1. Check whether the small thread clamp of the automatic sewing machine is under too much pressure. It mainly controls the length of the thread end. If the pressure of the small thread clamp is too high, the thread end is too short, and the thread end will come out of the needle hole during sewing.
2. Pay attention to see if the large thread tensioner bounces off. If it doesn't pop open, push the large thread tensioner in the sewing machine inward a bit.
3. Check the position of the thread trimming cam of the sewing machine to see if the installation position is correct.
4. Check whether the hand wheel of the sewing machine is installed correctly.
5. Check whether the thread reel and the thread passer on the sewing machine are vertical. If the angle difference between the thread reel and the thread passer is too large, the upper thread resistance will be too large, and the thread end will be too short when the thread is trimmed.
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