Upper Thread Tightened Up; Tangled Thread On Wrong Side Of Fabric; Incorrect Thread Tension - Brother 888-E30 Operation Manual

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.
a Lower side of fabric
b Lower thread visible from upper side of fabric
c Upper thread
d Upper side of fabric
e Lower thread
■ Cause
Incorrect lower threading
If the lower thread is incorrectly threaded, instead of
the appropriate tension being applied to the lower
thread, it is pulled through the fabric when the
upper thread is pulled up. For this reason, the thread
is visible from the upper side of the fabric.
■ Remedy/check details
Correctly install the lower thread.
• Refer to "Lower threading" (page 13-15).
Tangled thread on wrong side of
fabric
■ Symptom
• The thread becomes tangled on the lower side
of the fabric.
• After starting sewing, a rattling noise is made
and sewing cannot continue.
• Looking under the fabric, there is tangled
thread in the bobbin case.
■ Cause
Incorrect upper threading
If the upper thread is incorrectly threaded, the upper
thread passed through the fabric cannot be firmly
pulled up and the upper thread becomes tangled in
the bobbin case, causing a rattling noise.
■ Remedy/check details
Remove the tangled thread, and then correct the
upper threading.
a Remove the tangled thread. If it cannot be
removed, cut the thread with scissors.
• For details, refer to "Cleaning the race" on
page 57.
b Remove the upper thread from the machine.
c Correct the upper threading by following the
instructions in "Upper threading" (page 15-17).
• If the bobbin was removed from the bobbin
case, refer to "Lower threading" (page 13) and
"Remedy/check details" in the section "Upper
thread tightened up" (page 59) to correctly
install the bobbin.

Incorrect thread tension

■ Symptoms
Symptom 1: The lower thread is visible from the
upper side of the fabric.
Symptom 2: The upper thread appears as a straight
line on the upper side of the fabric.
Symptom 3: The upper thread is visible from the
lower side of the fabric.
Symptom 4: The lower thread appears as a straight
line on the lower side of the fabric.
Symptom 5: The stitching on the lower side of the
fabric is loose or has slack.
 Symptom 1  Symptom 3
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