Abstract
When the two pieces of textile fabrics are sewn together on a sewing machine, the mechanical action produces the relative slippage of the lower piece to the upper piece. This has so far been considered as a result of difference in frictional forces between the upper and lower pieces.
From the point of view of mechanical difference in sewing machine, the authors carried out a series of experiments on the slant needle and the vertical needle machines. The results obtained are as follows :
1. When the machine with a needle slanting at 9° is used in sewing, the slippage produced between fabrics is greater. This is due to the slant needle and feed-dog mechanism.
2. The shorter the pitch of a stitch is, the less the degree of slippage is.
3. The larger the frictional force and the stiffness of the material are, the less the degree of slippage is.
