1. Concept
The two layers of fabric exchange with each other to form the character of the design. It is on these points of interchange that the two cloths are bound together. See Fig. 7.16.

 The two layers of fabric exchange with each other can form different effects. See Fig. 7.17 effects :Ⅰ, Ⅱ, Ⅲ, Ⅳ.
Ⅰ: Solid dark color on the face; and light color on the back.
Ⅱ: Solid light color on the face; and dark color on the back.
Ⅲ:Mixed color on the face and back.
Ⅳ:Mixed color on the face and back.
Fig. 7.17

(1) Design the patterns
(2) Select the base weaves which simple weaves are preferable due to the low number of shafts required.
(3) Color arrangement: the ratios are usually 1:1,2:1,2:2.
(4) Determine the size of the pattern, the repeat must be times of the base repeat.
(5) Draw the weaves in each part of the pattern.

1) Design the patterns, see Fig (A)
2) Plain weaves are selected as the base weaves of both layers
3) Color arrangement: X: Y =1: 1.
4) Arabic digital 1,2,3 etc. indicate X color threads while Roman numbers indicate Y color threads. See Fig. (B)
Fig (A) face back

4) Determine the size of the pattern. (2 repeats for this example)
5) Draw the weaves in each parts of the pattern. See Fig.
(B):

In Fig. 7.19 :

Arabic 1,2,3,4……indicate light color.

Roman Ⅰ,Ⅱ,Ⅲ,Ⅳ……indicate dark color Fig. 7.19

In Fig. 7.19 :


Arabic 1,2,3,4……indicate light color.
Roman Ⅰ,Ⅱ,Ⅲ,Ⅳ……indicate dark color
 Based on the known information the effects are clear:
I ---Solid light color: single cloth
II ---Mixed color: Face: dark ends interlace with light picks
III--- Mixed color: Face: light ends interlace with dark picks
IV--- Solid dark color

I :Concept
II :The main points of designing a tubular fabric
Ⅲ : Example

 Tubular weave is a kind of double weave in which both selvedges are joined. See Fig. 7.20.
Fig.7.20 tubular cloth

 (1) Selection of base weaves.
 (2) Arrangement of face and back threads.
 (3) Calculation of the number of total ends.
 (4) Drawing the weave

 The face weave and back weave should be the same. And the structure should be simple. The following weaves can be used as the bases: plain weave, 2/2 weft ribs, twill, etc. The shift in weft direction should be constant; otherwise, the selvedges are not even.

 Arrangement in warp direction should be 1 : 1; and in weft direction must be 1 : 1, otherwise, the selvedges can not be joined together properly.

3) Calculation of the number of total ends:
 To achieve a perfect continuation of the weave from face to back, certain rules of calculating the number of total ends in fabric have to be observed.
 Here, this formula is recommended:
M ot
= R o

Z

S y
Where: M ot
—total number of ends
R o
— base weave repeat
Z— the number of base weave repeat
S y
— shift in weft direction
If the base weave is plain, the M ot should be odd.
If the first pick passing from left to right, S y
If the first pick passing right to left, S y is negative.
is positive.

The cross section of the tubular fabrics (show flash ) is helpful to draw the weave since from that we can get the back weave . See Fig. 7.21
Where: (A)—face weave
(B)—back weave
(C)—cross section of the tubular fabric
(D)—weaving plan
Fig. 7.21

 (1) Draft : It is better using straight or grouped draft. If grouped draft is used, face ends should be drawn in the front shafts.
 (2) Denting: To counteract the tendency of the weft to contract more at the selvedges than in the centre of the cloth, each of the first and last three dents in the reed should have approximately one third less threads than that are drawn into the other dents.

 (3) Cords: In order to achieve an even selvedge, the selvedge cords which are thick threads are used on purpose to prevent an increase of warp density near the selvedges.
The cords are lifted up in such a manner that they are not woven in the fabric. These cords will be removed when the fabric is taken out of the loom.
Usually the cords are drawn into the last shaft.

1: Construct a interchange double weave, face and back weave 1/1 plain, arrangement, 1B 1L the pattern as Fig1.
Fig. 1
2: Construct a tubular weave, the base weave is 2/2 weft rib, and draw the cross section