PENGARUH KETEGANGAN (TENSION) BENANG DAN KERAPATAN JAHITAN TERHADAP KERUTAN DAN KEKUATAN JAHITAN

In the sewing process, thread tension is one of the key factor. It is important to adjust the thread tension correctly to achieve a balanced stitch and avoid defects such as skipped stitches, uneven stitch, or puckering. Stitch density (stich per inch) affect the quality of the stitch. In this study, an experiment was conducted to see the effect of upper thread tension, lower thread and stitch density on stitch strength and stitch quality, especially seen from puckering on a single needle lockstitch machine. Each factor was varied for 3 levels, there were 190mN, 220mN, 250mN for upper thread tension; 220mN, 270mN, and 320mN for lower thread tension and 9spi, 11spi, 13spi for stitch density. Experiments were carried out with all combinations and 3 times replication. The technical responses assessed were the pucker value and strength stitch. Only the upper thread tension (x1) affected the pucker and the stitch density (x3) affected the stitch strength. Combination of x1-1: Upper Thread Tension 190mN, x2-3: Lower Thread Tension 320 mN, x3-3: Stitch density 13 spi would produce best pucker value of 4.00 and best stitch strength of 348.67mN.