How do I thread a sewing machine and set the tension?

Most sewing machine problems are threading problems. The tension dial gets blamed for faults that are really caused by thread that never seated in the tension discs.

What you'll need

• The machine's manual, or the threading diagram printed on it
• Scrap fabric of the same type as your project
• A fresh needle

Step by step

1. Raise the presser foot before threading.This is the step people skip and it causes most tension complaints. The tension discs are clamped shut when the foot is down, so the thread lies past them instead of between them.
2. Follow the numbered path on the machine.Most machines have the route printed or moulded on. Every guide, including the small hook near the take-up lever, has to be used.
3. Pass the thread through the take-up lever.The moving arm near the top. A thread that misses it produces skipped stitches and loops immediately.
4. Wind and insert the bobbin correctly.Wind evenly at moderate speed, and drop it into the case so it turns in the direction the diagram shows. A bobbin in backwards gives constant tension trouble.
5. Bring the bobbin thread up.Hold the top thread, turn the handwheel towards you one full turn, and pull the top thread — a loop of bobbin thread comes up. Draw both threads back under the foot.
6. Fit a new needle the right way round.The flat side of the shank goes towards the back on most domestic machines. Push it fully up before tightening. A blunt or wrongly fitted needle causes skipped stitches and thumping.
7. Sew a test seam on the actual fabric.Two layers of the same material, in the same thread. Tension that is right for cotton is often wrong for jersey or denim.
8. Read the test stitch.Identical from both sides means balanced. Bobbin thread showing on top means the top tension is too tight; loops of top thread underneath mean the top thread is too loose or, far more often, not seated in the discs.
9. Adjust the top tension only, in small steps.Half a number at a time, re-testing each time. Leave the bobbin tension screw alone unless everything else is eliminated — it is easy to lose the setting entirely.
10. Rethread completely before adjusting anything.Take the thread out and start again with the foot up. This fixes the majority of tension problems on its own.

Tips

• Presser foot up when threading. Nothing else about tension matters until this is right.
• Test on the fabric you are actually sewing, not on a scrap of something else.
• Change the needle far more often than you think — every project or so, and always after hitting a pin.

Common mistakes

• Threading with the presser foot down — The tension discs are closed, so the thread slides past them instead of between them. The machine then sews with effectively no top tension whatever the dial says.
• Turning the bobbin tension screw first — Bobbin tension is factory set and rarely the cause. Once you have lost that setting it is fiddly to recover, and the actual fault is usually top threading.

If it doesn't work

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