Webbing

1. A woven narrow fabric, the prime function of which is load bearing, generally with multiple plies.

Weed control matting

A fabric, laid directly on to the soil, which prevents weed growth t)y excluding sunlight. Slits in the fabric are used to allow seedlings or existing plants to grow. The fabric is sufficiently permeable to allow water to penetrate to the soil and to allow the soil to breathe, whilst Iii-niting evaporation of water from the soil.
note.. Some types also act as a mulch.

Weft hairline

An effect obtained by either colour and weave or printing, producing fine hair-like lines either lengthways (warp hairline) or widthways (weft hairline) in a fabric

Weft

1. Threads widthways in a fabric as woven.
note. Yarn intended for use as in 1.

Weft accumulator

A yarn accumulator used on shuttle-less weaving machines.

Weft bobbin

1. A support, slightly tapered, with or without a conical base, on which yam is spun or wound for use as weft.
2. The weft package wound on the support defined above.
3. A relatively long but narrow package of yam taken up on a cylindrical former during the draw-twisting of continuous filament yarns.

Weft carrier

A yarn carrier providing a supply of weft and driven positively through a shed.

Weft crackiness

A defect in woven fabrics in which fine weft way cracks or ribs (crackyweft) give the appearance of 'lines' distributed randomly across the whole part of the fabric width. They are usually associated with a slightly uneven pick spacing and are caused by varying friction between the warp and weft resulting in an uneven beat-up.

Weft detector

An electronic device for:
(i) monitoring the presence of weft during weaving, normally on nonshuttle weaving machines;
(ii) monitoring the time of arrival of the weft on relay air-jet weaving machines;
(iii) indicating that the weft on a pirn in a shuttle is becoming exhausted.
note: Mechanical devices which achieve the same objectives are weft forks and feeler motions.

Weft fork

A mechanical device for monitoring the presence of weft during weaving, normally on shuttle looms. (See also weft detector.)
note: If this device operates at one side of the warp, between the edge of the warp and the boxes, it is referred to as a 'side weft fork', but if it operates anywhere between the two edges of the warp, it is referred to as a 'centre weft fork'.

Weft Insertion

1. Any one of the various methods shuttle rapier water jet etc. for making a pick during weaving. 2. A marriage of warp knitting and weaving brought about by inserting a length of yarn across the width of the knitting elements and fastening the weft yarn between the needle loop and the underlap. (Also see METAP WEAVE-KNIT PROCESS.)

Weft insertion (warp knitting)

1. Descriptive of a machine in which weft threads are introduced between the back of the needles and the warp threads, across the complete width of the fabric.
2. Descriptive of a fabric that contains weft threads across the complete fabric width, each being positioned between the knitted loops and the underlaps of the fabric.

Weft knitting

A method of making a fabric by normal knitting means in which the loops made by each weft thread are formed substantially across the width of the fabric. It is characterized by the fact that each weft thread is fed more or less at right angles to the direction in which the fabric is produced.

Weft loop (defect)

A short length of weft yarn that is looped on the surface of the fabric or doubled back on itself in the fabric without snarling. The defect is associated with weft yarn that is not lively and may be caused by inadequate tension control in the shuttle, by shuttle bounce, by the reed being unsuitable for the fabric being woven, or by faulty setting of the weft fork etc. In the last case, it may be referred to as a 'centre loop' defect.

Weft rib

An effect produced by weaving two or more ends as one and by using a weft cover factor approximately twice the warp cover factor, so that the weft is made to bend round the warp, which remains substantially straight. This leads to the formation of rounded weft-faced cords running, down the fabric.