The first step is to optimize the differential feed ratio. Appropriately increase the feeding amount of the front feed dog while reducing that of the rear feed dog. This effectively prevents the fabric from being overstretched during sewing and ensures flat, even seams.
Next, fine-tune the needle bar swing amplitude according to the fabric characteristics. In most cases, reducing the swing range helps stabilize stitch formation. At the same time, lower the presser foot pressure to avoid compressing or stretching the elastic structure of the fabric.
Selecting the proper needle type—such as a ballpoint needle—and specialized stretch sewing thread is essential. These choices significantly reduce the risk of thread breakage or fabric snagging.
Additionally, check that the bobbin thread tension is properly adjusted. Excessively tight lower thread tension can result in stiff seams, negatively affecting the fabric’s ability to recover its elasticity.