Last updated on August 21st, 2023 at 11:47 pm
To cut a sample garment, the pattern components have to be economically arranged according to their grain lines and the pile direction of the fabric which is to be cut. The regular form of this arrangement is a rectangle width the short side equal to the net width of the fabric and the long side the length required to contain the pattern components. The drawing of this arrangement and when starting to prepare markers, there are a number of procedures which have to be followed. This starts by determining the net width of the cloth to be cut, which can be easily done but there are some practical considerations involved.
Principles of Marker Planning
There are no fixed rules for the manual planning of cutting markers because the process relies on the perceptual sense of the planner and the ability to see the best interlocking combination of the pattern components. Nevertheless, there are a number of principles which can be applied.Before starting to plan the marker there are some preparatory procedures to perform:
- The pattern set should be checked to ascertain that it contains the correct number of components for the material which is to be cut.
- If the marker is for open cloth, the pattern set should be verified for correct pairing.
- Each component must be clearly marked with grain lines and direction indicators.
- Direction indicators should be checked against the fabric itself.
- Net width has to be established.
- It would help if the main matching points for checked materials are marked on the relevant pattern components.
- This is also applies to symmetry requirements for checked and striped materials.
When these procedures have been completed the planner or cutter can start the actual planning of the marker, incorporating some or all of the following guidelines:
- If the marker is being planned on marker paper, the first stage is to mark the net width for the estimated length and a starting line at one end. When the marker is being planned directly on the cloth, one end should be ripped across the weft line so as to show whether the cloth is lying straight or otherwise.
- The largest components should be positioned first and where possible the smaller parts are fitted into the remaining spaces.
- Similarly the curved lines should be interlocked when possible.
- The same principle applies to the positioning of angled and straight section which have corresponding forms.
- When there is a permissible amount of tilt from the grain line, care should be taken that two seams which are to be joined are tilted by the seam amount.
- The garment cannot be cut precisely if interlocked parts, especially curved sections, are butted too closely together.
- A tight marker is characterized by the small amounts of ‘daylight’ showing between the components.
Computer Aided Marker Planning
CAD systems are widely used in sample rooms when large number of new sample markers have to be produced continuously. Most of these systems have two alternative modes of operation and the choice between them is dictated by the amount of time available for planning and the accessibility of the system during the regular working day. Before starting by plan either mode, a number of constraints have to be input to the system and these include net width, pile direction, distance between components and the permissible amount of tilt. In addition, the matching points for checked materials also have to be input when necessary. The two modes of operation are interactive and automatic:
This is a two-way electronic communication function between the planner and the system which enables the operator to plan marks with the aid of a computer. During the planning process the system automatically applies the relevant constraints and also indicates to the planner the length of the marker at any given stage. As the system controls all the important details, the planner can concentrate on efficient positioning and reiterations.
When using this mode, another constraint has to be input: the maximum permissible length of the particular marker to be planned. The system plans the markers without any manual intervention and automatically rejects markers which exceed the permissible length. This length is an estimate based on experience and can sometimes lead to the excess usage of materials, but if marker production is more important than a little wastage, the waste has to be accepted. Another benefit of the automatic mode is that markers can be planned overnight without operators being present, thus freeing the system and staff for other productive purpose during the regular working day.