21. | TROUBLE CHART |
PROBLEM | |
Breaking | lower |
thread |
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PROBABLE CAUSE
Thread not wound evenly | on | the | bobbin | ||
or not | drawn | up correctly |
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Lower | thread | tension too | tight |
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Lint stuck in | the bobbin case | and inside | |||
the tension spring |
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CORRECTION | ||
P10, | P15 | |
P12 | ||
Remove |
| lint |
and fluff | with a | |
cleaning | brush | |
Skipping
stitches
Needle | not fully | inserted |
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| |
Needle bent |
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| ||
Size or | type | of | needle and | thread | not |
suitable | for | the | material |
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P | 6 |
P | 6 |
P16 | |
Irregular
stitches
Incorrect | upper | threading |
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| ||
Too much | oil | on | the | hook |
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Incorrect | size | of | needle for the | material | ||
Upper thread | tension too | loose |
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P13 |
P45 |
P16 |
P20 |
Th material fed correctly
not
Incorrect | lower | tension |
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| |
Pattern selection dial not | set | correctly | |||
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Incorrect | feed | dog | height |
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P12 |
P17 |
P12 |
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| Lint stuck | on the feed dog |
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Noisy | machine | I | Check for | thread in | race, the |
| race | may | ||
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| slightest amount of | thread in |
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| cause noise or | binding, | use | material | ||||
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| like tooth | pick | or cotton | swab | to |
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| clean. |
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P44 |
P45 |
