FLAX CULTURE.

Temuka Leader, Issue 1304, 17 February 1885, Page 3

FLAX CULTURE.

(Continuedfrom our last.) The next operation the flax straw undergoes is “ breaking and bruising,” i.e., to bruise the stems and break up the woody part or boon, so as to loosen it from the fibre. The breaking is effected in several ways, principally by machines having fluted iron rollers. Many machines have been aonstructed in which the bottom fluted rollers drive the top fluted rollers by contact of the flutes. The consequence is that the fibre, together with the woody boon or shieve, is ground between the shoulders of the flutes, and thereby greatly deteriorated, and an excess of waste fibre or tow produced in the subsequent operation of scutching. As already mentioned the flutes of the second pair of rollers are finer than those of the first pair. This is a very essential feature in good breaking machines, because byprarying the pitch of the flutings it is clear that their crimping action breaks the flax straw in different places with each differently fluted pair of rollers. - , Breaking machines are sometimes constructed with one large fluted cylinder, and from three to six fluted rollers working in itthe breaking takes place between the cylinder and the rollers. The flutes are necessarily ail of the same pitch, consequently thefiax straw is alwaysbrokan or crimped in the same places, and the same work is thus done over and over again. The effect produced by one of these machines is therefore little more than one pair of fluted rollers produces. For this reason breaking machines with several pairs of rollers are preferable to •machines with one cylinder and several rollers all fluted alike, because in the former case variety in the flutes, and consequently greatly increased action on the straw is obtainable. • For large scutch mills very powerful forsaking machines are necessary, . The mechanical bruising or breaking of flax straw is also effected by - f percussion,” or the action of beaters falling on the straw as it passes underneath them, The machine which effects this has an endless apron,'on which the straw is placed. This apron carries it forward to a pair of feed rollers, the top one ot which is free to rise and fall, according to the thickness of the straw passing under it; pressure is applied to it by means of lever* and weights or springs, immedir ajflly on |eaying these fepd roller? the straw passes on tp a large slowly revoly : ipg roller, and is acted upon by a series of long wood beaters, the ends of whiph, -falling on the roller, bruise apd prush the Straw (Jaripg its passage oyer it. The beaters arp made of wood, as already stated, and are lifted by a shaft, to which are affixed cams or lifters. When this shaft'revolves, these cams come in contact with arms projecting from the beaters and lift them up ; as soon as the cams lose

their contact with the beater arms by revolving, the beaters drop down on flax straw passing over the roller. The machine may have from 10 to 20 beaters, and as the cams are fixed round the main shaft helically, it follows that the beaters tall on the straw and rise again one after the other in the ordei in which the cams are fixed to the mam shaft. This is done in order to prevent the great shock to the machine which would take place if all the beaters rose and fell together. This mode of preparing the straw for the subsequent operation of scutching is reported on very favorably. It has not, however, come into extensive use, on account of its novelty. The next process which the flax straw undergoes is Scutching—This process, when carried out mechanically, may be done by (a) scutching mills or (b) scutching machines. The former are arranged in berths or stocks, which may vary in number up to 50 in one mill. The scutching instruments are blades made of tough flexible wood partially sharpened. The construction of a scutch mill is as follows A horizontal wrought-iron shaft of a length sufficient for the number of berths required is fixed in bearings £ gainst a row of pillars, which may be of wood or iron, according to circumstences. In foreign countries wood pillars are preferable, because cheaper. On this shaft are fixed, at stated intervals (usually about 2ft. 9in), wheels, technically called “ wiper rings.” Each of these rings carries a number of wood blades, generally five. Parallel with the shaft, and at a little distance from it, is placed an iron partition, firmly bolted at the foot and stayed at the top by brackets from the beam which unites the row of pillars already mentioned.

The wiper rings and their scutching blades work in openings or projections in this partition. These projections are also of iron, and are covered by suitable iron casings. One side of each partition is plain, the other side has a wedge-shaped slot or opening in it ; the lower edge of this slot is horizontal, and slightly higher than the centre of the wiper shaft. The front covering or casing of-each projection extends only down to this slot, in order to allow of the admission of the flax straw. The wiper rings are fixed on the shaft at intervals of about 2 feet 9 inches. The iron projections are 9 inches wide ; thus each workman has s space (usually called a berth) of 2 feet to stand in between each projection. The object of the partition is to cause the woody boon, dust, tow, etc., to fall in the place prepared for it, on the same side of the partition as the main shaft ; the floor behind the partition is much lower than that of the rest of the room, so as to give plenty of room below the blades, and to facilitate the removal of the boon or shieve, the scutching tow, etc.

Scutch mills are very liable to take fire, therefore the partition and its projections are made by preference of iron, so as to minimise the danger of fire and to isolate it in case of an outbreak. It is also of great importance to the health of the workmen that, their side of the room should be as free as possible from dust, scutching dust being extremely pernicious to the lungs. After the straw is broken, it is well shaken by hand to free it as much as possible from the boon; it is then carried into the scutching room, and placed in suitable handfuls, technically called “streaks,’’ on the table. The workmen stand in a row between this table and the partition, one in each of the recesses or berths between the projections ; the table has its top hinged at various places, to allow the workmen to pass through. Each workman stands with his left hand against the partition, and has the wedge-shaped slot in front of him. He takes a handful or streak of the broken straw from the table, and inserts one end of it in the slot through the uncovered part of the projection, resting the middle of the streak on the bottom edge of the slot, and sliding it gradually forward, so as to bring it well under the action of the scutching blades, which strike it in the direction of its length. When the shove or woody boon has been beaten out of the flax, he withdraws it and inserts the other half, to be similarly treated by the scotching blades. He then passes the handful of flax thus roughly scutched to his neighbour, who (reals it in exactly the same manner and finishes the operation, The scutching blades in this second operation are set closer to the slot than in the first operation, and consequently the flax undergoes a more thorough scutching. It is customary in scutch mills for the workmen to work in pairs ; the one who performs the first operation is technically called a “ buffer/' and the other a “ finisher” or “cleaner,” The finished flair is Anally moved from, the table and carried away to the stores. The operation of scutching necessarily causes a waste of fibre, because, however much care is used, some of the fibre is broken by the action of the scutching blade, and also by adhesion to portions of the woody part of the straw. This waste is called “ tow,” in some countries “Codilla;” and although less valuable than the original fibre, it has considerable value, being used, according to its quiilitv, for spinning yarns, for twines, sackings, canvas, linen, and many similar purposes. The scutching tow drops to the ground behind the partitions, and contains a large quantity of boon, which must be separated from it. This is done in the first instance by rough shaking by hand ; as, however, it is impossible to get the boon out of the tow in this manner, it is afterwards passed through 9 “ shakerwillow.” This qiaphiqe fur : nished in the front with a door, which rises and falls by means of cords uqd weights,

The operation of widowing is as follows i—A suitable quantity of tow is thrown into the machine, which is then closed by raising the door. The revolving beaters, which carry coarse teeth at their extremities, cause the low to revolve in the machine and shake and willow it to such a degree that ths dpst, dirt, apd boon, or wpp.dy particles of the flax-stem, become detached from the tow. The lighter particles and dust are drawn away or exhsusted from interior by' means of a fan fixed at the'hapk of t|ip maphipe, and arp blown through pipi'pg tp a re : peiver fiptsid© the bqilding. The heavier partiples drop through the grids of the machine into a receptacle underneath, and are removed from time to time.

When the tow has remained sufficiently long in the machine . (a few minutes

usually suffice), the door is let down and assumes a horizontal position. By the action of the beaters the tow is then deposited on the door, whence it is removed in its cleaned condition by the attendant. In this machine almost all the boon is taken out of the tow, which is then packed in bales ready for sale. The quality of the tow depends on the quality of the flax and its treatment; some qualities of tow are so good that they fetch as high prices as some qualities of flax.

The great improvement that has taken place of late years in the construction of machines fsr preparing and spinning tow has caused it lo rise very much in value. The principal point in scutching is to make,as little tow as possible ; the next point is to send the tow into the market as clean and free from boon as possible ; so as to ensure a high price for it. The boon which drops from the straw during its passage through the breaking machine, and that produced by shaking it immediately afterwards, is taken out and burnt under the boiler as fuel; the boon resulting from the scutching is also removed and burnt under the boiler after the tow has been freed from it by the shake-willow already mentioned. This machine is best placed in a shed outside the main building, driving power being conveyed to it by means of a strap from a pulley on the main shaft. Experience proves that with a suitably constructed boiler and engine, the woody part of the flax straw or boon is quite sufficient to generate the steam required for driving all the machinery in a scutch mill. This is a very important feature in this branch of industry, as many people have been deterred from establishing scutch mills on account of the supposed expense of fuel; the boon or ligneous part of the straw resulting from the operation of breaking and scutching is amply sufficient, however, to preclude the necessity of any additional fuel. Scutch mills may also be driven by water power, or, in the case of small cultivators, by cattle gear. Machine scutching is effected by means of a revolving drum or cylinder, which is placed in a cast-iron frame, covered with sheet iron. Round the periphery of this drum, and parallel to its axis, are fixed tough, flexible wood blades, the leading edges of which are sharpened ; at the back of each blade is placed a row of semi-circular metal scrapers, resembling finger nails, and immediately behind them a projecting metal blade. In the front of the machine are two iron stocks or face, pivoted at their base, and adjustable by means of screws and lock nuts, so as to allow of the stocks being set nearer to or further from the revolving blades. To the inside of the stocks are curevd spring plates, also adjustable by screws and nuts; at each side of the machine there is an opening in the cast-iron frame to allow the flax straw to enter. The operation of scutching as follows : —The .workman takes a handful or streak of the broken straw, and, standing in front of one of the stocks, he inserts one end of the straw through the opening at the side and retains the other end in his hands, resting it on the top of the stock. The revolving blades immediately begin to strike it in the direction of its length ; the metal scrapers already mentioned serve to bring new fibres under the action of the blades. These scrapers imitate the action of the workmen, who when scutching by hand run their fingers from time to time through the fibres in process of being scutched, in order to increase the scutching effect by exposing different portions to the action of the blade. Meantime, the workman gradually slides the straw towards the centre of the machine, and withdraws it through the space between the two stocks, Ha then inserts the other (unscutched) end of the straw at the side opening as before described. Having thus rough-scutched the handful or streak, he hands it to his neighbor, who treats it in exactly the same manner ; as, however, his stock is set nearer to the revolving blades, their action is more searching, and thus the flax is finished, It will be seen that each machine is attended by iwo workmen—a “buffer” and a “ finisher.”

These machines are usually placed in a row side by side, each machine being independent of the others. Instead of the wiper shaft, as shown in the preceding plan of scutch works, the shaft in the breaker room is prolonged the whole length of the building, and carried by brackets in the wall, On this shaft are placed the pulleys which drive the scutching machines.

At the back of the machines is, placed a flue connected with each machine, and with a fan or blower, which draws off the dust, straw, or woody boon, tow, etc., from the machines, and delivers them outside the building, to be treated as already described j the tow being saved, and the boon used as fuel.

In this manner the scutching room in kept free from dust and dirt. The broken straw is carried to the table, and the scutched flax removed through the door as already described, (To he Continued.)