Uneven Seams 2); Uneven Seams 3); Uneven Seams 4) - Brother LH4-B800E Service Manual

5. Troubleshooting guide
5-4. Uneven seams 2)......Around rear tack or front tack
Cause
Thread Tension release timing
release
Threading Refer to "5-1. Needle thread breakage"
Zigzag Zigzag tension disc
tension opening
5-5. Uneven seams 3)......Loose thread end at end backtack (1)
Cause
Backtack Check the backtack
shape shape
Cause
Backtack Refer to "5-5. Uneven seams 3)......Loose thread end at end backtack (1)"
shape
Uneven Presser foot pressure
material
feeding
Upper clamping foot
Upper thread scissors
opening timing
Lower thread clamp
opening timing
5-6. Uneven seams 4)......Sticking in needle plate
* Front and rear tack sections of material gets stuck in needle hole
Cause
Start Start backtack
backtack
Rear tack Rear tack vector shape
Needle plate Needle plate
5 - 6
Check
Use the parameter
switches to change the
on and off timing.
Adjust the opening of
the tension discs.
Check
Set the value for
parameter No. 68 to
1.0.
Thread sticking out at end backtack (2)
Check
Increase presser foot
pressure
When using knit
material, replace with
the -3 thread clamp
and needle plate.
Adjust to an
appropriate opening
timing.
Adjust to an
appropriate opening
timing.
Check
Reduce the number of
front tack stitches
(parameter No. 40).
Change the rear tack
vector shape to
rectangle (parameter
No. 37).
When using knit
material, replace with
the -3 needle plate.
Replace with a needle
plate with a 1.2 needle
hole.
Solution
63
Solution
When the value for parameter No.
68 is set to 1.0, the end backtack
shape changes.
Solution
Using the thin -5 needle plate and
flat work clamp can be effective.
Solution
If the material is soft, setting to 0
stitches may help.
When the rear tack vector shape is
set to rectangle, it can help to set
the tack width to a narrower width.
Using the thin -5 needle plate and
flat work clamp can be effective.
LH4-B800E
64 65 66
1.0
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(Instruction)
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(Instruction)
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