Download  Print this page

Troubleshooting Guide; Needle Thread Breakage - Brother LH4-B800E Service Manual

Electronic lockstitch button holer.
Hide thumbs

Advertisement

5. TROUBLESHOOTING GUIDE

5-1. Needle thread breakage

Cause
Needle
Needle facing
Needle installation
height
Bent needle
Blunt needle tip or burr
Needle and thread
Threading
Needle thread
threading
Bobbin thread
threading
Thread path
Flaw or abrasion on
the thread path
Rotary hook point
Rotary hook edge
Flaw on the rotary
hook holder
Thread
Sub thread tension
tension
(Zigzag chain stitch)
Main thread tension
Check
Reattach needle
properly
Install the needle at the
correct height.
Replace needle
Replace needle
Replace needle that fits
the thread
Rethread properly
Rethread properly
Polish with buff
Replace the part
Polish with buff
Replace the part
Polish with buff
Replace the part
Adjust the needle
thread tension
Adjust the needle
thread tension
Solution
As viewed from the direction of the
face plate, attach needle so that the
notched part of needle faces
frontward
Insert the end of the needle shank
so that it touches the top edge of
the needle hole of the needle bar.
Cutton, spun yarn Man-made fiber filament
yarn
Especially, pay attention to finishing
around needle plate hole
1 - 2.2N tension for spun yarn #50 -
#60
Bobbin thread tension
Whip stitch 0.15 - 0.25N
Purl stitch 0.05 - 0.15N
(Holding the thread steady, the
bobbin case should gently descend
under the force of its own weight)
Adjust it while checking stitches
LH4-B800E
5. Troubleshooting guide
Purl stitch (Seal stitch)
Whip stitch (Plain stitch)
Needle plate hole
Check flaw here
Adjust the rotary hook
overlap amount.
page
-
(Instruction)
-
(Instruction)
-
-
-
-
(Instruction)
-
(Instruction)
-
-
4-8
-
(Instruction)
-
(Instruction)
5 - 1

Advertisement

Table of Contents

   Also See for Brother LH4-B800E

   Related Manuals for Brother LH4-B800E

Comments to this Manuals

Symbols: 0
Latest comments: