Marker efficiency

Marker efficiency is determined by fabric utilization, the percentage of the total fabric that is actually used in garment parts. The area not used in garment parts is waste.

Marker efficiency

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Area of Pattern

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100
Area of Marker

Marker efficiency depends on how tightly the pattern pieces fit together within the marker. The total surface area of the pattern pieces is compared to the total area of the marker to calculate the percentage of fabric that is used. This is determined automatically by marker-making software. If marker-making technology is not available, the area of each pattern piece may be determined by a planimeter a mechanical device that calculates the surface area as the outline of the pattern is traced. Factors that affect marker efficiency are fabric characteristics, shapes of pattern pieces, and grain requirements. Marker efficiency depends on following;
  1. Fabric Characteristics
  2. Character of pattern piece
  3. Grain orientation
  4. Fabric utilization standard
1. Fabric Characteristics
Fabric characteristics that affect utilization include differences in face and back, lengthwise directionality, crosswise symmetry need for matching the fabric design, length of design repeat, and fabric width. These fabric characteristics frequently limit the arrangement of pattern pieces. Matching fabric designs requires special marker preparation and extra piece goods. Stripe or plaid lines must be indicated on pattern pieces and markers for accurate alignment and matching to corresponding pieces. The greater the length between repeats increases the potential for fabric waste.

a) Difference in the face and back
Placement of fabric face is a major factor in planning marker and spreading fabric. Some fabrics have very apparent face such as prints, jersey knit, pile weaves. Other fabrics have less distinctive face because of unbalance weaves or finishes applied only to the face. Fabrics with subtle difference in face and back accidentally reversed during spreading and assembly, resulting in hundreds of second quality goods.

b) Difference in lengthwise symmetry
The fabric, which is different in structure or appearance in lengthwise direction when fabric is turned 180 degrees. Fabrics having this character are called directional or one-way design. Following the causes of directionality
  • Pile fabric having loop cut or uncut
  • Printed or woven design such as flowers, trees, image of people or animal and some plaids.
  • Fabric nap, loop formation as well as finished applied frequently have lengthwise directionality.
c) Difference in crosswise symmetry
The fabric, which is different in structure or appearance in width wise direction when viewed with warp yarns vertical, fabrics have lake a mirror image from right to left. Such fabric is called crosswise asymmetric.

d) Need to match design
The scale of fabric design and matching is require by customer are major factors in fabric utilization. Large-scale design with prominent figure, weather floral, plaid or stripe usually looks better when matched. Customer may require:
  • No matching
  • Single garment match
  • All garment match.
Large repeat creates excessive waste and are very costly if quality standard required matching. As the design increases in scale, fabric utilization declines because of the necessity of the matching the repeat.

e) Width of the fabric
Different fabric width is available in market. Wider fabric width is economical both fabric production and utilization. Knitted fabric may be used in tubular form. Tubes may be knitted in the specified circular dimensions needed to produce a specific garment size such as the body or the cuff and neck.

2. Characteristics of Pattern Pieces
Characteristics of pattern pieces may limit fabric utilization. Generally the fabric utilization percentage increases when a variety of garment sizes are used in the same marker and when the marker contains both large and small pieces. Smaller pieces can often be nested with larger pieces. The shape of the pattern pieces determine how close they can be fit together (interlock). Irregular shaped pieces are difficult to fit together with other pieces. Placement of large pattern pieces is less flexible and often dictates the placement of other pieces.

Patterns are sometimes modified to increase fabric utilization, although modification may not always be feasible. The following pattern adjustments may be used to improve fabric utilization:
  • Splitting pattern pieces and creating a seam
  • Rounding or slanting corners
  • Reducing seam allowances and/or hem width
  • Adjusting pattern dimensions without noticeable change to fit and style
  • Adjusting grain lines for hidden garment parts
  • Modifying grain lines specified by the designer
Both marker and cutting efficiency may be improved by using a continues line between pattern pieces. For example, several waistband in juxtaposition could share a common cutting line and be cut with one pass with a cutting knife a common line needs to be a smooth, clean cutting line for both pieces so inaccuracies do not occur.

3. Grain Orientation
Grain line markings determine the placement of the pattern relative to the warp yarns in woven’s or wales in knit fabrics. Pattern pieces with a similar grain orientation, if grouped together on the marker, generally produce batter utilization. Combining several bias pieces and straight grain pieces may not fit together as well and create more fabric waste. Markers usually have good utilization when all pattern pieces are on the bias or all pieces are cut on straight grain.

The firm’s standards for grain tolerance may also affect marker efficiency. Tilting specific pattern pieces 1 or 2% may not be noticeable, and it may increase fabric utilization noticeably. This practice can impact the fit and drape of the finished garment but it may not be noticeable to the untrained eye. Computer marker- making programs will lock in the grain orientation of each piece unless an override function is used to adjust them. This can be done on a piece-by-piece basis.

4. Fabric Utilization Standard
Factories often establish fabric utilization standards. Farms producing basics may strive for 90 to 97% utilization, while fashion achieve only 80 to 85%. It is important for firms to document and variances from the standards to monitor improvements ct the utilization. Better utilization is normally developed for optimal fabric widths are used consistently and more time is invested in cut planning and manipulating pattern pieces in the markers to reduce waste of materials. Markers for basic styles are used to cut large volumes of and may be kept on file and used repeatedly; thus, the time invested  utilization results in greater savings. 


Marker for fashion styles and Quick Response strategies may be used only limited number of spreads and few ply. Fashion garments are subject changes in styling and materials and tight deadlines that limit the time available to develop efficient markers.

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