Brother BAS-311G Troubleshooting, Problem, Cause, Remedy, Reference, Upper, thread, trimmed, Poor

10. TROUBLESHOOTING

Problem

Cause

Remedy

Reference

Upper

thread

is

not

Movable knife is not cutting cleanly.

Replace with a new one.

P. 95

trimmed.

Fixed knife is not cutting cleanly.

Sharpen the fixed knife or replace it

P. 95

with a new one.

Adjust the position of the shuttle race

P. 92

Movable knife is not picking up the

thread guide.

upper thread.

Adjust the needle bar lift amount.

P. 91

Movable knife is not picking up the

upper thread because the last stitch is

Refer to "Skipped stitches occur".

P. 142

being skipped.

Movable knife position is incorrect.

Adjust the position of the movable

P. 93

knife.

P. 94

Sub-tension is too weak.

Turn the sub-tension nut to adjust the

Instruction

tension.

manual

Poor

stitch

finish

on

Shuttle

race thread guide is

not

Adjust the position of the shuttle race

P. 92

underside of material.

separating the threads enough.

thread guide.

Incorrect tightening of the upper thread

Adjust the upper thread tension.

P. 89

Upper thread length is irregular.

Adjust the sub-tension.

Instruction

manual

Incorrect

tightening

of

Upper thread tension is too weak.

Adjust the upper thread tension.

P. 89

the thread

Lower thread tension is too weak.

Adjust the lower thread tension.

P. 89

Thread

take-up

spring

tension

and

Adjust the tension and height of the

P. 90

height are incorrect.

thread take-up spring.

Position

of arm

thread

guide

R is

Adjust the position of arm thread guide

P. 90

incorrect.

R.

Upper

thread

length is

Thread

take-up

spring

tension

and

Adjust the tension and height of the

P. 90

irregular.

height are incorrect.

thread take-up spring.

Sub-tension is too weak.

Turn the sub-tension nut to adjust the

Instruction

tension.

manual

Fixed knife is not cutting cleanly.

Sharpen the fixed knife or replace it

P. 95

with a new one.

Sewing

machine does

Check if the machine head switch cord

Instruction

not operate

when

the

is disconnected.

manual

power is turned on and

the

foot

switch

is

Machine head switch does not work.

Adjust the position of the machine head

P. 88

depressed.

switch.

If the machine head switch is

malfunctioning, replace it with a new

one.

BAS-311G, BAS-326G 143