A sewing machine is a mechanical device with a small number of moving parts and one job: to repeat a single action thousands of times. It does not need much, but it does need the little it needs, regularly.
The five-minute routine
After every bobbin, which for most people is every project or two, do these five things. Together they take about five minutes and prevent the majority of faults.
- Remove the bobbin case and brush the lint out of the bobbin area.
- Take the needle plate off if it is removable and clear the feed dogs.
- Put in a fresh needle, whether or not the old one looks worn.
- Check the tension discs for fluff and blow them out with a can of air.
- Run a test seam on a scrap before you start the project.
Unplug before you clean
Unplug the machine before you remove the needle plate, change a needle, or reach into the bobbin area. A machine that is switched off but plugged in can still start if the pedal is pressed.
The faults and their real causes
| Fault | Common cause | Fix |
|---|---|---|
| Skipped stitches | Blunt or bent needle, wrong point type | Replace the needle, match the point to the fabric |
| Thread breaks repeatedly | Tension too tight, or a burr on the hook | Reduce tension, inspect the hook for damage |
| Loops underneath | Thread missed the take-up lever | Re-thread from the spool, foot raised |
| Machine sounds rough | Lint in the mechanism, or no oil | Clean and oil to the manual |
| Feed not moving the fabric | Feed dogs lowered, or packed with lint | Raise the feed dogs, clear the lint |
| Needle hits the plate | Needle bent, or the wrong needle plate | Replace the needle, check the plate |
Oiling, and how much
Modern domestic machines are largely sealed and self-lubricating, so follow the manual rather than oiling everything that moves. Older and semi-industrial machines need a drop of machine oil at the marked points every few hours of use. The rule in both cases is the same: a drop, not a puddle, and never oil the tension discs.
Needles are the cheapest fix
A needle costs almost nothing and causes more faults than any other part. A blunt needle punches rather than pierces, which damages the cloth and causes skipped stitches that look exactly like a tension fault. Replace the needle every six to eight hours of sewing, and immediately after sewing through anything heavy.
Keep a maintenance log
Note the date and the hours each time you clean and oil. A machine that gets a clean every ten hours of sewing rarely develops the faults that stop a project halfway through.
When to stop and get it serviced
Some faults are not user-serviceable. If the timing is out, if the machine skips consistently no matter what needle you fit, if there is a grinding noise from the mechanism, or if the hook has visible damage, it needs a technician. Turning the tension dial or changing the needle will not fix a mechanical fault, and continuing to run it can make the damage worse.
A service every year or two, depending on use, costs less than the fabric one ruined project wastes.
