nahtverhältnis

Nahtverhältnis is a German term that translates to "seam ratio" or "sewing ratio" in English. It refers to the ratio of the length of the stitches on the underside of a fabric to the length of the stitches on the upperside of a fabric when sewing. This ratio is primarily determined by the thread tension settings of a sewing machine.

A balanced nahtverhältnis occurs when the stitch lengths on both sides are approximately equal, resulting in a clean and durable seam. If the nahtverhältnis is unbalanced, it can lead to various sewing issues. For instance, if the upper thread tension is too tight relative to the lower thread tension, the stitches on the underside will be longer than those on the upperside, potentially causing puckering or skipped stitches on the top. Conversely, if the lower thread tension is too tight, the stitches on the upperside will be shorter, leading to a loopy appearance on the underside of the fabric.

Achieving the correct nahtverhältnis is crucial for producing professional-looking and structurally sound sewn items. Seamstresses and tailors adjust the tension dials on their sewing machines to achieve this balance, often testing on scrap pieces of the same fabric before commencing the actual sewing. Factors such as thread type, fabric weight, and needle size can influence the optimal nahtverhältnis, requiring slight adjustments for different sewing projects.