Transcript Document

7.3 Interchanging double cloth
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.
Various effects

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
2. The steps of development
of interchanging double cloth
(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.
Example 1 :
Construct an interchange double cloth
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):
Example 2:
Indicate the effects of the each part
In Fig. 7.19 :
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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
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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
7.4 Tubular cloths
I :Concept
II :The main points of designing a tubular fabric
Ⅲ : Example
I Concept:

Tubular weave is a kind of double weave in which both selvedges
are joined. See Fig. 7.20.
Fig.7.20 tubular cloth
II The main points of
designing a tubular fabric:
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(1) Selection of base weaves.
(2) Arrangement of face and back threads.
(3) Calculation of the number of total ends.
(4) Drawing the weave
1) Selection of base weaves:

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.
2) Arrangement of face and back threads:

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:
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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:
Mot = R o  Z  S y
Where: Mot—total number of ends
Ro— base weave repeat
Z— the number of base weave repeat
Sy— shift in weft direction
If the base weave is plain, the Mot should be odd.
If the first pick passing from left to right, Sy is negative.
If the first pick passing right to left, Sy is positive.
4) Drawing the weave:
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
Pay attention for weaving plan:
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(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.
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(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.
Home works:
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