Brother HE-800A - Manual (Page 101)

HE-800A
16. TROUBLESHOOTING
93
Cause Check Remedy Page
Needle bar height and
needle bar lift amount Adjust the needle and hook timing.
1. Adjust the needle bar height to “1” on the gauge.
2. Adjust the needle bar lift amount to “2” on the
gauge.
72, 73
Gap between needle and
rotary hook Adjust the gap between needle and rotary hook to
0.01 - 0.08 mm. (Adjust to as large as possible
without causing skipped stitches to occur.)
* Check that rotary hook point does not strike
needle in zigzag motion.
73
Rotary hook lubrication ࡮Too small quantity of lubrication oil will cause
thread breakage. Adjust the quantity of lubrication
oil.
࡮The lubrication holes between rotary hook and
rotary hook joint do not match up.
25
73
Rotary hook
Thread twisted around
rotary hook Remove any twisted thread from the inner and
rotary hook.
-
Upper thread amount Arm thread guide position Adjust the arm thread guide position 63
Bobbin case Damaged outside of
bobbin case and bent
bobbin holder spring, etc.
Polish with buff or replace the part.
* Use the HE-800A bobbin case.
-
ውዒ-ዎ. Skipped stitches
Cause Check Remedy Page
Needle facing As viewed from the direction of the face plate,
attach needle so that the notched part of needle
faces frontward.
57
Needle installation height Insert the end of the needle shank so that it touches
the top edge of the needle hole of the needle bar.
-
Bent needle Replace needle -
Blunt needle tip or burr Replace needle -
Needle
Thin needle Use a needle with a count that matches the thread
and material.
-
Thread take-up
spring Thread take-up spring
tension and stroke Loosen the thread take-up spring tension or shorten
the stroke to such a degree that does not cause
double hooking. Adjust it while checking bar tacking
stitches.
63
Work clamp pressure Increase work clamp pressure.
* The standard height of the adjustment screw is
approximately 30 mm, so tighten it further than
this.
74
Work clamp
Relation between work
clamp assembly and
sewing length Replace work clamp assembly that fits for sewing
length.
* When using knits or woven materials, replace the
parts with the –3 specification parts:
Length feed plate (for specification -3), work
clamp assembly (for knits), needle plate 1.2 (for
specification -3) -
Blunt rotary hook point Polish with buff or replace the part. -
Needle bar height and
needle bar lift amount Adjust the needle and hook timing.
1. Adjust the needle bar height to “1” on the gauge.
2. Adjust the needle bar lift amount to “2” on the
gauge.
72, 73
Rotary hook
Gap between needle and
rotary hook Adjust the gap between needle and rotary hook to
0.01 - 0.08 mm. (Adjust to as large as possible
without causing skipped stitches to occur.)
* Check that rotary hook point does not strike
needle in zigzag motion.
73