CHAPTER II. WINDING AND WARPING, WARP YARN, WINDING FROM COP,

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CHAPTER II. WINDING AND WARPING, WARP YARN, WINDING FROM COP, BOBBIN AND HANK, BEAMING, SECTIONAL WARPING, BALL WARPING.

A

As has been previously mentioned, the weft yarn, when it leaves the mule, is in the requisite form for use at the loom, whilst the twist or warp yarn passes through at least three processes to fit it for the operation of weaving. The object of these processes is to coat the yarn with a layer of the adhesive substance necessary to protect it from the chafing in the loom, and, secondly, to coil the threads of warp upon a flanged roller evenly, so that they will unwind at the loom in a level sheet the width of the beam, and containing the requisite number of ends to make a cloth of desired dimensions. Bearing this object in view, it is not difficult to understand the three processes—winding, warping, and sizing.

The Twist.

The warp yarn is generally received by the manufacturer from the spinners in skips of 200/250lb. weight, and in the form of a cop. This has a cylindrical formation coned at each end, the more pointed end from which the yarn is unwound being called the nose, the opposite end the cop bottom. The best Oldham spinners make the cop about 7-1/2 inches long and 1-3/8 inches in diameter.

In judging twist yarn preference is given to the most even thread, round and free from motes, soft places, and snarls. The latter are caused by slack ends at the mule, the torsion of the thread taking up the loose yarn in the form of a twisted loop. A similar effect called a snick is caused by loose ends and inferior traverses at the winding frame, but wherever caused, the fault is most annoying to the weaver, and deteriorative to the cloth if intended for printing, as the loops rise after the cloth has received the impression of the pattern, showing white specks of an objectionable character. The twist cop should be of full dimensions, firm and hard copped, free from loose ends, and having clear apertures at the bottom for the winder’s skewer. Any fault in these respects causes an increased percentage of waste—most objectionable to a manufacturer.

The selection of a yarn for profitable use depends upon the foregoing qualities, but care must be taken to select for heavy sizing an openly spun yarn; for lightly sized printing cloths a strong, well-twisted yarn; for sateens and velveteens a level one; and for other goods yarns suitable to them.

Winding from Cops.

The object of the machine shown on Fig. 7 is to wind the yarn from the cop to a bobbin of about 4-1/2 inches lift—that is, having a barrel 1-1/2 inches diameter, and a head or flange at each end with a space between of 4-1/2 inches.

The machine, Fig. 7, is duplex, having similar parts on each side of the frame; on each side will be observed two rows of spindles driven from a central tin drum by bands; five inches from the top of the spindle is fixed a braid bearing a flannel washer on which the bobbins rest, and are driven round by the friction; the cops are fixed in a spindle rail, the end from each passing round a knee board covered with flannel, thence through a brush which serves a secondary object of cleansing the thread from loose dirt, and tightening it so as to prevent snicks being formed. In front of this brush is fixed a guide plate, slitted to prevent the winder lifting the thread so as to pass lumps too large to go through the slits.

FIG. 7.—WINDING MACHINE. To face pp. 22 and 23.

The brush and guide plate form a traverse, moving in slides alternately up and down to fill the bobbin with yarn, which is drawn from the cop through these “cleaners” by the friction between the bobbin and the revolving spindle. To enable a greater length of yarn to be wound on the bobbin, it is made of a barrel shape—i.e., of greater diameter at the middle than at the ends. Although the first few layers appear parallel, a greater increase of diameter is noticed at the centre of the lift afterwards, simply caused by allowing a longer dwell of the traverse than at the ends of the bobbin.

FIG. 8.

Fig. 8 shows an ingenious arrangement for obtaining the reciprocating motion, and at the same time the varying speed. A mangle wheel A is driven by pinion B, alternately engaging with the inside and outside of mangle wheel, thus reversing its direction of motion. On mangle wheel shaft a spur wheel C of eccentric motion gears with a similar one D on a stud, driving by a pinion E the rack F connected with the traverse. When the traverse is halfway of the bobbin, the mangle wheel is set opposite to the pinion B; and the small side of the eccentric C driving the large side of D. It is quite plain, then, that by this setting of the eccentric wheels the traverse will be at its slower speed, while as the mangle wheel revolves the larger side of C will drive D, and thus drive the traverse quicker as it gets near to the flange of the bobbin, and consequently nearer to its reversal. An exactly similar movement is obtained in another make of winding frame by means of a heart cam actuating a treadle, to one end of which is attached the traverse chain. As the larger or smaller part of the heart actuates the treadle lever, it is driven more quickly, while its normal speed is attained when contact is equi-distant between the apices. It will be observed that when the bobbin attains a larger diameter, even if the speed remains the same, the yarn is wound on more quickly in consequence of the bobbin’s greater circumference, but the speed is also increased because of the additional friction generated by the increased weight. To obviate this uneven strain on the yarn, the back row of spindles is often made to revolve more slowly than the front one, and as the bobbin increases in size it is placed on the back row. Winding from either throstle or ring bobbins is performed on a similar machine, modification having to be made in the spindle rail only, so as to obtain a proper position for the bobbin to unwind itself, the yarn coming off the bobbin at right angles to it and causing it to revolve on the modified spindle. Occasionally, where a manufacturer possessing the cop winding frames uses ring bobbins, the yarn is unwound from them in the ordinary way over the nose of the bobbin, and a little additional drag is applied.

Winding is performed by women, who are remunerated at the rate of about 1/4d. per lb. for 32’s T, and proportionately more for higher counts. The most frequent fault in the shape of the bobbin is in its being soft near one of the flanges: often dirt gathering in the guides causes this, or the traverse is not set half-way of the bobbin when the mangle wheel crab is opposite to the pinion. Gigging is the name given to winding off any excessively large bottoms by means of a slowly revolving bobbin, forming part of the winding frame. The speed of the driving drum averages 160 revolutions per minute. The traverses should have all gatherings of fluff, motes, etc., brushed out twice a-day.

FIG. 9.—BEAMING FRAME. To face pp. 24 and 25.

Winding from the Hank.

Coloured yarn used for dhootie and other striped cloth is received by the manufacturer in the hank, in which form it is dyed. When winding it on the ordinary bobbin for warp, only slight modifications of the winding frame are required. A swift is substituted for the spindle rail, and used for holding the hanks while unwinding them, while the kneeboard and brushes are absent. If the coloured yarn be used for weft for heading purposes, a pirn is substituted for the bobbin.

Other systems of winding have been introduced with only partial success, the principal one being a modification of drum-winding: a tube on which the yarn is wound rests horizontally on a revolving drum, the thread traverses the width of the drum, and thus a bobbin is built up, having level edges sufficiently firm without any protecting flanges. The ordinary drum-winding is similar, excepting that a flanged bobbin is used.

Beam-warping.

Three methods of warping are in use, but far ahead of the others in production stands the beaming system. To enable a sufficient number of threads to be gathered in one sheet for sizing purposes, say 2000, it is necessary to wind them first on a warper’s beam. This is a round roller, of wood, five inches in diameter, having an iron flange 20 inches diameter, and also an iron pivot at each end. This will hold 500 ends, each 15,000 to 20,000 yards in length, so that for a cloth of 2000 ends four beams are required at the sizing machine.

The beam-warping machine is for the purpose of warping the yarn from these 500 bobbins to a beam.

The bobbins from the winding frame are placed in a creel, generally a [V] creel, and shaped in plan view as its name indicates, each arm of the [V] being a frame containing tiers of pegs to hold 250 bobbins, the apex being nearest to the frame. The yarn passes through a reed, under and over several horizontal rollers, emerging in front through a guide comb, and thence to the beam. The beam is driven by friction, resting on a large drum making about 50 revolutions per minute; therefore, whatever the size of the beam may be—i.e., whether full or empty—the yarn, being pulled at the front, is travelling at a constant speed.

To avoid sudden strains of yarn the creel does not rest on the floor, but is suspended from overhead beams by rods. The older makes of beaming frames have a bed creel. Only one vertical creel is used, the other half of the bobbins being fixed in a horizontal frame. The [V] creel is preferable.

The whole frame occupies a space of about 16 by 18 feet.

The guide comb is of interesting construction. It is capable of expansion or contraction. Each tooth of the comb projects from an iron box, and is kept in position by being passed through the coils of several spiral springs; by means of a screw and nut at each end these springs can be compressed, thus diminishing the distance between the comb-teeth equally at all parts of the comb. When the expanding combs are used, far leveller beams are made than are otherwise attainable.

In the event of a thread breaking, the warper must have some arrangement for running the yarn back, so as to find the broken end to piece it up. This is obtained by six falling rods placed above seven fixed ones. When the machine is running forward the sheet of yarn passes between the fixed and loose rods, the latter resting on a slide. When the machine is reversed, the slide receives a slight impulse, allowing one rod to drop, say 3-1/2 feet, the yarn being suspended at the top by the fixed rods; whilst this rod is dropping it pushes the slide still further, and another drops, and so on, until when the sixth rod has fallen, twelve times 3-1/2 feet equalling 42 feet of yarn are taken up. This is ample for piecing purposes; indeed, the woman in attendance seldom finds it necessary to go so far.

FIG. 10.
FIG. 11.
PLATE II. To face pp. 26 and 27.

Prevention, however, is better than cure, and several machines are on the market fitted with stop motions to arrest the action of the machine at the breakage of a single end, and reducing the number of falling rods to two. One favourite system is to have a small bent wire, not unlike a hairpin, but about 1-1/4 inch in length, suspended from each thread and held in position by slots across the frame. This system is shown in Plate II., Figs. 10 and 11. Immediately under these pins are two nip rollers M (Fig. 10), revolving in contact, one of them borne on a movable centre, and attached to an upright lever N. This is immediately above an upright slide I, the bottom of which is connected to one end of a lever centred on the drum shaft of the frame. At the other end of the lever is a foot board and also the connection of a long rod with heavy balance weight always tending to press the footboard up, and consequently the slide down.

The machine is driven by a single open strap on the pulley, which, however, does not actuate the machine until it is pressed against the friction plate.

To start the machine, the footboard is pressed down, the slide consequently lifted and held in position by a hook which catches on the framework. By an inclined collar J, on the centre of the lever H (Fig. 11), the friction pulley and plate are pressed into contact and the machine is in motion. When an end breaks, the hair-pin drops between the nip rollers, pressing the loose one away from the other, therefore by means of the upright lever already referred to knocking off the catch H (Fig. 10). As soon as this is done the slide drops, and with it the lever O. The inclined collar relieves the pressure on the friction plate and the machine stops. The attendant pieces the broken end which is thus brought under his or her notice.

Beam warping machines are of various sizes, the most common being for 504 bobbins, the width being 9/8ths, or 54 inches between the flanges of beam. Other widths, of course, are in use, from 44 to 108 inches.

The waste of yarn, in the preparatory processes, indeed in all departments of mill work, is extremely important, and should be kept at as low a percentage as possible. At the winding frame the total waste should be 1 to 1-1/4 per cent., varying with the count and quality of yarn, and the total waste of warp yarn throughout the mill should not exceed 1-1/2 per cent. at the most.

For the purpose of measuring the length of yarn on the beam, each warping frame is supplied with a roller half-a-yard in circumference, round which the yarn passes; on the end of this roller is a worm driving a worm wheel B, of 54 teeth; on the stud carrying B is a second worm C, driving a worm wheel of 132 teeth. The worm only takes one tooth at each revolution, therefore a complete revolution of the first worm wheel represents a length of 27 yards having passed the measuring roller; this is equal to one tooth only on the second wheel B; therefore, a complete revolution of the latter means 3564 yards—technically called a wrap—1/2 × (54 × 132)/(1 × 1) = 3564. If a warp contains 4 wraps and 7 teeth, it is 14,445 yards long - 4 × 3564 + (7 × 27). For other warping calculations see Chapter IX.

The faults in beams are principally, bad, or no piecings, soft places caused by fine threads, or ends unevenly distributed in the combs, or by crooked flanges.

Where dhooties and other striped cloths are made, the warper has to be provided with a sheet showing how the coloured yarn is “laid in” at the side. This will be described under the heading of Dhooties. Where possible, all the coloured yarn is placed on one beam of the set, leaving the other beams all “grey,” as the undyed yarn is termed.

In any case of warping two counts of yarn on one beam, whether coloured or grey, allowance must be made for the different diameters of the threads.

Sectional Warping.

PLATE III.—SECTIONAL WARPING FRAME. To face pp. 28 and 29.

Where a warp is composed of two or more different counts of yarn, or where a ball warp is required without having recourse to the old circular warping mill, it is usual to use a sectional warping frame—Plate III.

As its name indicates the beam is warped in several sections called “cheeses,” of the usual diameter, but only about five inches in width. Several of these sections are afterwards slid on a bar, compressed at the ends and treated in the usual way. If required to be made into a ball, the ends are gathered into a loose rope and coiled in a balling machine. This latter method is generally adopted in those spinning mills where the yarn is warped by the spinner and sold in the ball. The sectional mill is a diminutive beaming frame of 400 bobbins running at a high speed. The yarn is warped on a square block between two circular plates, and when doffed is flangeless, thus necessitating careful treatment.

There is an interesting piece of apparatus attached to these machines for making all the cheeses of a uniform diameter when a certain fixed length has been wound on, and the increase of diameter is regulated automatically by the increment of length. The advantage of this is obvious when using two counts, say 30’s and 40’s, the warp in each case being, say, 1200 yards long.

If the diameter of warp were not regulated in any way, and the same strain placed on the yarn, the 30’s warp would be of greater diameter than the 40’s, or if of the same diameter the 40’s would be softer.

To obviate this a standard cheese is made; and in making it, the attendant releases the setting lever, and allows the stud to move freely in the vertical slot. With it is also released the scale lever, and the other parts which control the presser. A required length of warp is wound on the section block, say the length of a cut, which is indicated by the measuring roller, and the movement thus made by the presser is shown by the movement of the stud in the vertical slot. The hand-wheel is then turned until the stud has returned to its former position opposite the recess in the back of the slot. The position of the nut is then noted on the front scale, and tightened up by the handle shown. The setting lever is now brought forward, and the stud resumes its normal position in the recess, and the setting operation completed. In order that each succeeding section may be the exact size and length of its predecessor, the only attention necessary by the warper is to see that the revolution indicator points to the same figures. Thus, when all are run off together, their sizes diminish at an equal rate.

This machine is taking the place of the warping mill in the cotton trade, especially for coloured work.

Ball Warping on the Warping Mill.

Before beam warping was invented, ball warping was the system commonly employed in the preparation of yarn for sizing. This is a somewhat clumsy method, and so far as the cotton trade is concerned has been superseded by a modern system, excepting in one or two cotton manufacturing districts situated on the borders of Lancashire and Yorkshire, and for certain classes of goods in Bolton. A brief reference to it will not be out of place then, although, probably, the subject may interest few readers rather than many. The warping mill consists of a creel for bobbins, and a large circular frame. These are of different sizes, a common circumference being about 18 yards. This framework, or reel, is about 10 feet high, and thus forms a somewhat extensive cylinder. About 500 bobbins (which are wound from the cop in the ordinary manner) are placed in the creel and the ends from each are gathered together midway between the reel and the creel, at what is termed the heck box. This slides vertically between two posts, and has for its object the correct guidance of the yarn to the reel and also the keeping of the lease. The latter term will be understood by all connected with weaving as being the separation of the threads alternately, an arrangement which is used to enable the position of the ends being easily found in succeeding processes. Supposing there are 504 ends in the creel, these would pass through the heck box, and forming a loose rope be attached to the top of the mill. This revolves, and as by suitable mechanism the heck descends, the warp is coiled round the cylinder spirally, making in all several hundred yards, say 350. When the bottom of the mill is reached the direction of revolution is reversed, and a second layer wound upon the first one, and a third layer on the second, thus a warp of (3 × 504) 1512 ends is made 350 yards in length. Of course, the dimensions of the warp may be varied either in length or number of ends. The warp is now unwound from the mill and coiled in the form of a large ball. In districts where ball-warping is still used, the manufacturer is not usually his own sizer, and the warp, therefore, is now removed to a sizer’s establishment, where, after being weighted to the required extent, it is coiled into ball form again and returned. In the few places where ball-warping is still used the warping mill just described has been superseded by the sectional warping frame, as the ends are kept straighter, and a greater length run through in the same time. The uneven lengths in the old ball-warping mill, caused by the outside layers being longer than the inner ones, are also obviated.

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