Interlock Sewing Machine Loose Stitch Solution

Loose stitches during interlock sewing operations are often caused by insufficient bobbin thread tension or improper feed dog height. First, adjust the bobbin thread tension to an appropriate level to ensure the stitches are tightly secured to the fabric; low tension results in loose stitches, while excessive tension may cause thread breakage. Second, check whether the feed dog height meets standard specifications—if it is too high or too low, it can affect the stability of fabric feeding, leading to uneven stitching. Additionally, improper adjustment of the needle bar swing range can worsen the issue and should be corrected based on the overall machine structure. By systematically troubleshooting these factors, stitch tightness can be quickly restored, preventing a decline in sewing efficiency.