SYMBOLIC REPRESENTATION OF PEG-PLAN

The next step in describing the fabric design is to specify which harnesses will be lifted and which harnesses will be lowered during each pick in the unit cell of the fabric. This is done using cam draft or chain draft (CD) for cam and dobby shedding. In jacquard shedding, every warp end is controlled individually. CD diagram shows the order of lifting the harnesses and therefore the warp yams since each warp end is attached to a harness.
In CD diagram, the columns represent the harnesses and the rows represent the picks. The picks are numbered from bottom to top as in the case of unit cell; therefore, the heights of the unit cell and the CD are equal. Similarly, the width of CD and the height of DID are equal since they both show the harnesses. To indicate that a harness is lifted during insertion of a pick, the corresponding square in the CD matrix is filled or marked with an "X" as shown in figure. Conversely, a blank square means that the harness is lowered during the insertion of that particular weft. In the figure, harness 1 and harness 4 is lifted during the insertion of the first pick.

 

n practice Design, DID, & CD are combined together as shown in figure.

Such an organization of weave diagram, DID, reed plan and CD gives most of the information for the design and manufacturing of the fabric. The only information missing from this diagram is the selvages. When specifying a fabric, the specifications for the entire warp should be given, including selvages. The DID diagram and reed plan for selvages are constructed similar to the body of the fabric.