Just like cars, the basic principles of most sewing machines are the same. The core of the car is the internal combustion engine, the Hat Ironing Machine, and the core of the sewing machine is the stitching system. The loop stitching method is very different from ordinary hand sewing. In the simplest form of hand stitching, the seamstress attaches a thread through the eyelet at the end of the needle, then passes the needle and thread completely through the two pieces of fabric, from one side to the other and back again. This way, the needle drives the thread in and out of the fabric, stitching them together.
While this is very easy to do by hand, it is extremely difficult to pull with a machine. The machine needs to release the needle on one side of the fabric and grab it again instantly on the other side. It then entails pulling all the loose threads out of the fabric, reversing the direction of the needle, and repeating all steps in the opposite direction. The process was too complicated for a simple machine to be practical, and even by hand it only worked well with shorter threads.
Instead, a sewing machine simply passes the needle partially through the fabric. On the needle, the eye of the needle is just behind the point, not at the end of the needle. The needle is attached to the needle bar, which is pulled up and down by a motor through a series of gears and cams (more on that later).
As the tip of the needle passes through the fabric, it pulls a small loop