Troubleshooting; Frequent Troubleshooting Topics; Upper Thread Tightened Up - Brother NQ3600D Operation Manual

Troubleshooting

If the machine stops operating correctly, check the
following possible problems before requesting service.
You can solve most problems by yourself. If you need
additional help, the Brother Solutions Center offers the
latest FAQs and troubleshooting tips. Visit us at " http://
support.brother.com/ ".
If the problem persists, contact your Brother dealer or the
nearest Brother authorized service center.

Frequent troubleshooting topics

Detailed causes and remedies for common troubleshooting
topics are described below. Be sure to refer to this before
contacting us.

Upper thread tightened up

Tangled thread on wrong side of fabric
Incorrect thread tension
Fabric is caught in the machine and cannot
be removed
When the thread becomes tangled under
the bobbin winder seat
Upper thread tightened up
■ Symptom
• The upper thread appears as a single continuous line.
• The lower thread is visible from the upper side of the
fabric. (Refer to the illustration below.)
• The upper thread has tightened up, and comes out
when pulled.
• The upper thread has tightened up, and wrinkles
appear in the fabric.
• The upper thread tension is tight, and the results do
not change even after the thread tension is adjusted.
1 Wrong side of fabric
2 Bobbin thread visible from right side of fabric
3 Upper thread
4 Right side of fabric
5 Bobbin thread
■ Cause
Incorrect bobbin threading
If the bobbin thread is incorrectly threaded, instead of the
appropriate tension being applied to the bobbin thread, it
is pulled through the fabric when the upper thread is
pulled up. For this reason, the thread is visible from the
right side of the fabric.
■ Remedy/check details
Correctly install the bobbin thread.
a Press
b Remove the bobbin from the bobbin case.
c Place the bobbin in the bobbin case so that the thread
page A-5
unwinds in the correct direction.
page A-6
• Hold the bobbin with your right hand with the thread
page A-7
page A-8
page A-11
If the bobbin is inserted with the thread unwinding in
the wrong direction, sewing will be done with an
incorrect thread tension.
d While holding the bobbin in place with your finger,
pass the thread through the slit in the needle plate
cover.
• Hold down the bobbin with your right hand, and
1 Tab
2 Hold down the bobbin with your right hand.
and raise the presser foot lever.
unwinding to the left, and hold the end of the thread
with your left hand.
Then, with your right hand, place the bobbin in the
bobbin case.
then pull the end of the thread around the tab with
your left hand.
Troubleshooting
A
Appendix A-5