What is the principle of the sewing machine?
Two threads: one in the needle and fed from the top, the other in the bobbin below and fed from the same place.
The shuttle mechanism grips the upper thread, pulls it out of the needle, thereby making a loop that wraps around the lower thread; the mechanism, pushing the fabric forward, changes where the needle enters and forms a stitch.
Two threads: one in the needle and fed from the top, the other in the bobbin below and fed from the same place.
The shuttle mechanism grips the upper thread, pulls it out of the needle, thereby making a loop that wraps around the lower thread; the mechanism, pushing the fabric forward, changes where the needle enters and forms a stitch.