The short answer: balance the top tension
- A balanced stitch shows the top and bobbin threads meeting in the middle of the batting, so neither thread is visible on the wrong side of the quilt.[1][3]
- Eyelashes on the back mean the top tension is too loose. Eyelashes on the top mean it is too tight.[1][2]
- To tighten the top tension, select a higher number on a digital machine or turn the knob to the right on an analog one. To loosen it, go lower or turn left.[1][2]
- Lori Kennedy writes that almost no machine in good working order needs the bobbin case adjusted. The Quilt Skipper describes a case where the best balance fell between two top settings and the bobbin had to be adjusted, so the bobbin is worth checking only after the top tension has been tried.[3][5]
How to read the stitches on both sides of the quilt
Eyelashes are the most common problem, and they show on the back first, because you cannot see the back while you quilt. Little loops of top thread on the back mean the top tension is too loose and the bobbin thread is winning. A stitch can look fine on the front while the back is wrong, so turn the quilt over early and check again.[1][2]
Eyelashes on the top point the other way. The top thread is too tight and pulls the bobbin thread up to the surface. They often hide at the centre of swirls, so look there closely.[1][2]
Floaters are harder to spot. The twist of the two threads sits just above or just below the fabric instead of in the batting. String & Story says that if the top thread floats on the surface, the top tension should be loosened, and if the back thread floats, it should be tightened. HollyAnne Knight describes the back case the same way: a thread floating on the back of the quilt means the top tension is too loose, so tighten it a little. Make one small change at a time and judge the result on both sides of the quilt.[1][2]
Too tight looks different. The back stitches look strained and the top stitches look indistinct. Curves and sharp points show these problems first, so include them in your test.[6]
How to check and adjust tension before you quilt
- Start with the basics: put in a fresh needle oriented correctly for your machine, and brush lint from the bobbin race and around the feed dogs. Brush it out rather than blowing it in, and oil the machine as your dealer or manufacturer recommends.[1]
- Raise the presser foot before you thread or adjust the tension. The tension discs close when the foot is lowered, so thread cannot seat properly while it is down. Lower the foot fully before you sew.[2][4][5]
- Rethread the machine straight from the spool first, then sew a test. Dara Tomasson of Stitched Quilting Company suggests this as the first step, and says to check whether it made a difference before changing anything else.[7]
- Check the bobbin. Dara Tomasson advises making sure the bobbin is wound evenly and threaded with good pressure, and that the bobbin case is neither too tight nor too loose for the thread to pass at an even rate. Each machine and thread varies, so check your manual for the bobbin case.[7]
- Make a practice sandwich from scraps of the same batting, backing and fabric as the quilt, using the same thread, needle and presser foot. Include loops, zigzags, curves and points, since problems show up most there.[2][6]
- Sew for about 30 seconds, then look at both sides. Dara Tomasson recommends this check after each change.[7]
- Change only one thing at a time, and make the change small. Tomasson advises moving the top tension up a little and testing again, and The Quilt Skipper also recommends small, incremental movements.[5][7]
- Find the top tension dial or number in your machine manual before you start, since its location and scale differ between models.[2]
- Repeat the test every time you turn the machine off and on, change a bobbin, thread colour or needle, or start a new quilt. String & Story says this is the step most often skipped.[2][6]
Troubleshooting by symptom
| Symptom | Likely cause | What to try |
|---|---|---|
| Eyelashes on the back[1][2] | Top tension too loose, so the bobbin thread wins and top thread shows on the back | Raise the top tension one small step, quilt a few swirls on the practice sandwich, and check both sides. Find the top tension control in your machine manual. |
| Eyelashes on the top, often at the centre of swirls[1][2] | Top tension too tight, which pulls the bobbin thread to the top | Lower the top tension in small steps and check the centre of swirls. Confirm the control location in your machine manual. |
| Floaters: the thread twist sits on the surface instead of in the batting[1][2] | Floating on the top: top tension too tight. Floating on the back: top tension too loose (String & Story; HollyAnne Knight for the back) | Top floating: lower the top tension one small step. Back floating: raise it one small step. Test on the practice sandwich and find the top tension control in your machine manual. |
| Top thread keeps snapping[1][2][7] | Top tension too tight, a burr on the needle, needle plate or presser foot, poor thread quality, or incorrect threading | Ease the top tension a little and check the back for loops. Look for burrs and replace a worn needle. Rethread from the spool. Use your machine manual for threading and the tension control. |
| Tension changes along a curve or point[5][7] | Sewing faster on curves than on straight lines, so the needle flexes and the bobbin cannot keep up | Keep the same speed on curves as on straight runs, and match needle size to thread. Check your machine manual for speed and needle guidance. |
| Tension dial makes no difference[5] | Lint between the tension discs, or a restricted thread path such as thread caught on the spool holder or an add-on light | Gently floss the discs by moving thread back and forth through them, then check the thread path. Use your machine manual to locate the discs and the threading route. |
| Loops or a bird's nest under the fabric when sewing starts[2][4] | Presser foot left up, so the tension discs did not engage | Lower the presser foot fully before sewing, and rethread with the foot up if needed. Your machine manual shows the threading route and foot position. |
Mistakes that cost the most unpicking time
Skipping the check after restarting. String & Story describes an hour of quilting that took four hours to unpick because the tension had changed. Check the back again after every restart.[6]
Adjusting with the presser foot down. Raise the foot to adjust, then lower it to sew.[1][2]
Testing on a different sandwich from the quilt. Tomasson notes that machine tension needs to match the project, so the practice sandwich should use the same materials.[6][7]
Changing several settings at once. Tomasson and HollyAnne Knight both advise changing only one variable, so you can tell which change made the difference.[1][7]
Sewing faster on curves. The Quilt Skipper links eyelashes on curves to speed, and says that matching the speed on curves to the straight sections often clears it up.[5]
Questions readers ask about tension
Should I adjust the bobbin tension too?
Most guidance starts with the top tension. Lori Kennedy writes that almost no machine in good working order needs the bobbin case adjusted, while The Quilt Skipper describes a case where the best balance fell between two top settings and the bobbin was adjusted. Check your machine manual before touching the bobbin case screw, and ask a repair shop if you are unsure.[3][5]
What if the tension is still wrong after I adjust it?
Check the needle, the bobbin area and the threading first, since a burr, a worn needle or lint can cause problems. Lori Kennedy notes that if the top and bobbin threads meet in the centre but both are too tight, the machine may need professional service. Dara Tomasson suggests a repair shop or videos for your model if the problem continues after these checks.[1][3][7]
Can I use different thread weights or types together?
The Quilt Skipper says yes, and that mixing weights or fibres such as polyester, cotton and silk makes tension harder to adjust. Use a mix only if the look is what you want.[5]
Which thread and needle should I start with?
Dara Tomasson of Stitched Quilting Company uses So Fine by Superior thread, a 50 weight, with a 90/14 needle, and recommends top stitch needles for the best results. Match needle size to thread weight, and check your machine manual for the needle your model takes.[7]
Is there a bobbin case made for free motion quilting?
Lori Kennedy says Janome sells a blue dot bobbin case with a lower tension for free motion quilting, and that swapping the case can change the tension without adjusting the screw on the supplied case. Check that it fits your model in your machine manual.[3]
What we could not confirm
- How often domestic machines need bobbin case adjustment: Lori Kennedy says almost never in good working order, while The Quilt Skipper describes a case where it was needed.
- The exact location, scale and range of the top tension control on your model, which only your machine manual shows.
- The sewing speed that suits your machine on curves and points, which varies by model and thread.
- Whether a computerised machine sets tension automatically and how much you can override it, which sources do not explain for specific models.
- Whether a blue dot bobbin case fits your machine model; check your manual or the maker before buying.
Sources
- Sewing Machine Tension for Free Motion Quilting with HollyAnne Knight – auribuzz — checked 2026-10-27
- How to Have Perfect Sewing Machine Tension for Free Motion Quilting — String & Story — checked 2026-10-27
- Proper Tension for Machine Quilting - Lori Kennedy Quilts — checked 2026-10-27
- How to Get Perfect Tension — Karen Bolan Designs — checked 2026-10-27
- More about balanced thread tension – The Quilt Skipper — checked 2026-10-27
- Tips Tuesday: How to Check Your Sewing Machine Tension Before Quilting — String & Story — checked 2026-10-27
- Sewing Machine Tension Troubleshooting for Quilting at Home - Diary of a Quilter - a quilt blog — checked 2026-10-27