Why Does My Sewing Machine Keeps Knotting?

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Most, if not all, people have experienced a machine-sewn project that they wanted to salvage: a torn shirt hem, a zipper that popped open, or even just the desire to finish sewing up an article of clothing. So fear not. In this piece, we will explore several common causes of machine-sewing errors and teach you how to prevent them from happening again on your next project.

Keep in mind that if you rent a sewing machine, the company most likely will not cover all these issues. You have to have your own machine or be willing to risk making a few mistakes.

Knots are among the most common sewing problems. They take place when two threads get tangled together, usually as you sew around your bobbin case. If a knot forms, press it flat and continue sewing. If the knot is small enough, you might be able to catch it in your seam and continue on.

However, if the knot is too large, you’ll need to cut both threads and start again. Another option is to try threading your bobbin with another strand of thread from a different color so that if you do get a knot, it’s not troublesome.

Another common sewing error is broken threads on a horizontal seam, particularly appearing about one inch from the end of a seam. Many sewers assume that the problem with their horizontal stitching is that they are holding the fabric too tight. Wrong! The good news is that this is easily corrected by switching to a ball-point, or stretch, needle.

In this article, I am going to explain to you how sewing machines keep knotting.

Why Does My Sewing Machine Keep Knotting?

The sewing machine keeps knotting when the thread is too short for the project. It is not clear if this is a problem with an industry standard or if it is just a matter of personal preference, but many sewers swear by making all their stitches at least two inches long. This makes them easier to remove later on, and it allows for more flexibility when you are trying to stretch your seam out and maintain even tension across all of the layers.

Another reason that your machine can keep knotting is when the tension is too loose or tight. You should sew with at least 1/4 inch tension on your machine, which is a very loose setting. This allows you to make more fabric movements as you sew and helps keep your stitches from breaking.

The third reason for a sewing machine to keep knotting is when the thread is too dark or too light in color. Darker colors can cause the machine to overheat because they absorb more light. This problem can be fixed by changing your needle to a ball-point or stretch needle.

If you are having trouble with knots in the bobbin thread, make sure that you take the extra few seconds to make sure that things are super taut and tight as you are sewing. Bobbin tension can be an issue, so check it before each use and make sure that it is how you want it to be.

If you don’t have an identical color thread, then try changing your bobbin thread to a different color. The color difference can cause problems with the tension setting on your machine, and as a result, you get knots in your bobbin.

What Are The Reasons For Knotting In A Sewing Machine?

There are some common causes of knotting in the sewing machine.

  1. Dull needle
  2. Short thread
  3. Thread bunching
  4. Thread tension 
  5. Not clean or old bobbins
  6. Stitching speed
  7. Wrong needle for the thread
  8. Bobbin works in machine improperly
  9. Wrong bobbins for thread
  10. Wrong tension on the machine
  11. Change of stitch pattern
  12. Bobbin tension is too light for fabric thickness
  13. The needle path is improper
  14. Wrong fabric selection.

Dull Needle

A dull needle can be one of the reasons for knots in a sewing machine. Sewing machines require sharp, solid needles to sew through fabrics and threads properly.

A dull needle is when the needle does not cut through the entire fabric and the thread. When the needle does not cut all the way through, it leaves a large loop in the fabric, and this loop causes a knot.

Short Thread

Another reason is that the thread may not be long enough for the project and keeps knotting together when sewing with it due to poor tension settings on the machine. You can solve this by making all stitches at least 2″ long. 

If the thread is too short, it will curl around itself, forming a knot. So make sure to use a long piece of thread when starting stitching again. If a stitch breaks, then you need to make sure that you start the new stitch at least two inches away from the breakpoint.

Thread Bunching

On a sewing machine, thread bunching can also cause knots to form on a sewing machine if you are trying to stitch too quickly or if you start with an incorrect tension setting that is too tight or too light based on fabric weight. 

Improper decisions can cause your sewing machine to keep knotting. The first decision is how much thread you take out of the spool.

Thread Tension 

Another reason is the tension on your sewing machine is set too tight or too loose, causing your thread to tangle.

If you are using a pattern with appliqué, your fabric layers might be thicker than in other projects, which is why the tension should be set lighter. If you are using a different fabric for the top layer of your appliqué and you have set the tension too loose, it will pull the thread out of the bobbin when it gets tangled up in the spool.

Not Clean Or Old Bobbins

If you are sewing and your machine is making a loud clacking noise, this may be another reason why your machine keeps knotting. The problem with the bobbin thread is that it may not be unwrapped properly from the spool, and when you sew you get all sorts of tangles and knots.

Stitching Speed

Another reason might be that you are trying to sew too quickly and this causes the stitches to be uneven. If you are a beginner, you may need to slow down when stitching so that each stitch is the same length.

Sewing machines are designed for speed, which makes them suitable for sewing faster than stitchers. Sewing machines can go up to 3,000 stitches per minute, which is way more than any human could match. 

If you are sewing too slowly, the machine can go into a locked position and cause a mess of knots. Make sure that you are moving your fabric around at a comfortable speed for you when you are sewing.

Wrong Needle For Thread

Another reason is using the wrong needle with your thread or using an old, dull needle that is no longer sharp. A needle should be changed every time you change your thread, and it should be changed more frequently if the thread is dark-colored.

An old and dull needle can cause the thread to knot up when sewing. Change the needle often and make sure that it is brand new.

Bobbin Works In Machine Improperly

The third reason for knots on a sewing machine is that the bobbin is not working properly, either because it has become too hard or too soft. If you are sewing and you hear a noise like a popping sound or a choking sound when sewing, this may be an issue with your bobbin.

The bobbin is supposed to be taut and firm when sewing, and it is also supposed to be slightly larger than the needle. If your bobbin is too soft or too hard, then this can cause issues with the tension on your machine. 

You can fix this by using a new brand of the bobbin. You will not have this issue with a brand new bobbin as it is not hard or soft from being used in the machine many times.

Wrong Bobbins For Thread

Another issue might be that the bobbin is the wrong type for the thread or that you are using a different thread in the machine than what is on your bobbin. If you are using a different color thread on the top of your machine and you have used a dark-colored thread on your bobbin, it can cause issues with binding and knots.

You can fix this by using the correct brand of thread or the correct type of bobbin. 

Wrong Tension On Machine

Another reason is that the tension on your sewing machine is set too tight or too loose. You might think that you have fully wound up your bobbin, but you still have a lot of thread left in it. 

To fix this, turn the tension knob on your sewing machine down and then slowly turn it back up. If you have a hard time turning it back up, then this means that your tension is set too tight.

Change Of Stitch Pattern

Another reason is that you are using a different stitch pattern in your sewing machine than what was originally on the pattern. A different stitch pattern can cause the machine to stop stitching and make many tangles and knots on the sewing machine.

As you sit down to sew, it is best to start with the last stitch you sewed and then work your way back. If you do not know what you have sewn in your fabric, just start with this stitch and work your way back. 

Bobbin Tension Too Light For Fabric Thickness

The bobbin tension is too light for the thickness of the fabric that you are sewing and it causes stress on the thread.

If you are using an overlocker and your thread is too thin, it pulls the thread out of your bobbins when it gets tangled and this creates many tangles and knots.

Needle Path Is Improper

Many of the top issues that cause machine knots on a sewing machine are that the needle path is too thin for the thread or it is not large enough for thicker fabric, making an improper path.

If you have a piece of thicker fabric and you are using a thinner thread, then your needle will not be able to pierce through the layers and this causes it to get caught up in the thread and create many tangles. The needle should be changed often as well if you are sewing with different types of threads.

Wrong Fabric Selection

Another reason is that you are using the wrong type of fabric for the project that you are sewing. When you have to use a different fabric for a project, and your sewing machine keeps getting tangled up in knots, it is because the stitching speed on your machine is different from what was used when you sewed with your other fabric. 

If this is happening with different fabrics, then it may be because your tension on the sewing machine is set too tight. 

The only way for this problem to be solved is by changing the tension setting on the machine.

How To Prevent Sewing Machine Keep Knotting

Here are some tips for preventing sewing machines from knotting.

  1. Use the right needle

Select the needle with a suitable length and width, try to use the needles that are recommended by manufacturers.

  1. Use high-quality threads

Don’t use low-grade, poor-quality threads for sewing, especially for topstitching, cording, and lacing. The high-quality thread will protect your machine from being bothered by knots. So choose the best sewing thread and spool to ensure smooth sewing. 

  1. Keep the tension set correctly

Increase the tension, if you are using too light of a thread, or you are sewing with high-quality thread with a loose weave. When sewing heavier fabrics, such as denim, choose a larger needle.

  1. Choose the right bobbin

If your bobbin is not working properly it can cause many problems in the machine and cause knots to happen. Use new, high-quality bobbins that are the right size for your machine.

  1. Clear away old thread

After you finish sewing, it is best to clear away your old thread in the bobbin case as soon as possible. If you leave the old thread in your bobbin case, then this causes tension problems and sometimes can cause tangles on a sewing machine.

  1. Use the right needle for sewing

If you are sewing thick fabrics, heavier fabrics, or have a lot of seams and corners that are causing more problems, use a size 10/70 needle in your machine.

  1. Store your thread properly

When you finish a piece of fabric, make sure to properly store the spool of thread in a plastic case so it doesn’t get tangled with other threads or fibers. You can also place scotch tape over the end of the spool so it is not unraveling as well.

  1. Use of a thread conditioner

For sewing with high-grade or poor-quality threads, use a thread conditioner to protect your machine. A good example of this is the Brother ST-300P Olfa Sewing Machine Oil with Thread Conditioner. This will help keep your machine working properly without any breaks and tangles that might happen as well. 

  1. Clean the bobbin case and bobbin area after using it

Maintain proper hygiene for your sewing machine by cleaning it regularly with a brush and vacuuming.

  1. Use of sewing machine oil for sewing machines

For all sewing machines. This helps to lubricate the machine’s moving parts. It is best to use a good quality, low latex content thread that has just enough stretch to it, or a polyester thread that has static preventive properties.

Why Is My Sewing Machine Knotting Underneath?

When you are doing sewing, and your sewing machine keeps knotting, try to check if your bobbin is twisted. When the bobbin is twisted, your thread will get tangled on a sewing machine and it will not sew properly.

If this is the case, then stop what you are doing and try to hold onto the thread underneath with one hand as you help turn the top spool manually. If this does not work then it is best to take the bobbin out of the machine and re-thread it correctly.

If you are doing embroidery, try to use a stabilizer on your project. This will help keep the fabric stable so the stitches don’t go into the knots and will not be affected by it.

When you are sewing, it is best to change your tension settings on occasion as well. Always keep in mind that if you have thicker fabric and use thick threads, then your needle should be set more snugly as well.

Use the right needle for your project, too. If you have a lot of thick seams, tight corners and thick fabric then use a size 70/10 needle to prevent any sewing machine from knotting.

Most of the time, when you are breaking or snapping your thread or when you hear “rat-a-tat-tat”, this is a sign that your machine is not threading properly and it needs to be rethreaded. Many times the problem is that the needle threader on your machine has broken off, worn down or just not working properly, causing tangles on a sewing machine. 

If you are having trouble with this on a regular basis, then it is best to have your machine looked at by an expert. If you are trying to thread your machine by hand and it still doesn’t work properly, try to look underneath the needle area and see if there is anything stuck underneath it.

How Do I Stop My Thread From Tangling On My Sewing Machine?

  1. Thread the needle by hand.
  2. Use a ball point needle if your machine has one, or use needles that are designed to be handheld. This is to prevent it from being accidentally sucked into the machine.
  3. Don’t sew over that same area again and continue to change thread when needed, even if you think you are sewed. 
  4. Keep your thread spool on a thread stand and make sure the thread does not touch the floor. 5. Make sure that the needle is not touching any other part of the sewing machine. 
  5. Keep your tension set correctly, too tight or too loose can also cause problems grabbing and pulling at your thread.
  6. Use a stabilizer underneath a piece of fabric to help keep stitches in place as well as to keep them from going into knots as well.

FAQ about Sewing Machine Knotting

How do I stop my thread from knotting?

After your piece of fabric is finished sewing, remove the bobbin from the machine and remove the old thread from your bobbin case so you don’t have to keep having to thread your machine. Wipe out any debris from under the bobbin case, threading area, or other parts of your sewing machine that may be causing tangles. Clean out any excess thread if left in areas around the machine such as a hole in a curved area on the front or back. Unravel your thread from the bobbin case and spin it out to check for any snags or issues with threads. Change the needle, use a heavier needle when your fabric is thick, or for thicker threads, use a size 70/10 needle to prevent tangling. At last, Adjust your tension settings on the sewing machine. If you are having trouble with tangling, then lowering your zigzag stitch settings will help since these stitches use more tension and can cause tangles as well.

Why does my cotton keep knotting?

This is a commonly asked question, and one of the most common causes. Cotton is naturally a delicate fiber and will fray easily in battle with your machine. The most common type of cotton that is used on home sewing machines is what’s known as “quilting” cotton. This is a very fine and smooth yarn that is used specifically for quilts and other types of projects like pillow covers, quilts, wrapping paper, or fabric to name a few.

What to do if the thread gets twisted while stitching?

It happens more than you might think! It’s not always a bad thing though. Most of the time, if you are stitching something with a lot of twists and turns, it can be helpful to use the bobbin on a ballpoint needle. If the thread gets tangled up in that area instead of getting twisted so hard, it will still work properly.

Why is my sewing machine packing thread under?

Usually dropping the needle down into the fabric will cause the thread to get caught on something like a bobbin case or a piece of metal. As long as you keep your tension right or your needle in the right place, this should not happen too often. If you have a place where there is a lot of movement and vibrations, then that can cause it as well.

Why does my top thread keep getting tangled in the bobbin?

If this is happening to you, then it could be because you are doing a faster stitch and the thread can’t keep up. Try lowering the top speed of your machine to help reduce the speed at which you are sewing. Also, try using a heavier needle when you are sewing fabrics that are thicker or that use thicker threads.

What should your sewing machine tension be?

Most sewing machines have a thread tension setting that allows you to change the amount of tension (tension is the amount of pressure that holds your thread in place) that is being used. You will have to adjust or experiment with this on your machine to find the best tension for you. Sewing machines in general should be set somewhere between 2 and 6 on a lighter side, and somewhere between 10 and 12 for a heavy setting.

What causes bird nesting in sewing?

Most of the time, if you are making sure that the bobbin is filled with the right type of thread and you are lowering your needle so it is not going through too far into your fabric, this should not be a problem. If you notice that it just keeps happening, then it may be because there is something stuck or caught in between your needle and the spring on your machine. Also, Try changing out different types of needles as usually different needles will work better with different types or thicknesses of fabric.

Why does my thread keep jamming?

If you are using a machine that has a top loading bobbin, then most of the time there will be a tensioner with a knob on it. Use this knob to lower the tensioner and make sure that the thread is not being pulled too tight and causing the thread to break while you are sewing. Change out your needle if it has been worn out or damaged from use. The wrong type of needle can also cause problems such as tangling or jamming.

Final Thoughts

So to fix all the issues you are facing, you need to check the thread tension and needles, then check for old thread in the bobbin, and make sure the bobbin is not twisted. Then if you still have trouble with your machine keep knotting, it is best to see a professional and see what they have to say about your machine. If all else fails and nothing works as it should, then it may be time to replace your machine or get a new one.


  1. Fixya – It keeps knotting up how do I solve that? Give me help
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  3. Quora – Why is my thread bunching up from the bobbin on my sewing machine?
  4. Quora – Why does thread keep getting jammed up in the underneath the foot part by the bobbin in my sewing machine?
  5. Stackexchange -how can i stop my thread from bunching when using a sewing machine?
  6. Reddit – Please help! The top thread keeps on cutting and knotting on the bottom. I had to change bottom thread and now it won’t work the same and keeps skipping it seems like. I don’t know what I did wrong :



I have been working as a seamstress since I was 12 years old, and I would be happy to teach you what I know. I, along with the rest of my team, investigate numerous sewing, quilting, embroidery, and fabric related how-to guides, and present our findings to you.

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