CONTINUOUS TWILL AND THE TYPES OF CONTINUOUS TWILL | ANGLE OF TWILL.

CONTINUOUS TWILLS:

Warp Faced Twills:

In these types of twills the warp thread floats over all the picks in a repeat except one pick. The minimum repeat size required is 3. Examples of warp faced twills are 2/1, 3/1, 4/1, 5/1 etc.

Some examples of warp faced twills are shown in Fig.

Fig. A, C and D show a right handed or Z twill and Fig. B shows a left handed or ‘S’ twill.

Weft Faced Twills:

Weft Faced Twill

These twills are the reverse of the previous ones. In these weaves the weft thread floats over the warp on all picks in a repeat except one. Examples of weft faced twills are 1/2, 1/3, 1/4, 1/5 etc. Some types of weft faced twills are shown in Fig. 

Fig. B, C and D show a right handed or ‘Z’ twill and Fig. A shows left handed or ‘S’ twill.

Balanced and Unbalanced Twills:

Balanced and unbalanced Twill

In these types of twills the warp and weft floats may be equal or unequal. In other words the twills may be of the reversible or irreversible types. Accordingly they may be known as balanced and unbalanced twills. Examples of balanced twills are 2/2, 3/3, 4/4, 5/5 etc. Examples of unbalanced twills are 2/3, 4/2, 5/3 etc. The 2/2 twill is popularly known as “Gaberdene” weave. Fig. 4.3 A and B show designs for balanced and unbalanced twills and C and D show the interlacement diagrams of a 4/1 twill and 1/4 twill (warp faced) (weft faced).

Warp and Weft Faced Twills:

Warp and Weft faced Twill

In these twills the warp and weft floats may be equal or unequal with either the warp floats

predominating the weft floats and vice versa. Some examples of these twills are shown in Fig. 4.4 A, B and C respectively.

THE ANGLE OF TWILL:

The angle of twill is the angle between the diagonal twill line and an imaginary horizontal line or axis parallel to the weft. This angle is dependent on the ratio between the ends/inch and picks/inch in the cloth. When the warp ends/inch is equal to the weft picks/inch, the twill angle will be 45°. When the warp ends/inch exceeds the weft picks/inch the twill angle will be an obtuse angle i.e., >45° (high angle or steep twill). When the weft picks/inch exceeds the warp ends/inch, the twill angle will be an acute angle i.e., <45° (low angle or flat twill).