It's a well-known theory: Sewing factories spend 80 per- cent of their time handling product vs. 20 percent of time sewing, pressing or finishing. If the theory holds true, that means there are only six minutes of productive, value-added work in a 30-minute garment. The other 24 minutes are unproductive, spent moving and manipulating material so that the productive work can be carried out. Consider this breakdown of the steps involved in closing of two side seams: 1. Pick up first part, pick up second part and position two parts together at beginning of seam, place to needle. 2. Sew seam in three bursts (three bursts required to reposition fabric as one sews along the seam). 3. Reposition two pieces together for second seam, place to needle. 4. Sew seam in three bursts (again three bursts to allow for repositioning as one sews). 5. Fold, set aside and book work. It's a very simple operation, but immediately one sees that the only productive part is the actual sewing, not the repositioning during the seam, not the picking up and placing of the fabrics to the needle, not the folding and setting aside and not the booking of the work. Methods of materials handling can substantially increase the ineffective time. For instance, it is not productive to have employees or supervisors whose responsibility it is to move work around to different parts of the factory. Likewise, folding and unfolding work between operations is not productive. Tying up and untying bundles also is a waste of time. Yet many companies continue to perform these activities, which cost money, and therefore drain profitability. They also take time, thus hampering a company's ability to respond quickly to customer needs and market requirements. If moving work from one workstation to another is unproductive, the storage of work between operations is even worse. No income can be obtained from that work until it is finished and reaches the customer.
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