How does a Sewing Machine Work (Helpful Mechanism Guide)
When technology helped invent the sewing machine it was supposed to make your sewing life a lot simpler, easier and faster to do. Learning how a sewing machine works is a great way to keep your sewing life that way.
How does a Sewing Machine Work: You have two ways to operate a sewing machine. The first way is the simplest as all you do is plug it in, turn the power on and make your stitch and pattern selections. Or the other way is to use a manual sewing machine and use the handwheel or treadle to operate the needle. Either way, you can enjoy your sewing duties a lot more.
Sewing Machine Stitch GIF animation
To learn about the sewing machine and how it works, just continue to read our article. It is filled with the information you need to know to understand the mechanics behind the machine.
Sewing Machine Mechanism 101
How Does a Sewing Machine Stitch
I - The Loop Stitch
Using a sewing machine to stitch your fabrics together is not the same as hand sewing them together. In hand sewing, you are usually using a loop stitch, passing the needle and thread through two fabric pieces to attach them together.
After you tie the thread through the eye of the needle, you pass both trough the fabric pieces and you get your loop stitch. With a sewing machine that is basically impossible to do. What the sewing machine does to compensate for that failure is to only put the thread partway through the fabric.
On a sewing machine the eye of the needle is down towards the pointed end. Once you thread the needle, you use the needle bar to attach the needle to the sewing machine. Once you turn on the power, the needle bar goes up and down putting the thread through the fabric.
The needle bar is powered by a motor which uses a series of gears and cams to make sure all the moving parts move as they are supposed to. As the point of the needle passes through the fabric it pulls the loop to one side of the fabric.
Then a mechanism pulls the loop around or through another piece of thread or another loop. The mechanism is underneath the fabric. There are a variety of loop stitches and each one is handled differently by the machine.
II - The Chain Stitch
The sewing machine handles this type of stitch with ease. To make it work, the fabric is sitting on a metal plate and is held down by the presser foot. At the beginning or every stitch, the sewing machine needle creates a loop.
Once that is done, the looper mechanism, moving in sync with the sewing machine needle grabs the loop before the needle moves up. After the needle is out of the fabric, the feed dog part moves the fabric forward.
Next, the when the needle goes down to start a new loop, it goes through the middle of the previous one. The looper mechanism then grabs that loop and wraps it around the next loop that is created by the needle.
It is called a chain stitch because the loops are held together like a chain is. One link holding the next in place.
III - The Lock Stitch
This is a sturdier stitch which is found on most sewing machines no matter their type. With the lock stitch, it operates much the same way as the chain stitch. But instead of chaining it together like the chain stitch, your sewing machine uses the bobbin to add more thread which is then used to lock the stitch in place.
The most important parts of the lock stitch are the bobbin assembly and the shuttle hook. The bobbin brings thread underneath the fabric and dispenses its thread through the power of the motor.
The needle pulls the loop through the fabric and the feed dog moves that fabric like the chain stitch. The stitch is then locked to the bobbin thread and not to its fellow loops that come after it.
When the needle creates the loop, the shuttle hook grabs the loop and pulls the loop around the thread coming from the bobbin. This method gives you a very strong stitch that should last you a while.
Sewing Machine Working Principle
The working principle has a variety of ways to make the sewing machine operate. Yet, while there are a variety of sewing machines, the working principle remains the same. The manual and electric versions all use manual or electric power to move the gears and came in a coordinated effort so that the needle moves up and down putting a thread into your fabric.
The different parts of each style of sewing machine then do the job they were designed to do to make sure you get the best stitch [possible or the one you want to use.
For example, the manual foot-powered style of sewing machine uses a treadle and belts to move the different gears and move the needle and the feed dog, bobbin feature as well as the shuttle hook and the other vital sewing machine parts.
The handwheel models do the same thing except that they do not have a treadle for you to use. All the parts of the sewing machine are moved by hand and are constructed in basically the same manner with belts and gears to move those important moving parts.
All the electric models do is use electric power to do the same job. These versions of the sewing machine take away from your manual effort and save you a lot of energy. In all models, there should be a rotating cam shaft that handles all the movement of the parts placed after it.
The shaft is turned by the treadle, hand wheel or the electric motor. In a nutshell, that is the working principle of the sewing machine.
How Does a Sewing Machine Work Step by Step
We will only do a step by step description for the electric sewing machine. The foot and hand-operated models work in the same fashion but may have fewer parts and no motor. The step by step instructions are basically the same for all models with a few modifications.
Here are some initial steps to take:
I - Setup
First, find the power switch. They are not always in the same place but usually, they are located on the right side of the machine.
Second, Place your spool of thread on the spool pin.
Third, bring your thread from the spool through the thread guide. This is a little piece on the top of the machine not to far from the spool pin.
Fourth, to the right of the spool pin is the bobbin winder and bobbin winder stopper. Make sure your bobbin is in place and the thread attaches to it for rewinding.
Fifth, if your machine has one, turn the stitch adjustment dial to the type of stitch you want to use.
Sixth, take your thread through the thread take-up lever. This is usually on the left side of the machine.
Seventh, the next thing you need to do is adjust the thread tension dial to get the tension you need on your thread and for the sewing machine to work properly.
Eighth, thread the needle and get the thread to al the other parts on your sewing machine.
Ninth, set up your underneath bobbin to make sure you have the thread you need for your stitch selection.
Tenth, turn the machine on.
II - Operation
- Place your sewing machine in a strong, stable and sturdy cabinet or table. Make sure you are comfortable and the chair fits next to the cabinet properly giving you good legroom.
- Install your needle. Usually needles can be inserted only one way. There is a flat side on the needle to help you get it right.
- Next, wind and insert your bobbin. This gives you your underneath thread for your best stitches.
- Place the spool of thread on the spool pin and thread the machine. If the machine is already threaded, skip this step unless you are changing colors.
- Next thread your needle and get your bobbin thread out from its position underneath the bobbin cover.
- Plugin your sewing machine and turn it on. Start your sewing project and enjoy your private time doing your hobby or necessary repairs.
Not every machine will be as simple as this to use. There are many models with lots of bells and whistles you need to attend to before you get your sewing project under way.
The key to your successful operation will be to make sure you read your instruction manual first. That way you will get all the details you need to make sure your sewing machine is prepared just right.
How do Sewing Machine Bobbins Work
First, you need to know what a bobbin is before you can understand how it works. What the bobbin does is provide you with the underneath thread when you do your sewing. You can use the same color of thread on your bobbin as you have on your spool or change the color for special effects or if the thread will not be seen.
Second, the bobbin can be made from a variety of construction materials. They can be made of stainless steel, other metals or plastic and they run about 1 inch in diameter. That is usually there standard size.
The size of the bobbin can be about 1/4 to 1/2 of an inch depending on the brand of your sewing machine and its age. The ready to use bobbins come with thread already wrapped around its spool.
Third, the bobbin needs to be placed on the bobbin winder after you thread a little thread through the bobbin’s top. Once that is done, place the bobbin on the winder and put the winder stopper in place against the thread.
Wind the thread a few times around the bobbin before you start sewing. When that is done you should be able to sew to your heart’s content. If you have an underneath bobbin holder, drop your bobbin in there and pull the thread out a few inches. Once that is done, you can begin sewing with ease.
The Inner Works of a Sewing Machine
The cover does hide a lot of the secrets that make modern sewing machines run.Once you take it off, you will see a lot of gears, pulleys, cranks, belts and more lying underneath and out of your sight.
All of these parts are run by one electric motor which is attached to a drive belt. The drive belt moves the drive wheel which in turn rotates the upper drive shaft. From there, the upper drive shat moves a lot of mechanical parts attached to it.
One of those moving parts is the crank. The crank’s job is to move the needle up and down so you can get your sewing done in time. A belt connects the upper and lower drive shafts together making sure the lower drive shaft moves those mechanical parts connected to it.
Because these two drive shafts are connected the needle and the shuttle move in unison.
Some Final Words
Knowing how the sewing machine works can be a fascinating subject. Besides knowing how the machine works, you also get a boost in repair work if anything goes wrong. You can find the problem quickly and know how to repair it without going t a technician.
This knowledge should make your sewing go faster while saving you a little money. The good thing about knowing ow your sewing machine works, you see how everything works together to make sure your sewing time is better than it ever was.
Of course, more complicated machines will have a lot more parts to know about but only because they have quite a few more features built into them.
