Brother International T-8420B Instruction Manual - English - Page 41

10. TROUBLESHOOTING Problem Possible cause 4 Skipped stitches occur y Is the needle tip bent? Is the needle tip blunt? while sewing If the needle tip is bent or broken, replace the needle. y Is the needle properly installed? If it is incorrect, install the needle correctly. y Is the machine properly threaded? If it is incorrect, thread the thread correctly. y Is the presser foot pressure too weak? Adjust the presser foot pressure. y Is the needle too thin? Replace the needle with a needle that is one rank thicker. y Is the presser foot too high? Adjust the height of the presser foot. y Is the thread take-up spring too weak? Adjust the tension of the thread take-up spring. y Is the thread take-up amount too large? 2945M Adjust the thread take-up amount. 5 Skipped stitches at sewing y Is the thread take-up spring tension too strong? start Reduce the tension of the thread take-up spring. Thread unravelling at y Is the thread take-up spring operating range too large? sewing start Raise the position of the stopper. y Is the thread take-up at its highest position at the sewing start? Set the thread take-up to its highest position at the sewing start. y Is the length of the upper thread trailing from the needle hole too short? Pull about 50 mm of thread through the needle hole at the sewing start. y Is the needle too wide? Try using a needle with a count that is one lower than the current needle. y If sewing light or medium-weight materials, is a presser foot with slots on the underside or grooved feed dog being used? Use a presser foot without slots. Use a feed dog without grooves. Page 14 16-20 26 * * 27 * * 19 20 Grooves Slot 2946M 2944M 35 T-8420B, 8450B, 8720B, 8750B