Sunday, 14 October 2007
Processes involved in a cutting room
1. The planning, drawing and reproduction of the marker
2. The spreading of fabric to form a lay
3. The cutting of the fabric
1. The planning, drawing and reproduction of the marker:
It has three parts:
1. Marker Planning
It is the placement of the pattern pieces:
1. To meet technical requirements
2. To economise material
2. Marker drawing
It is marking the oulines of the pattern on the marker by pencil, chalk or some autometic method.
3. Reproduction of the marker
It is dublicating the original marker in required quantity for
a. To reduce the time
b. reduce the cost of repeatedly marking in patterns
Marker planning is important because when the cutting room cuts cloth, it spends around half of the company's turnover. Therefore any reduction in the amount of cloth used per garment will lead to a increased profit.
The aim of the marker planning is to try a number of pattern placements, selecting the one which gives the shortest marker.
Constraints in the work of marker planning
1. Nature of the fabric
2. Desired results in the finished garment
3. Requirements of quality in cutting
4. requirements of production planning
1. Nature of the fabric
a. Pattern alighment in relation to the grain lines
It is the direction in which a fabric is woven (lengthwise grain or warp, crosswise grain or weft)
Lenth Grain (warp)- Yarns parallel with the selvedge and at right angle to the cross grain. This is the strongest grain and drapes best when perpendicular to the floor.
Cross Grain (Weft)- Yarn woven across the fabric from selvedge to selvedge. It is the filling yarn of woven fabric. Cross grain yields to tension.
Bias- A slanting line or diagonal line cut or sewn across the weave of the cloth.
True Bias (45o angle)
The angle line that intersects with the length and cross grains at a 45 degree angle. True bias has a maximum give and stretchability, easily conforming to the figures' contours.
The pattern must be laid down within the stated rules, f0r grain lines. If this is not followed then the finished garment will not hang and drape correctly when worn.
Rules for conforming to the grain lines
1. The grain line should lie either parallel to line of warp or weft and not in between
2. For bias cutting, the grain lines will normally be at 45 degrees to the warp.
The designer or pattern cutter may define a tolerance which allows the marker planner to swing the grain line a small amount from the parallel
b. Symmetry or asymmetry
Symmetrical or Either way fabrics: Most fabrics can be turned around and retain the same appearance. These are known as "either way" or "symmetrical " fabrics
Asymmetrical or oneway-eitherway fabrics
These are those fabrics, whose ply, if turned around, does not retain the same appearance. However, as long as the pattern pieces of an individual garment all lie in the same direction, which direction they lie does not mattern.
One way only fabrics
This applies to fabrics with a design object which can only be used one way up, eg. velvet.
Here the marker must ensure that the top ends of the pattern pieces all face the same way
c. Design Characteristics:
E.g. if a vertical stripe does'nt show a complete mirror image repeat, the right and left side fo the garment may be designed to be mirror images of each other. In this case a marker is planned which uses a half set of patterns, and the required effect is created in the spreading of the fabric which places pairs of plies face to face.