts.—This subject has been taken up with greater interest by hosiery manufacturers, who are now installing suitable apparatus for conducting the important test as to whether a yarn is up to standard in regard to counts. Variation in the yarn size at once reflects itself in the weight per dozen garments, the usual trade basis, and with increased prices of yarns these tests are likely to become more prevalent in the future. Compared with the weaving trade the question of gauging the size of a yarn by the method of inspection and handling is by no means effective on account of the loose nature of many knitting yarns; in general they appear to have much less weight than their diameter would lead the observer to suppose. In weaving yarns the twist is much more decided in effect, but in hosiery materials accurate estimation can only be performed by making a calculation based on the weight of a given length of the sample. A number of simple devices are on the market whereby the counts of yarn can be accurately determined by weighing a given number of threads cut to a certain template according to the yarn system, and these instruments are being largely employed in cases where the overseer is too busy to give the matter personal attention. An intelligent yarn foreman, however, prefers the method of weighing off a given length of the thread and finding the counts by direct calculation or by the aid of an assimilating table. He can also devise short ways of making the calculation of counts adapted to the class of yarns being handled in greatest numbers, and these do not depend for their accuracy on any accidental mechanical factors.

Let it be supposed that the custom in a factory is to test a yarn by unravelling a length of 20 yd. and finding the weight of this in grains. In each calculation the proportion will be repeated of finding the number of yards in 1 lb. or 7,000 grains. Again, if the prevailing counts be worsted, then this will involve 560 in each calculation as in the following example.

Example 1.—On unreeling a yarn it is found that a length of 20 yd. weighs 10 grains, find the counts in worsted.

By proportion, if there are 20 yd. in 10 grains, the yards in 1 lb. or 7,000 grains will give the yards per lb. This obtained, we divide by 560 the length of the worsted hank to obtain the counts thus—

Example 2.—A worsted hosiery yarn is tested and 20 yd. are found to weigh 35 grains, find the counts.

If these two examples be observed it will be noted that for every calculation of this type such as a yarnman might be expected to make frequently, the common numbers are 20 × 7,000
560 = 250. These will occur in every calculation of this kind and this gives a short method of getting the result, for in place of using these three factors we take the resultant 250 as shown and divide the weight of grains into it.

Example 3.—Find the counts of a cashmere hosiery yarn, 20 yd. of which weigh 24 grains.

Following the method indicated we can obtain this result at once by dividing 250 by 24 = 10·4 counts cashmere.

The other counts met with frequently is the cotton or merino system where the hank number is 840 and the value in all such calculations is given by the numbers—

Example 4.—Find the counts of a merino yarn of which 20 yd. weigh 14 grains.

Taking the value ⁵⁰⁰⁄₃ divide it by 14, thus—

Similarly, if working with dram weights and a standard length of 20 yd. we should devise a value for the figures constantly recurring and this would greatly simplify the calculation of the counts.

Example 5.—Find the counts in Galashiels or Scotch woollen system of a yarn, 20 yd. of which weigh 2 drams.

The first step is to find the yards in 1 lb. = 16 × 16 = 256 drams, and then divide by the hank length of 200 yd.—

In all calculations of this character the numbers 20 × 256
200 will occur and these reduced give a value of 25·6 which is taken as the constant and for all similar calculations the weight in drams is simply divided into this value to obtain the result.

Example 6.—Find the counts in Scotch woollen of a yarn, 20 yd. of which weigh 1·25 grains.

Taking the value as 25·6, this is divided by 1·25 = 20·4 cut woollen.

Sufficient has been given to show that it is comparatively easy to calculate counts of yarns regularly coming into the yarn store where we have a few standard hank lengths to consider along with the values obtained for each type of calculation met with in practice. Tables in each can be constructed from which the counts of yarn may be seen at a glance, the only work being to find the weight of the test length.

Yarn Conversion.—When two or more yarn classes are used in the same garment it is necessary for purposes of calculation to translate the counts into one or other of the systems, the most common system for choice. Thus, in cotton and wool, or silk and wool twist yarns, it may be necessary to make a calculation for counts and this cannot be affected unless both yarns are in the same denomination. The rule is to multiply the given counts by its own hank length and divide by the hank length of the yarn required.

Example 7.—Change 2/40's merino counts into worsted and Yorkshire skeins. 2/40's merino = 20's single, and by the rule—

To convert into skeins counts the hank length is 256, and the formula is given by—

Example 8.—Change 24/24 Scotch woollen into Alloa and skein systems. 24/24 = 12 cut single.

Example 9.—Find the equivalent of 40/2 spun silk in worsted and skeins counts. In silk the number is always the exact counts whether it be folded two or more ply. Thus, we have it stated as—

Example 10.—Find the yards of yarn in 3 lb. of 2/48's worsted and ¼ oz. of 60/2 spun silk respectively.

In 2/48's worsted 24 × 560 = yards in 1 lb., ∴ 24 × 560 × 3 = 40,320 yd. in 3 lb. 60/2 spun silk = 60 × 840 = yards in 1 lb. or 16 oz., and to obtain the length in ¼ oz. divide by 4 × 16—

Weight of Knitted Fabrics.—These calculations lead to examples where the weight of knitted fabric has to be found. The ordinary plain knitted loop in which the bulk of textures is worked consists really of a weft structure, that is, the yarns run predominantly crosswise, and are intersected with the preceding loops in the manner already described. In determining the weight of a given length of plain knitted fabric we require various factors, these being taken as they are on the frame. It is essential in the first place to know the counts of yarn employed, and the number of courses inserted per inch into the fabric, and again it is essential to know the width at which the fabric is being worked on the machine. Finally, it is necessary to estimate what is known as the "take-up," for the yarn is pushed into curved formation which "takes up" yarn about twice the width of the fabric by the intersecting of the yarn over the needles and this has a very definite influence on the weight.

Example 11.—Find the weight of 10 yd. of knitted fabric made from 2/20's worsted yarn with 18 courses per inch at a width of 32 in. on the needles. The take-up is 2, that is, to form one course of loops, a length of yarn equal to twice the width is required.

If the question of take-up be ignored for the moment, let the yarns be inserted as weft threads crosswise in the fabric and we shall have in 1 in. of cloth 18 courses or threads each 32 in. wide. This gives 18 × 32
36 = yards of yarn in 1 in. of cloth or 18 × 32 × 36
36 yards of yarn in 1 yd. of cloth × 10 for 10 yd., but from the yarn counts we know that the size is such that 2/20's worsted = 10 × 60 = yards in 1 lb., so that dividing the latter by this number of yards will give the weight of the fabric in pounds, thus—

But this is the weight if the yarns are straight in the fabric, which they are not, for there is a take-up of 2, that is, the weight has to be doubled—

1·03 × 2 = 2·06 lb. weight.

From this concrete example may be derived a formula which can be applied to all cases where the sufficient particulars are given, and following the above example we obtain—

Example 12.—

In this statement let the courses per inch or the sett be represented by S, the width by w, and the weight by W, counts = C, basis = B, length = L, from which we obtain the following equation—

Example 13.—

or-

S × w × L × T = W × C × B.

From this it follows that given any six of the seven factors we may obtain the seventh by substitution of values. Some of these possibilities are of academic interest only and are seldom required in practice, but a few examples may be given of the use of this formula.

Example 14.—Find the weight of 200 yd. of knitted webbing worked from 2/40's cashmere yarn with 28 courses per inch to a width of 48 in. with a take-up of 1·75.

Substituting as in formula 12—

Example 15.—Calculate the weight of fleecy fabric worked one thread 2/30's worsted yarn on face with 12 skeins yarn on back; the worsted has a take-up of 1·75, whilst the back yarn take-up is 2. There are 24 courses per inch of each thread, the length is 150 yd. and the width equivalent to 60 in.

For this example it is most expeditious to work out each yarn separately according to formula 12. For the face yarn the items will be stated thus—

for the woollen—

These added give 45 + 140·6 = 185·6 for the total weight in pounds.

Example 16.—Find the weight of a fabric plated as follows—

1-40/2 spun silk with take-up of 1·75

1-2/32's merino with take-up of 2·25

Length 320 yd., 24 courses per inch, 60 in. wide.

For the silk the counts 40/2 are taken as 40's single—

For merino—

Example 17.—Find the merino counts of yarn to produce 72 yd. of fabric 56 in. wide, 18 courses per inch, 24 lb. of material with a take-up in knitting of 2½.

The formula for this type of calculation can be derived from that given for finding the weight, all items being the same except that the weight is substituted for the counts.

Following formula 12—

Example 18.—Calculate the yarn counts in the Alloa system for a fabric 180 yd. long with 14 courses per inch, 66 in. wide, the take-up is 2 and the weight 24 lb.

Example 19.—Estimate the skein counts for a fabric 200 yd. long, 80 lb. in weight, 60 in. wide, 12 courses per inch, with a take-up of 2·25.

Example 20.—Give the worsted counts to reduce the weight to 60 lb. for example 19.

Example 21.—Calculate the length of knitted fabric which can be secured from 30 lb. of 2/42's cashmere, 22 courses per inch, 63 in. wide, take-up 1½.

This is obtained from formula 13 and may be stated thus—

Example 22.—Find the length per 100 lb. obtained in 2/30's merino, take-up 1·75, 21 courses per inch, 64 in. wide.

Example 23.—Find the length of rib fabric with a take-up of 3 obtained from 100 lb. of 20/20 Scotch woollen counts, 15 courses per inch, 60 in. wide.

Example 24.—Find the width at which a fabric will require to be worked to use 80 lb. of 2/16's worsted counts, take-up 2½, length 240 yd., 18 courses per inch.

This formula is identical to that used to find the length, except that the length is substituted for the width—

Example 25.—Find the width for a cotton fabric weighing 40 lb., 120 yd., 2/32's counts, 21 courses per inch, take-up is 2½.

Example 26.—Find the courses per inch required for a fabric worked in 18 skeins, 60 in. wide, take-up 175, 120 yd., 50 lb. weight. This is obtained from the same formula as Examples 24 and 25 except that the width is substituted for courses per inch.

CHAPTER VI
Folded Yarns

An interesting series of calculations useful to the knitting industry can be built up in connection with the methods of finding the resultant single counts of two or more yarns folded together. The counts of twist yarns is in the first instance of special application to the spinner, but there are many circumstances in which they may be useful in the yarn store of a hosiery factory. When two yarns of the same counts are twisted, the resultant equivalent single counts is obtained by dividing by 2, but when the yarns vary in size the proceeding is rather different. A common fault is to add the two counts together and divide by 2, but this gives a result which is entirely wrong. For purposes of comparison it is useful to have the equivalent single counts when two or more yarns are folded together, but the special interest to this branch lies in using two single yarns to take the place of one, in cases where supplies of the first material have run short. It is then of practical importance to have the two substitute yarns chosen from those in stock so that they approach as nearly as possible the size of the original.

Example 27.—Find the counts of 60's and 40's folded together. This example can be used to build up the formula from first principles. Take for convenience 60 hanks of the highest counts and twist this with an equal length of 60 hanks of the second counts stated thus—

therefore, 60 divided by 2½ gives 24 hanks of folded yarn in 1 lb. which is the counts 24's.

To find out a shorter rule for estimating the counts of a two-fold thread, let the first counts be represented by A, and the second counts by B, and let R be the resultant counts of yarns A and B folded together. Following the concrete example 27, it may be stated generally thus—

Example 28.—

The resultant counts R is obtained thus—

but

and making the fraction proper we obtain the rule—

Stated in words the rule is "To find the resultant counts of two threads folded together, multiply the two counts together and divide by their sum."

It often happens that a counts of a given size is required from two single yarns as in the frequent case of yarns running down before the contract for goods has been delivered. In such instances the resultant counts required is known and given one of the constituent singles, the other can be obtained by the rule: "Multiply the two counts together and divide by the difference." This can be proved in a general way from the last-found formula—

Example 29.—

in this equation the following also holds good

Similarly, if A is the missing counts of the two-fold yarn, the rule for A can be proved thus—

Examples in folded yarns.

Example 30.—Find the counts of 64's, 48's and 32's yarns folded together, and also give average when they are used separately one thread of each size in a garment. From the formula proved in Example 28 we have the following, taking the highest counts as starting-point—

therefore—

In the hosiery trade such yarns are more often used separately than folded together, when the more useful problem is to find the average counts of the three threads which is obtained by multiplying this result by the number of threads in the set, in this case 3.

Average counts = 14¹⁰⁄₁₃ × 3 = 44⁴⁄₁₃ average.

Example 31.—Give the resultant equivalent single counts of a silk and wool yarn composed of one thread of 2/40's worsted folded with a thread of 60/2 spun silk, also give the weight of each material in 110 lb. of garments and state the price ratios of worsted and silk respectively, taking the silk at 12s. 6d. per lb. and the worsted at 5s.

For the counts calculations both yarns have to be expressed in the same denomination and let the worsted system be taken. Transferring 60/2 silk, the counts is 60's as it stands and the transfer is made thus—

To find the counts formula 28 can be used, that is, multiply the two counts together and divide by their sum—

To obtain the weight ratio the calculation had better be worked thus—

90 ÷ 5½ = 16⁴⁄₁₁ as before.

For the weight proportion the total is given as 110 lb., which has to be divided in the ratio of the weight column, that is, of a total of 5½ lb., 1 lb. is silk and the remainder worsted—

For the price let the weight column be again used—

35/- ÷ 5½ = ⁶⁄_4¼ per lb.

also ⁵⁄₁₄ of cost is due to silk and ⁹⁄₁₄ due to worsted.

It is quite evident that this method of procedure yields results of the utmost interest and value to the maker of knitted goods.

Example 32.—Find the counts of 48's cashmere folded with 30's merino. Answer in merino system.

Change 48's cashmere into merino—

Using the rule as in (28)—

Example 33.—Find the resultant counts of 2/32's cashmere or worsted folded with 21's skeins counts. State answer in skeins system.

Transfer worsted to skeins—

By one method the counts is given by—

In this connection it might be useful to have the weight proportion of each, also the average counts if the two threads are not folded but placed side by side. Let the price of the 2/32's be 7/6 per lb., and that of the 21's skeins, 3/-per lb., when the cost per lb. of the combination is obtained as follows—

For the counts ³⁵⁄_2⅔ = 13⅛ if folded, but if separate, number × 2 will give the average counts 13⅛ × 2 = 26¼ average counts.

The weight percentage of each constituent in the garment is stated thus—

For the average price 2⅔ lb. = 12/6 = 4/8¼ per lb.

Example 34.—Find in Scotch system the resultant and average counts of 36/36 Scotch with 2/40's cotton.

Bringing the cotton to Scotch counts—

by the rule—

This rule can be applied twice in succession to find the counts of a three-fold yarn.

Example 35.—Find the counts of 80's, 40's and 20's folded together and give the average counts if they are used separately in a garment, one thread of each.

Taking 80's and 40's the resultant counts of these two is secured by the usual method—

This is now folded with the remaining counts 20, in a similar operation—

This result can be verified by the original method—

80 ÷ 7 = 11³⁄₇ × 3 = 34²⁄₇ average.

Example 36.—Give all useful particulars for the following combination of yarns in a garment—

Bring the worsted to cotton counts and the three yarns will then be in a like denomination—

Arranging these for the resultant counts, price and weight relationships—

80 ÷ 13·3 = 6·1 counts if twisted, and × 3 = 18·3 counts average.

69/5 ÷ 13·3 = 5/2 per lb. folded.

By computation from the table of prices it is found that

21·4 % of cost is due to silk

45·1 % of cost is due to worsted

33·5 % of cost is due to cotton.

For the weight percentage the proportions are taken from the weight column—

The remaining figure 49·68 % cotton is obtained by subtraction.

Example 37.—Find the useful particulars for a plated fabric composed of 2/20's worsted @ 8/6 per lb., 10's cotton @ 4/- per lb. The cotton yarn appears on the back and has 50 per cent. more take-up than the face.

15 ÷ 3 = 5's counts.     18/9 ÷ 3 = 6/3 per lb.

From the column of weights it is seen that this is divided equally between the two yarns; although the cotton is finer in diameter, yet the weights are made equal by extra take-up in loop formation.

Example 38.—A garment order is being executed from 2/42's yarn which runs short, 2/60's is in sufficient stock, and it is required to find what counts used with this will give the same weight of garment on the frame. Applying the difference rule—

Example 39.—Given two counts 48's and 24's in stock, find the third yarn needed to twist with these to obtain a counts equivalent to 10's single. The first step is to fold the two yarns together by the addition rule—

Then by the difference rule—

Example 40.—40's and 30's worsted are yarns in stock, find a third thread to fold with these to make a three-fold counts = 10's.

Using the difference rule—

To provide proof use the ordinary method of folding—

40 ÷ 4 = 10's counts.

If the third thread were wanted in another quality such as cotton, the answer would be secured by transfer—