A Sewing machines stitch as a needle threads top and bobbin yarns together, driven by an electric motor and controlled by a foot pedal. The top and bobbin threads interconnect, forming a continuous loop connecting fabric layers.

The formation of stitches by a sewing machine – how a bobbin catches and knots a thread to form a stitch that holds pieces of fabric together.

Role of the Electric Motor

Sewing Machines have an electric motor that works the machine – it is the main part of a sewing machine. It powers the needle’s up and down movement and the rotation of the bobbin and feed dogs (the toothed metal parts under the needle plate that move the fabric forward). The motor’s speed dictates how fast or slow the needle moves, which in turn affects the stitching speed.

A robust motor ensures the machine operates efficiently without straining or overheating during prolonged use.

Role of the Foot pedal

You have control of the operations by way of the foot pedal. The advantage of this foot pedal is that both hands are free to manipulate and move the fabric.

The foot pedal of your sewing machine controls the motor speed. The more you press on the foot pedal with your foot, the faster the machine sews. So if you increase the amount of pressure you put on it, the machine will speed up stitching, and if you reduce the pressure on the pedal, the machine stitching will slow the speed of stitching.

How stitches are formed

The upper thread and the bobbin thread should meet precisely in the middle of the fabric layers for perfect stitching.

The top thread is threaded on the sewing machine through various tension disks, guides, and the needle’s eye. The bobbin thread is housed in the bobbin case below the needle plate. Now both of them should interconnect on the fabric.

When you start sewing, the needle carrying the top thread descends through the fabric into the bobbin area. A rotating hook or shuttle grabs the top thread as the needle descends and loops it around the bobbin thread.This looping action intertwines the top thread with the bobbin thread, creating what’s known as a ‘lock stitch’. As the needle retracts, it pulls a small loop of the bobbin thread up through the fabric, securing the stitch.

This process repeats with each needle stroke, forming a continuous line of stitches that securely joins the fabric pieces.

Since the first sewing machine was invented, there have been many different types of sewing machines with different functions and capabilities. But the primary use of a sewing machine remains the same – to replace hand sewing efficiently.

The working of a sewing machine varies according to its type and functionality.

Workings of sewing machines based on different types

Sewing Machines can be categorized into 4 basic kinds according to their operations.

Manual sewing machine, Mechanical sewing machine, Electronic sewing machine and computerized sewing machine.

How does a Manual sewing machine work

Manual sewing machine, the most fundamental kind, operates using a treadle. These machines, often classified as vintage, are cherished by their owners. Many are now retrofitting them with electric motors. This modification allows for the retention of the old-fashioned, robust workhorses from the past, while enabling efficient and speedy operation.

It is physically taxing to operate a manual sewing machine for a long time, if the motor is not there. 

Mechanical sewing machine – how it works

Mechanical sewing machine, known for its ease of operation, is the type most commonly purchased for home use. Its distinctive features include knobs and dials for adjusting stitch length and tension. Equipped mostly with buttonhole stitching, utility stitches, and a few decorative options, this machine stands out for its user-friendly interface and versatility.

Workings of Electronic sewing machine

Electronic sewing machines are more of an automated version of mechanical sewing machines with simple buttons and even LCD screens. They are mostly automated with stitch lengths and widths, which can be set automatically. They will have convenient features like an automatic one-step buttonhole and different overlock stitches.

Computerized sewing machine operations

Computerized sewing machine operates with advanced technology. It is capable of downloading patterns, memorizing operations, and seamlessly synchronizing speed with needle functions for precise stitching. Different sewing operations are done with perfect coordination without you bothering your head about it. They have touch screens and USB ports to input sewing patterns and embroidery designs.

Most of the work on a computerised sewing machine is done automatically, and sewing is all the more joyous because of the smooth operations. And all this functionalities comes with a heavy price tag, of course.

According to the functionality, there are sewing machines that work in different ways. They are Sergers, Embroidery sewing machine, and Industrial sewing machine.

Overlocker or Serger working

Sergers or overlockers are basically used to finish seam edges. Overlockers typically use three or four threads simultaneously, though some models can use up to eight. They often have two needles, allowing them to create stronger, more complex stitches.The combination of multiple threads, loopers, and needles allows the overlocker to create overlock stitches.

The serger finishes the seams in one go along with the seam stitching and cutting the seams.

Checkout the post on serger to know whether you need to buy a serger or not.

Embroidery machine operations

Embroidery machines use special technology to copy complicated designs onto fabric without needing much help from a person. The machine reads the digital design file and starts the embroidery process. The needle moves up and down, stitching the design onto the fabric. The hoop moves the fabric in all directions under the needle, guided by the machine to follow the pattern of the design. The working of these machines create detailed and intricate embroidery designs and monograms.

Difference of operations of Industrial sewing machine from normal sewing machine

Many industrial machines are specialized for a specific sewing task, such as buttonholing, hemming, or attaching zippers. This specialization allows for greater efficiency and quality in that particular task. These machines typically have a more powerful motor compared to home sewing machines. This allows them to maintain high speeds and sew through thick or tough materials without straining the motor.

What your sewing machine manual says.

To know more about the inner mechanisms and the working of your particular sewing machine model, take up the sewing machine manual which comes with it and read it thoroughly, cover to cover. This is the bible you should always have at hand because everything related to your particular sewing machine is mentioned in this.

Checkout this post where you can download the sewing machine manual and print it out if you have not got the manual.

Some more tips for beginners on using the sewing machine can be found here.

What is needed for your sewing machine to work properly?

Different parts of your sewing machine and the pressure feet and other accessories you have got with the machine, all play important role in how your machine works.

This post will give more details on the sewing machine parts and the pressure feet. Another post that may interest you is the different sewing tools you will need. Not all of them at the same time, but for specific purposes, you may need to buy some of them.  

Thread

Good quality thread is a necessity, not an option, for the optimal working of your sewing machine. Checkout this post on the best thread to use with a sewing machine for more details on this. Suffice to say different types of fabrics call for different types of sewing threads. A basic knowledge of this is necessary for smooth sewing.

Needle

You also must know that sewing needles are not made equal. There are different types of sewing needles available for different types of sewing/fabric.

Checkout the post for more details on which needle to use with your sewing for more details on this. You should also know how to replace the needle properly. All the experts replace their needles after 6-8 hours of sewing with it. They do not want bad needle to destroy their sewing.

Checkout this post on the correct order of threading your sewing machine; this is a very important element in correctly operating the sewing machine without problems.

Most of the problems when working the sewing machine can be solved by correctly threading the machine. One misstep and your sewing will go all awry. Ensure that when you are threading the machine, the presser foot is raised and the needle is in the highest position.

Bobbins

Checkout the sewing machine manual on how to put the bobbin thread case in your particular machine. Winding the bobbin also will be different depending on the type of bobbin case. It is important to never ever hurry when winding the bobbin. Go at a steady and medium speed for good winding.

Insert the bobbin in the case (drop in or front loading /push type) according to the machine. Take out the bobbin thread through the gap as per the directions.

Move the hand wheel towards you gently. This will bring up the bobbin thread to the pressure feet area. Take this thread to the back of the machine along with the needle top thread before you keep the fabric under the pressure feet to start stitching.

What happens when you start to sew with your sewing machine

Turn the handle (balance wheel) towards you to place the needle inside the fabric and start giving pressure on the foot pedal. Increase the pressure slowly.

Use both hands to gently guide the fabric.

Your sewing machine manual will have an illustration of the different types of stitches available in your machine. It is a good idea to make a sampler of these stitches and keep so that you have a ready reckoner when you want to make some decorative stitches. Most home machines have them displayed on the panel.

Tension

This is the balance between the upper thread and the bobbin thread. If one is off the whole stitching looks bad.

You can check the tension of your machine by stitching a straight line with different coloured threads in the bobbin and the top thread .

If the bobbin thread shows on the top of the fabric or the top thread show on the back of the fabric it means that the tension is off on your sewing machine.

• If the needle thread shows under the fabric tension on the bobbin it means that the top thread is too tight or that on the needle thread is too loose, so tighten the needle thread tension.
• If the bobbin thread shows on the surface (top) of the fabric, it means needle thread is too tight, or that on the bobbin thread is too loose, loosen the needle thread tension.

If the sewing machine shows up any problems along the way consult your sewing machine manual first or you may find some tips here on the frequently asked questions and their answers on the common sewing machine problems. If the inner hardware is damaged so that your sewing machine stops altogether, checkout this sewing machine hardware repair guide.

A proper sewing machine maintenance is of utmost importance, ofcourse. Checkout this post on the best way to do (steps) the sewing machine maintenance.