Cotton Weaving and Designing / 6th Edition

by John T. Taylor

FIG. 137.

The end is made to cross from one side to the other by means of a doup heald. These healds consist of an ordinary heald with an extra half, generally called a “loose half” or slip. The method of knitting the doup heald will be understood from [Fig. 136]. It is obvious that when the doup is lifted at A, the end contained in the doup will be lifted up on the right-hand side of the end E. In order to bring the same end up on the left-hand side of E, the ends are drawn through the healds, as shown at [Fig. 137]. There are two ordinary staves, and the ends are drawn through them as for plain cloth with two staves. Then the end which is drawn through the first stave is crossed under the end which is drawn through the second stave, and is then drawn through the doup in the manner shown at [Fig. 136]. When the doup is lifted it will lift the crossing end A up on the right-hand side of the standard end B; but in order to do this easily the end must be slackened. This is done by taking all the crossing ends A from the warp beam over a slackening rod or vibrator, R; the other ends of the warp B are taken over the back rest in the ordinary manner. The slackener is usually in the form of a lever, one end of which can be lifted by the dobby or whatever shedding motion is used, and when the dobby lifts one end of the lever the rod is moved downward, thus slackening the warp which is drawn over the rod. Whenever the doup is lifted the crossing warp must be slackened, or it would cause the standard end B to be lifted, as it is crossed under it. In this manner when the doup is lifted the doup end is brought up on the right of the end B. In order to bring the same end up on the left of B, it is necessary to lift the first stave and the loose half of the doup. The first stave naturally takes the end up on the left-hand side of B, but it is necessary to lift the loose half in order to let the end go up on that side. It is usual to show the doup by a double line in the draft, the front line always representing the loose half. The pegging plan or lifting plan for the healds is for leno fabrics not usually shown on point paper, although it may be, just as easily as any other way. The usual way is to rule horizontal lines representing the staves and perpendicular lines representing the picks, and to put a / on the shafts to be lifted for each pick. It is easy to do this by continuing the lines which represent the shaft in the draft, and to make the pegging plan on the same lines by the side of the draft, as in [Fig. 137]. The two perpendicular lines one and two represent the picks, and the marks on the first pick are on the loose half, the doup, and the slackener; therefore all these will have to be lifted. (It is usual to peg the dobby to lift the loose half along with the doup to take the strain off the healds.) On the second pick the marks are on the loose half and the first stave, therefore these must be lifted for the second pick.

With the same draft as in [Fig. 137], a considerable variety of patterns can be made of a style known as crossover lenos. This style consists in weaving a number of picks plain, and then making a cross with the end. At [Fig. 138] the design draft and pegging plan are given for a “five and one” crossover leno. From the design it will be seen that the doup is required to be lifted for the first pick, and the first stave and loose half for the second pick, the second stave for the third pick, and so on. This lifting is shown in the pegging plan at the right of the draft, where on the first pick marks are put on the doup and loose half the slackener, and on the second pick on the loose half and first stave, and so on. There are in this pattern six picks to the round. The appearance of the cloth will be a bar of five picks plain, and then a crank or open space, in the middle of which is a single pick; the crack is caused by the crossing of the ends.

FIG. 138.

In gauzes and fabrics of this description, a thin open fabric in which the ends will not fray or slide is the object. The nature of the weave enables a firmer fabric to be obtained with a smaller number of ends and picks per inch than in ordinary weaving where the threads are not crossed.

FIG. 139.

FIG. 140.