Thread Tension Problems
Janome Sewing Machine
Severity: MinorWhat Does This Error Mean?
Thread tension problems on a Janome appear as loops of thread on the top or bottom of the fabric. If loops show on the bottom, upper tension is too loose (increase the tension number). If loops show on the top, upper tension is too tight (decrease the number). Almost all tension problems are caused by incorrect threading — re-thread first.
Affected Models
- Janome HD3000
- Janome MC9900
- Janome 6700P
- Janome Skyline S3 / S5
- Most Janome models
Common Causes
- Thread not seated in the tension discs (must thread with presser foot UP)
- Bobbin incorrectly threaded or inserted
- Wrong tension setting for the fabric weight
- Lint in the tension mechanism
- Damaged tension disc
How to Fix It
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Re-thread the upper thread with the presser foot raised.
The tension discs only open when the presser foot is up. If you thread with the foot down, the thread bypasses the tension entirely and produces inconsistent, loose stitches.
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Re-thread the bobbin following the arrows on the bobbin case.
Bobbin tension is also part of the stitch. Ensure the thread passes through the bobbin case slot and under the tension spring correctly.
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Test stitch on a scrap piece of the same fabric.
Sew a line of straight stitches and examine the fabric. If you see loops on top, increase the tension number by 1. If you see loops on the bottom, decrease by 1. The ideal stitch locks between the two layers of fabric.
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Clean the tension discs with a piece of thread.
Thread the machine normally, then slide a folded piece of thread back and forth through the tension area. This removes lint that can prevent the thread from seating correctly.
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Check that you are using the correct thread weight for the needle.
Heavy thread in a fine needle, or fine thread in a heavy needle, causes tension irregularities. Use thread and needle size that match the fabric weight.
When to Call a Professional
If the tension is uneven even after re-threading and cleaning, the tension spring or disc may be worn. Take the machine to a Janome dealer for inspection.
Frequently Asked Questions
What should my Janome tension setting be?
Most Janome machines default to tension setting 4, which works for medium-weight woven fabrics. For light fabrics like silk, try 3–3.5. For heavy fabrics like denim, try 4.5–5. Always test on a scrap first.
Why do I get loops under my fabric on my Janome?
Loops of thread on the underside almost always mean the upper thread tension is too loose, or the upper thread is not correctly seated in the tension discs. Re-thread from scratch with the presser foot raised and test again.