Cause: The upper thread is used up; the presser foot is not lowered; the bobbin thread shaft is not in the correct position.
Solution: Replace the empty spool and re-identify the needle; lower the presser foot; press the bobbin spool to the end and return to the left; lower the buttonhole lever.
During the use of the sewing machine, many faults can be solved simply on the working surface, and there is no need to ask a mechanic to do a lot of work, such as flipping the switch or even replacing the needle only once. If it works, it can avoid a long time. Site work stoppage and dismantling of the machine caused a mess on the work surface. The following lists some minor faults that often occur during sewing and how to remove them:
Sudden stop during sewing; the power indicator light is on, but the handwheel is stagnant.
1. Possible cause (hereinafter referred to as "cause"): The sewing machine has been working at a low speed for a long time; overheating of the machine may cause the motor to automatically shut down.
Solution (hereinafter referred to as "solution"): Turn off the power and wait for 20 minutes, the safety device will restart, and the sewing machine is ready to start working.
2. Upper thread is broken
Reasons: improper threading method; thread knotted; thread tension is too large; the needle is bent, blunt or blistered; the needle size is incorrect; the needle is not properly placed; the needle and thread are not properly matched; the initial sewing speed is too fast; the thread is not picked up Wire device.
Solution: Restart the thread normally; eliminate knots in the thread; adjust the pressure of the thread clamp; replace the needle; replace the needle of the appropriate size; properly place the needle; change the thread or needle; start the sewing machine at a medium speed; check the threading procedure .
3. Jumper
Cause: The thread tension is too large; the needle is bent or blunt; the needle size is wrong; the needle and thread are not matched properly; the thread has not passed through the thread take-up lever; the pressure of the presser foot is not enough; the needle is not properly positioned.
Solution: adjust the thread tension; replace the needle; select the appropriate size needle; replace the needle or thread; check the threading steps; increase the pressure of the presser foot; re-load the needle.
