Sewing machine technology is advancing, with many models becoming more complex and full of fancy features.
Yet at the heart of every sewing machine is the same old mechanism that produces the stitches that combine to seam fabric together.
This brief primer on the workings of sewing machines is good information for all sewists to give them a basic idea of how the magic happens and how every machine, regardless of the fancy features, is basically the same.
Sewing Machine Parts Are Basically the Same
Though the earliest sewing machines were vastly different from today’s machines, they all still work essentially the same way.
A motor on the machine is connected to a drive wheel, the drive wheel moves the drive shaft, and then the drive shaft moves the needle, the thread arm, the linkage that controls the feed dogs, and other mechanical parts on the sewing machine.
Whether the sewing machine mechanism works by hand or foot levers as early machines did or via an electric motor activated by a foot pedal like modern machines, the mechanism is the same.
How Are Stitches Actually Created?
But how do sewing machines actually stitch?
Stitches are made when the drive shaft raises and lowers the needle bar so a loop of thread gets pushed through the fabric with the needle tip.
While the needle and thread are through the fabric, the bobbin which is being activated by another mechanism on the drive shaft, hooks the thread and loops it with the bobbin thread, creating a single stitch.
As multiple stitches are made, they hold each other together to create a seam.
How Are Stitches Other Than Straight Stitches Made?
Plain straight stitches are the basis of every stitch that every sewing machine makes, but most make a variety of other stitches as well.
How is it done?
Through a variety of movements of the needle and how it interacts with the bobbin, all of which can be accomplished by building a mechanism that moves not only up and down but also side-to-side via the needle bar.
What Is The Role of The Presser Foot?
Also, specialty presser feet contribute to the making of certain stitches when they manipulate the position of the fabric while the needle bar controls the needle and thread.
Today’s computerized sewing machines that can make hundreds of stitches do so through computer programming that directs the mechanical components to control the needle bar and the bobbin hook.
In Summary
Sewing machines, from the earliest models that helped to build modern civilizations to today’s advanced versions that can do incredible things, are amazingly complex yet surprisingly simple all at the same time!