Brother HE-800A User Manual
Page 109

HE-800A
16. TROUBLESHOOTING
101
ውዒ-ውዐ. Unraveling of thread trimmed by upper thread trimmer assembly
Cause Check
Remedy
Page
Installation position of
upper thread trimmer
assembly
Adjust the installation position of upper thread
trimmer assembly by moving the setting plate
assembly.
Upper thread trimmer longitudinal position adjust-
ment
Upper thread trimmer cutting depth adjustment
Service
manual
Upper thread trimmer
assembly
Burr on tips of upper
thread trimmer M and
upper thread trimmer U.
Polish with buff or replace the part.
-
Tension release
timing
Opening amount of
zigzag tension discs and
bar tack tension discs
(particularly zigzag
tension discs)
Adjust the zigzag tension discs by moving the
tension stud bracket in and out.
Adjust the bar tack tension discs opening amount
to 0.5 - 1.0 mm by removing the top cover and
moving the tension release cam.
-
Work clamp
Work clamp lifting speed
Use memory switch No. 02 to retard the work clamp
lifting speed.
79
4009Q
4005Q
Check burr on upper
side here
Check burr here
4008Q
Tack tension
0.5 - 1 mm
Zigzag tension