Abstract
It is a common understanding that if the needle cuts threads of the material while sewing, the seam has deteriorated appearance, and the more the damage is done, the weaker the seam is.
We have studied the relations between stitching and damage on threads of the material with the slant needle sewing machine and the ordinary sewing machine. The results obtained are as follows :
1) Threads were more damaged by the size # 14 needle than size # 11 one. Also the slant needle sewing machine did more damage to the fabric than the ordinary machine.
2) Negative correlations were found between damage on threads and effectuation of the sewing.
