The most common problem with sewing machines is the correct tension. Thread tension refers to the maximum amount of thread that can pass through a machine to create a stitch. The looser the stitch will be, the more thread there is. The tighter the stitch, the less thread is needed.
The machine’s thread path has a dial that controls the top thread tension. Ensure the thread is properly aligned between the tension discs when threading your machine. The machine will not be able to sew if it does not work properly. The tension discs on your top thread are not tightened when the presser foot is raised.
This is why you will get lots of loops if you sew with your presser foot. It does help to get thread between the discs if you keep your foot up while you thread the sewing machine. Thread tension is an important topic that is often misunderstood. We cover it in the Beginner’s Sewing classes.
How Can You Tell if Your Tension Is the Problem?
If you still have trouble following the Threads Magazine checklist, we suggest you adjust your tension slowly with a scrap of fabric. Do not touch the tension knobs if your stitches are perfect and your machine is sewn well. This will not affect your actual project.
Please Read the Following Before Touching Your Tension Dial
- The hook has had a drop of oil added (if applicable).
- For the correct technique and fabric, attach the appropriate presser foot.
- Incorrectly threaded machine. Did you use all the thread guides? Do you have the presser foot up? This would prevent the thread from sliding between the tension discs. Are threads unwinding easily from the spool or catching on the blade of the spool? Is the bobbin being used as a spool? This can cause the thread to clog. Is your bobbin correctly inserted?
- Dirty machine: Lint, thread ends, and other debris can build up around the bobbin and bobbin or under the throat plate. Use a lightweight, lint-free cloth to “float” between tension discs. This will increase resistance and reduce thread flow. Also, check the bobbin area and thread ends.
- Broken machine parts: Damaged needles and bobbins can cause problems. The smallest damage can cause tension distortions. You can avoid damage to the bobbin tension spring by cutting the thread near the case before you remove the bobbin.
- Before removing the thread from the upper tension, lift the presser foot. Even if the bobbin looks good, it is best to throw it away.
- Threads, needles, and fabrics: Many thread types and sizes can affect basic tension settings. Unbalanced stitches can be caused by a needle that is too small or large for the thread. The hole size affects how much tension the top will apply to your stitch. You may experience puckers when working with lightweight fabrics.
- Try switching to a straight-stitch needle plate and foot. Shorten the stitch length by 1.75mm (15 sts/in) before reaching the tension dials.
How to Adjust the Tension?
There are two types: a basic adjustment that you use for everyday sewing (your repair expert will do this, but you can also do it yourself) and a temporary adjustment when you change thread sizes or fabrics.
Choose contrasting colors in the size, brand, and fiber you use the most for a simple adjustment. To reduce the stretching of the thread, use one color to fill your bobbin.
Thread the machine with a needle the same size as your most used one. Use all thread guides on the sewing machine head to thread it. Skip threading the eye on your bobbin-case finger if that feature is available.
The stitch length should be set at 2 mm (12 stitches/inch) or the length you will use the most often. The upper-tension regulator should be set at the middle of the range. Most machines have this setting of 4 or 5. Next, stitch a test seam using two layers of lightweight fabric muslin.
Finally, examine the stitches. To see the stitches clearly, you can use a magnifier if necessary. Adjust the tension if it isn’t right. Check the stitch balance by making another test seam.
After your stitching has been balanced, create a tension log in the sewing machine manual. Include the brand, type, and size of the threads, along with the number on your upper-tension regulator. Draw a picture of the bobbin screw position, such as the one below, in case you need to change the settings.
Note the bobbin screw’s position to record tension. This includes reference to the bobbin case’s threaded opening and open side.
Select the appropriate threads for your needle and bobbin to adjust the tension temporarily. Then fill the bobbin with the required threads and thread the machine. Do a test seam with the fabric you intend to sew. Next, check the stitches and see if the tension adjustment works.
You should first thread your machine when switching from your regular sewing thread to another. Then, test your setup to figure out if you can make a temporary adjustment to the tension dial. If this fails, you can try a tension-dial-only, temporary adjustment.
The tensions will remain balanced even if you use lighter threads for the needle and bobbin. This is usually what you need to prevent lightweight fabrics from puckering.
No adjustment may be required. You will need to adjust the tensions to accommodate heavier fabrics if you have a heavier top or bottom thread.
How Can You Increase or Decrease Your Tension?
Now that you can tell which thread is tight or loose, how can you adjust it?
How to Adjust Top Tension?
You will first need to locate your tension-regulating dial. (See illustration of the sewing machine above). You will find it in different places on each machine. If you are unsure which knob it is, consult your manual. It will not affect the type or length of your stitches if you don’t have a manual.
If Your Top Tension Is to Loosen
In case your top tension is extremely loose, turn the knob until they are increasing. Start with 1/2 to 1 number lower. Next, test it on a scrap fabric with a different thread on top and bottom. Keep going until the fabric is even on both sides. If this is not possible, keep the bobbin tension adjusted until it is close to balanced.
If Your Top Tension Is Very Tight
In such a case, turn the knob until it decreases. Start with 1/2 to 1 number less, then try a lighter piece of scrap fabric and a different thread color on top and bottom. Keep going until the fabric is even on both sides. If this is not possible, keep the bobbin tension adjusted until it is close to balanced.
How Can I Adjust Your Bobbin Tension (Your Lower Tension)?
If possible, adjust your top tension first. If you’re using a lighter or heavier thread, your bobbin tension should be adjusted. A heavier fabric will require more tension. To adjust the dial, turn it to a higher number. A lighter fabric will need less tension. Mainely Sewing Machines making too many adjustments to the bobbin can cause it to lose its grip.
Each machine has either a bottom-loading bobbin case or a top-loading drop-in bobbin. The sewing machine shown above has a bottom loading case.
These are some things you should remember before adjusting bobbin tension.
- Is your bobbin winded correctly? It would be too tight or too loose.
- Are you sure that your machine has the right bobbin?
- Is your bobbin bag on the ground? It could be damaged, which can affect the tension.
- Adjusting your top tension will solve 90% of tension problems.
- You can test the tension using a seam using different colors for the top and bobbin threads. The thread must contrast with your fabric to make it easier to see your changes and make them more precise. Make sure you change to the correct color thread before you start sewing.
- A tension log is a great idea for your sewing machine. Keep a notebook list of the tensions that work with specific fabrics, threads, or needles. Keep track of the type, size, and brand. This will simplify the adjustment process in the future.
- When sewing a seam, keep the thread tails away from the needle. Otherwise, “bird nesting” could occur. This is another frustrating problem for novice machine operators.