Problem
Cause
Correction
Reference
Loose
stitches
1. The machine is not correctly
threaded.
1. Check the threading and
rethread.
11
2. The bobbin case is not
threaded correctly.
2. Thread the bobbin case as
illustrated.
8
3. Needle/fabric/thread
combination is wrong.
3. The needle size must suit the
fabric and thread.
15
4. The thread tension is wrong.
4. Correct the thread tension.
18
Seam gather
or pucker
1. The needle is too thick for the
fabric.
1. Select a correct needle size.
15
2. The stitch length is wrong.
2. Adjust the stitch length.
22
3. The thread tension is too tight.
3. Loosen the thread tension.
18
Seam
puckering
1. The needle thread tension is
too tight.
1. Loosen the thread tension.
18
2. The needle thread is not
threaded correctly.
2. Rethread the machine.
11
3. The needle is too heavy for the
fabric being sewn.
3. Choose a needle to suit the
thread and fabric.
15
4. The stitch length is too long for
the fabric.
4. Adjust the stitch length shorter.
22
5. Sewing on thin fabric.
5. Sew with a stabilizer material
under the fabric.
26
Patterns are
distorted
1. The presser foot is not suited
for the pattern.
1. Select the correct foot.
-
2. The needle thread tension is
too tight.
2. Loosen the thread tension.
18
Thread has
jammed
1. Thread is caught in the hook.
Remove the upper thread and
bobbin case, turn the handwheel
backwards and forwards and
remove the thread remnants.
48
2. The feed dogs are packed with
lint.
The
machine is
noisy
1. Fluff or oil have collected on
the hook or needle bar.
1. Clean the hook and feed dog.
48
2. The needle is damaged.
2. Insert a new needle.
14
3. Thread is caught in the hook.
Remove the upper thread and
bobbin case, turn the handwheel
backwards and forwards and
remove the thread remands.
48
4. The feed dogs are packed with
lint.
Uneven
stitches,
uneven feed
1. Poor quality thread.
1. Select a better quality thread.
15
2. The bobbin case is threaded
uncorrect.
2. Remove the bobbin case and
the thread and reinsert them
correctly.
8
3. Fabric has been pulled on.
3. Do not pull on the fabric while
sewing, let it be taken up by
the machine.
-
50
Summary of Contents for Q421A
Page 1: ...Instruction Manual Q421A...
Page 2: ......
Page 7: ...Machine Introduction...
Page 11: ...Machine Setup...
Page 25: ...Sewing Basics...
Page 34: ...Utility Stitches...
Page 53: ...Maintenance and Trouble shooting...
Page 58: ......
Page 59: ......
