Methods of marker planning

The purpose of marker planning is to determine the most efficient combination of sizes and shades for each order and to produce the best fabric yield and equipment utilization. One garments cutting order may require several markers to achieve optimum efficiency of marker.
A marker is made for a specific style, fabric, and number of sizes. The length of the marker determines the length of the lay that will be spread. Completed markers are sent to the cutting room electronically or in hard copy for the spreading and cutting processes.

1. Manually produced marker
Manually produced markers may be created by arranging full-size pattern pieces on marker paper or directly on the top ply of fabric in a spread. Pattern pieces are traced using a pencil or tailor’s chalk. Manual methods of marker making are time-consuming and require a great deal of space. Full-size pattern pieces must be manipulated, adjusted, and readjusted on normal fabric widths by moving around until a satisfactory plan is obtained.

Manually made markers are also subject to errors and inconsistencies that may occur in grain variations, poor line definition, placement and alignment of pieces, and omission of pieces. Accuracy of a manually made marker depends on the skill of the individual who laid out the marker and traced it.

After completion of marker planning, it is necessary to draw on paper as more commonly a paper marker is used for cutting. Multiple copies of paper marker are normally needed. These copies can either be made when the marker plan is first drawn, or the master marker can be reproduced as needed by a variety of methods. Such as;
  1. Carbon Duplicating : Carbon duplicating method is used when small numbers of copies are to be made as the original is drawn. Double sided carbon paper or special type of paper can be used. In this method, six to eight copies can be made without too great a deterioration in the fineness of the line.
  2. Spirit Duplicating : In Spirit Duplicating or hectograph carbon system, the master marker is drawn on the paper with the layer of special hectograph paper underneath it. This paper transfers a blue line on the back of the master as it is drawn. The master marker is then used to make one copy at a time in a duplicating machine. The machine uses alcohol to wet a plain white paper which is then passed with the master marker between two rollers transferring lines onto the copy.
  3. Diazo photographic method : The diazo photographic method makes as many copies of the markers are needed, one at time, following the drawing of a master marker. The master marker and light-sensitive paper are passed under high intensity of ultraviolet light and the light –sensitive paper is developed using ammonia vapor. The lines and other markings on the master marker prevent exposure to light sensitive paper which forms the copy; when developed the lines remain visible.
These copying methods were widely used in the 1970s, but have been steadily overtaken by the popularity by computerized plotting. After computerized marker planning, markers are plotted out as a required. This procedure has proved far more versatile and more appropriate for responsive manufacturing than any of these predecessors.

2. Computerized marker
Computerized marker making is more accurate and provides the greatest opportunity for pattern manipulation, marker efficiency, reuse of previously made markers, and shortest response time. Production patterns may be developed on the computer and/or digitized or scanned into the computer. In addition, parameters for markers are entered into the computer from cutting orders. These might include style numbers, size distribution, and fabric width. Technicians manipulate pattern images on computer screens and experiment with various configurations to determine the best material utilization for the marker. Protective devices are built into the programs to ensure grain alignment and prevent overlapping or omission of pieces or other errors. Once markers have been planned and stored, they can be printed or recalled and modified for new cutting orders.

With newer marker-making software, markers can be automatically created. A computer can automatically develop different markers according to the criteria set by a technician. Automated marker making may be used to determine yardage requirements and fabric costs for designs prior to line adoption. Other firms use automated marker making to generate their markers. With automatic marker making, a 50- piece marker can be generated on the computer screen in less than a minute.

Plotting
Plotting is the process of drawing or printing pattern pieces or markers on paper so they can be reviewed or cut. Computer-driven plotters may draw pattern pieces, graded nests of patterns, and/or markers with complete annotation, depending on the needs of the apparel firm. New multi-head jet plotters are much faster and can print variable line density and width, text identification information, and bar codes. Plotting may be the bottleneck in the pre-production processes if a firm runs a lot of copies. Firms using computerized cutters may not need paper markers to guide the cutting process and therefore may only print identification information for bundles.

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