Machine 3 Skips, Loops and Puckers on Fine Georgette
The school workshop has six power machines. A student is hemming a light polyester georgette dupatta on Machine 3. The machine skips two or three stitches in every 10 cm, loops and tangles form under the fabric, and the fine cloth puckers along the seam. The needle is a size 14 sharp that was used last week on denim; the top thread is a thick 40-count polyester while the bobbin holds a fine 60-count; the tension dial is set at 6 where the class normally uses 4; there is visible lint in the bobbin case and a small burr on the needle plate. The student has long loose hair, is leaning within 10 cm of the needle to watch the stitching, and yesterday the same machine threw a broken needle that flew past her face. The teacher has stepped out for ten minutes.
1. List, in the correct order, what should be checked and changed on Machine 3 before this hem is re-stitched, with the reason for each step.
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Order matters: stop the machine, then work outwards from the simplest fault.
- Switch off and unplug before touching the needle area - hands near a needle on a live machine cause the injury, not the stitching fault.
- Clear the lint from the bobbin case and feed dogs. Lint packs the bobbin case, stops the bobbin turning freely and produces exactly the tangles seen under the cloth.
- Fit a new needle, size 60–70 (9–11) sharp for fine polyester. The size 14 needle is the single biggest cause of skipping: it was also used on denim and is likely blunt or slightly bent, so it does not form a clean loop for the hook to catch, and it punches a hole bigger than the thread.
- Match the thread: fine polyester top and bobbin, same count. Thick 40s on top with 60s underneath cannot balance at any dial setting, and the surplus top thread is what loops underneath.
- Reset the tension to about 4, then adjust only on a scrap - high tension puckers georgette and stretches the seam.
- Deal with the burr on the needle plate; it snags filaments, causes skipped stitches and pulls threads. Replace the plate or report it; do not 'fix' it by increasing tension.
- Test on a double scrap over tissue paper, not on the dupatta, and check both sides of the seam.
2. Explain, in cause-and-effect terms, why this needle–thread–fabric combination both skips stitches and puckers.
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Skipping happens when the hook fails to catch the loop of top thread. Three faults here combine: a size 14 needle is too heavy for georgette, so it displaces the fine yarns instead of piercing cleanly and the loop forms unevenly; a needle used on denim is often slightly bent or blunt, so the loop is small or late; and a thick top thread needs a larger needle eye and a bigger loop than the hook is timed for. Lint in the bobbin case and a burr on the plate add friction, holding the loop back.
Looping underneath is a tension imbalance, not a bobbin fault by itself. Thick 40-count top thread with fine 60-count bobbin thread means the two threads pull against each other unequally, and the surplus top thread is pushed to the underside. Raising the dial to 6 makes it worse, not better, because it also pulls the fine georgette.
Puckering is the result of a heavy needle and high tension on a very light fabric: the seam is stretched as it is sewn and relaxes into ripples, and the needle holes are too large for the yarns to close. Matching needle, thread and tension is what solves all three symptoms together; changing only one of them usually moves the fault rather than removing it.
3. Give four safety rules the student must follow in the ten minutes the teacher is absent, and say why each one applies to this specific situation.
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- Tie the hair back and remove loose jewellery or dupatta ends before sitting down. Long loose hair near a needle and take-up lever is the classic workshop accident, and this student is already leaning close.
- Never lean into the line of the needle. Yesterday's broken needle flew past her face - that is the trajectory a needle takes when it breaks. Watch the seam from the side, with the presser foot and fabric between her and the needle.
- Switch off before threading, cleaning or changing the needle, and keep fingers at least 3 cm from the needle while the machine runs. She must clean lint and change this needle, so the machine has to be dead first.
- Report the burred needle plate and the broken needle to the teacher and do not use the machine until it is cleared. A damaged plate will keep throwing needles, and a machine with an unreported fault should be tagged out, not quietly used by the next student.
Add the everyday rules: sew at slow speed on fine fabric, never sew over pins, keep the machine covered when not in use, and do not leave a running machine unattended - the teacher's absence does not change any of these.