Sewing Machine Tension Problems And Their Solutions

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Recently I had a bad experience with my sewing machine. I was trying to sew a sweater and the feed dogs were not working right. The fabric kept getting stuck, the stitching was uneven, and it seemed like everything that could go wrong did go wrong.

I realized while troubleshooting that the tension on my sewing machine was incorrectly set. Once I adjusted the tension, everything went back to normal and sewed together well – it looked like my old reliable machine again.

If you have a similar problem, or if you have any questions about sewing machine tension, I hope this blog will help.

Granted my sewing machine was actually in perfect working order before I adjusted the tension, so it’s hard to blame it entirely on the tension. However, my opinion is that improper tension is one of the biggest causes of sewing problems and often goes overlooked. 

Various Tension Problems in a Sewing Machine

In a sewing machine, you can face the following tensions.

  1. Thread tension
  2. The needle bar tension
  3. The spool pinion control (or “speed control”) tension
  4. Bobbin tension
  5. The tension on your backstop screw

Thread tension

The difference in tension between a sewing machine and a tape measure. When you use a sewing machine to sew you need to have the tension correct for the type of thread you are using, the weight of your fabric, and the type of project being sewn.

When I sewed my own sweater I used an all-purpose thread that came pre-cut with two spools. The threads were different sizes but they were all 50 yards long (60″ in length). 

The threads were worked into the fabric at a consistent tension but I think they were too light weight for sewing that thick of a fabric. The nice thing about this thread was that it wasn’t as expensive as a professional quilter’s thread so it saved me some money but I don’t think it performed as well as I had hoped. 

Next time I would use a heavier weight thread and maybe have 2 or 3 spools on hand in case one broke before I got to the end of the seam.

The tension on a zig-zag stitch is different from the type of stitch you would use for a more complicated pattern. I usually sew a straight line across the fabric but I wanted to match the texture so I used a zig-zag stitch. Tension during sewing really shouldn’t be an issue because it’s controlled by how hard or loose you press down on the machine, which is, in turn, controlled by your pressure.

The tension on a straight stitch is different from the tension on a zigzag stitch. When sewing a straight line you need to make sure your zig zag (or any decorative stitch) is consistent in tension. If you’re using a machine that has adjustable tension, make sure it’s set correctly. If you have multiple decorative stitches on your machine, check the settings for each one when switching to make sure all the tensions are equal for all the stitches.

The needle bar tension is set too tight or loose

The tension on the needle bar can also contribute to issues with your sewing machine. If the needle bar tension is too tight, it will pinch or catch the fabric causing stitches to be irregular, bumps in your stitching, ng and uneven seams.

If you’re having problems with your sewing machine, try putting a few drops of oil on the end of your needle before inserting it into the fabric and see if that helps solve your problem.

By lowering the needle bar, you can fix some tension issues. The needle bar tension is usually located just above your presser foot on the right side of your machine. This is usually a small screw or rod and if you turn it one way it will tighten and the other way it will loosen. 

The needle bar tension should be loose enough so that the fabric glides easily under the presser foot but not so loose that it bunches up and isn’t able to keep a straight line.

Lowering the needle bar tension will make your machine sew in a straight line and evenly but it may cause the fabric to catch or catch on the feed dogs. The feed dogs are located in the center of your machine, just above where you would first put your needle into a seam. If they are catching, your tension is probably set too loose.

If you have a metal plate under your needle plate that’s there to protect your needle plate, you may want to raise the plate slightly so it doesn’t interfere with the feed dogs.

The spool pinion control (or “speed control”) tension is set too tight or loose

The tension on your spool pinion control can also have a similar effect. If the spool pinion control is set too tight, it will cause your fabric to bunch up. You’re less likely to notice this problem because it usually happens when you’re sewing and are focused on keeping a straight line. If you do notice that your fabric is bunching up under the presser foot, try loosening the spool pinion control.

Tension issues are the hardest to troubleshoot because they cause a lot of other problems. If you can’t figure out what’s wrong with your machine, try adjusting the tension. I’m not an expert and don’t know a lot about sewing machines but I hope this blog helps with some basic problems and gives you some ideas for more complicated issues.

This is a great blog post on troubleshooting tension issues. Some of the issues in this post are more advanced than my own so I thought I would try to cover some of the more basic problems. If you find that your machine isn’t sewing straight or there are other problems with stitch consistency, check to make sure your needle plate is level and that you aren’t pinching the fabric under the presser foot. If you’re using a walking foot, check your needle plate for debris and make sure it’s installed correctly.

Bobbin tension

If you are having trouble with your stitching, check the tension on your bobbin to see if it is too tight or too loose.

You should be able to adjust the tension on your sewing machine without having to lift the presser foot or increase the bobbin tension. If you need to reset or fine tune the tension of your machine for some other reason, you can do it easily by turning off your sewing machine and lowering its pressure. You also need to lower your pressure when washing and drying your fabrics, especially if you want a more gentle clean.

Sometimes the tension on a sewing machine becomes slack over time so you can just get a better measurement by using a sewing tape measure to check the bobbin tensions. You need to be careful not to make any adjustments that will cause you to have uneven stitches and puckers in your finished seams. 

For example, if you change your bobbin tension and the result is that you have uneven stitches where the bottom thread is tighter than the top thread, check your top tension (the one that controls how hard or loose you press down on the machine). The tension on both sides of the fabric should be equal to maintain even stitching. If they aren’t equal then you will need to make a minor adjustment.

The tension on the underside of the fabric is just as important as the top tension, maybe more important. You want a consistent stitch across both layers so keep them equal.

Top tensions control how hard or loose you press down on the sewing machine while sewing and bottom tensions determine how tight or loose your stitches are after they are sewn. Usually, top tensions are tighter than bottom tensions but it’s not always the case. 

Your machine should have instructions for adjusting these settings and usually, there is a diagram that demonstrates what you should do to adjust. These settings should be: You will want to reset your machine’s tension after sewing different weight fabrics or after changing your thread. It doesn’t take long to make the adjustments but it helps to have a clear understanding of how they work so you can make them properly.

Don’t become frustrated with bad stitching or fabric that puckers. Just check your tension and your problems will go away.

The tension on your backstop screw is too tight or loose

The tension on your backstop screw affects the amount of space that’s open between the feed dogs and the fabric to stitch through. If this spacing is too small, you may need to adjust the tension located behind your presser foot, below your sewing machine’s tension discs. If the tension is too loose, the fabric won’t be able to feed through, even if there isn’t a problem with your feed dogs.

The backstop screw can also contribute to tension issues. If the backstop screw isn’t tight enough, it will loosen the space between your feed dogs and the presser foot but if it’s too tight, 

you may experience problems with stitch consistency or poor tension on your sewing machine.

The backstop screw is usually made of metal, has threading, and will stick out of the side of your machine. It should be located on the back left or right of your machine depending on whether you’re right or left-handed. 

If you’re using a walking foot, double-check to make sure the backstop isn’t interfering with the walking foot. When adjusting tension, check your other tension settings first before making any adjustments.

Sewing Machine Tension Issues

If you are facing any kind of tension problem in your sewing machine, it might cause these issues.

  1. Fabric stretching
  2. Poor stitch quality 
  3. Uneven stitches or skipped stitches
  4. Fabric puckers/stretching
  5. Difficulty with zipper construction

Fabric stretching

The most common issue is fabric stretching that you can face due to tension problems. If you are sewing with a heavier-weight fabric (such as denim, canvas, flannel, or denim) then it is easy to force the fabric to stretch. It is difficult to keep the tension level correct when sewing with heavy-weight fabrics and sometimes you may need to adjust your tension setting.

If you never set the tension correctly, it will be difficult to keep your stitches consistent and avoid puckering. It is important to make sure your tension is correct for the thickness of the fabric you are using.

The heavy-weight fabrics often cause a problem with the thread breaking and it is usually because the tension is set too high and too much force from the needle breaks the thread. If your sewing machine tension is set too loose, then you will have trouble with thread breakage and skipped stitches.

Poor stitch quality

If the tension is too tight or too loose, then you may have problems with:

  1. Thread breakage due to improper tension.
  2. Puckered fabric due to bad stitch quality.
  3. Loose stitches are often the result of a loose top thread tension that needs adjustment.
  4. Poor sewing results- low-quality products with uneven seams and puckered fabrics.

Many sewing machines have a function that you can use to adjust the pressure of your fabric so it will attach and feed smoothly. If you don’t use this function to adjust your stitches correctly, your stitches might be uneven or of poor quality.

Uneven Stitches or Skipped Stitches

If you have uneven tension or skipped stitches, then it will affect the entire fabric and make it difficult to sew.

The simplest way to check if your tension is right is to check the bottom of your fabric. If you see loops and loose threads on the bottom of the fabric, then you need to lower your tension. Too high tensions will cause too much friction on the top fabrics causing problems with alignment and skipped stitches or broken threads.

If you have a heavy-duty thread and you have to adjust the bobbin tension, then you may see skipped stitches or the thread may already break.

This can be caused by too much movement of the needle wheel and too tight of a top tension that causes a lot of pressure on the fabric.

Uneven Stitches

The uneven stitching is a result of misalignment and different thicknesses in the fabrics. It can cause threads to break and the stitches to be uneven. If you have a heavy-duty thread, then you may see the same effect as seen above.

I would suggest adjusting your bobbin tension for a more appropriate setting for the thickness of the fabric you are using. If you still see an uneven stitch, then there is probably a problem with your tension.

Try adjusting it again and make sure you are using the appropriate thread for your fabric.

Thread Looping on the Top

Typically, looping on the top can be caused by an improper bobbin tension or too much pressure in the top tension. It can also cause broken threads and skipped stitches. Check your tension, adjust them if needed and make sure that your thread is not old or damaged.

Fabric puckers/stretching

You need to adjust the top tension or increase the bobbin tension to prevent fabric stretching.

  • If you don’t do this, then you will get poor-quality stitching and torn threads.
  • If there is too much force in the top tension, then it will cause everything to move down and create puckers in your fabric.
  • It is important to balance both tensions because the top thread and bobbin thread are equally important for sewing.
  • If you don’t adjust these settings properly, you can cause the bobbin to break or the thread to break.

Difficulty with zipper construction

The most common reason for the difficulty in zipper construction or troubleshooting is because the tension of your machine is not set correctly for your fabric.

If you have a fancy zipper, then you will have to adjust the top tension so that it works properly.

You can’t just sew it and expect it to work properly. You should adjust both the top and bobbin tensions for proper results.

The ruler and seam guide is designed to be used with the correct pattern pieces and help guide you in making your measurements.

  • If the ruler and seam guide is not aligned correctly, then it can cause problems when sewing your garment.
  • If you have a precision sewing machine, then you can adjust the top tension so that it is consistent with the seam guide.
  • If you wish to adjust the bobbin tension as well, then you may need to check your bobbin case for integrity.

You can use a square ruler or a pin and bend it to line up with the seam guide on your machine.

Random loops

If you are getting a lot of bulk under the thread, try to change your thread tension to a lighter setting than the tension that is recommended for your fabric. Normally you will want to use a heavier top and bottom thread when sewing with knits but sometimes the extra weight of the thread pulls down on your fabric and creates loops around the stitches.

I sewed this shirt using several types of thread. Some were single strands while others were multi-ply and each had different tensions.

How to Adjust the Tension on A Sewing Machine?

If you are getting a lot of bulk under the thread, try to change your thread tension to a lighter setting than the tension that is recommended for your fabric. Normally you will want to use a heavier top and bottom thread when sewing with knits but sometimes the extra weight of the thread pulls down on your fabric and creates loops around the stitches.

If your tension is too loose, then the top thread will not pull enough to create a good stitch. If it is tight, then it will cause the bobbin thread to break or cause skipped stitches.

If you feel like your stitching isn’t quite right, then it could be because you have set the needle incorrectly. It can also get dull over time and will cause skipped stitches if you are sewing through a thick material.

If your stitch is inconsistent, then it could be because of an uneven tension on your machine. If the bobbin thread is causing skipped stitches, then loosen the tension on the bobbin thread and try again.

Sometimes the needle can get dull over time. If you are sewing a heavy material such as canvas, denim, or thick wool, then this could be the problem. You can also try changing to a ball point needle if the fabric is extra thick or dense.

Turn your hand wheel until the thread is at its highest tension and check your stitches. If they are still too loose, then try turning it back one more notch.

If you are getting loose stitches, then it could be because the bobbin casing is not tight. If the tension on the top thread and bobbin thread is too loose, then loosen it a notch.

If your bobbin thread is breaking or skipping stitches when sewing, then it could be because of an uneven bottom tension.

You can tighten or loosen both the top and bobbin tension to a tighter setting but you cannot change one more than the other. Once you have the settings adjusted properly, then you will know what works best for your machine.

Automatic Tension in a Sewing Machine

Some sewing machines have an automatic tension setting. If the bobbin is too tight, then it will cause thread breakage.

Look at your machine and see if you have this option. Oftentimes, the tension is shown on a dial or knob. You can compare your settings to the thread’s tag that comes with it.

To find the automatic tension setting, press the needle down and then move it up and down in several different directions. The stitches should be even and there shouldn’t be any gathering at all. If you have uneven stitches, then the tension should be set to a lighter setting.

Most of the time you will have to adjust the top and bobbin tension for proper results when sewing a heavy-weight fabric such as denim or canvas and for thick fabric like wool or stretch cotton fabric.

FAQ about sewing machine tension problems

Why is my sewing machine not holding tension?

If you have an automatic needle threader and it doesn’t seem to work correctly, then you may need to adjust the pressure. You can do this by going into the menu on your sewing machine. Some models have a tension button that can be adjusted for fine-tuning or for thicker fabrics.

What should sewing machine tension be set at?

If you are sewing a large piece of fabric such as a quilt, then you can adjust the pressure twice.

Trim to the right size Use a paper template to line up your pattern on the fabric and make sure that they are as even as possible. There should be no wrinkles in the fabric. Trim off excess material on all sides by using the pattern piece taped to the edge of your table.

How do I clean my sewing machine tension discs?

Using a window cleaner or hand soap can work. Be cautious and never use ammonia or other cleaners that contain bleach.

If you need to adjust your sewing machine tension, then check the thread guide to see if there are any marks on your disc. If the marks are red or pink, then the disc has gotten dirty and needs to be cleaned. Move the needle up and down in several sets of sewing instructions until you find one that is working for you.

Why is my sewing machine making loops underneath?

Loop formation is often caused by the needle jumping up or down. This can be from a heavy material that causes the needle to jump in and out, or from a thicker thread. Try adjusting your tension again and check to see if it helps.

You should adjust your tension so it is between the top thread’s tension setting and the bobbin thread’s tension setting.

How often should you clean and lubricate the sewing machine?

Sewing machines need to be cleaned and lubricated after every 50 hours of sewing. If you are sewing a lot of heavy fabric such as canvas, denim, or thick wool, then you may need to clean the machine twice in one day.

You can use a dry cleaning spray or a lint roller. If you do not have one handy, then try using compressed air to remove any loose needles and lint that can build up under the thread guide or bobbin case. How do you replace the tension spring on a sewing machine?

What happens when you don’t oil your sewing machine?

It can damage the machine and make it run rough. If you let a sewing machine sit around for a long period without lubricating it, then you will notice that the metal parts do not slide properly. Your needle may get stuck and your thread may get caught up on the metal parts.

How do I adjust the tension on my bobbin thread?

You can adjust the tension by moving the bobbin thread screw up or down. If you notice that your thread is snagging when you start sewing, then it could be because your bobbin tension is not tight enough. If your thread ends are fraying or not sewing properly, then you may need to adjust the top tension setting.

Why is my thread loose on the top?

If the top thread is not tight enough, then it can cause the bobbin thread to flop over. This can make your stitches uneven and the fabric comes out in a bunch of threads.

Sometimes when a part breaks on your sewing machine, you may notice that the bobbin thread is loose or fraying. If this happens, then you may have to replace the entire bobbin. It would be in your best interest to change it if any parts break on your machine.

Final Thoughts

The sewing machine tension is what keeps your machine in place and how it can slide easily. If a machine does not have the proper pressure on the top thread and bobbin thread, you will notice that the stitches are uneven. The thread may break and you may also have loops underneath your stitches.

Adjusting the tension on your sewing machine is necessary for proper sewing. You should check your machine every time you use it and make sure that the threads are in good condition. This will ensure that you get a smooth finish on your project.


  1. Fixya – Sewing Machine Thread Tension problems
  2. Fixya – How do I fix the lower bobbin tension on my Bernette 66 sewing machine?
  3. Wikihow – How to Adjust the Tension on a Sewing Machine
  4. Reddit – Can’t get tension right (or something)



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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