Inspection before starting work
10
Chapter 1
SQ06
4. Inspection before starting work
Before starting work, execute inspection (including cleaning, lubrication) of each part.
Place Checking
Covers Covers might have been attached incorrectly.
Upper thread
The thread might have been passed incorrectly to each part.
The tension might have been inadequate.
The thread might have been entwined around frame/drive
system.
Under thread
The under thread (bobbin case) might have been set to
rotary hook incorrectly.
The tension might have been inadequate.
Needle
The needle might have bent.
The direction of needle might have been wrong.
The needle might have been broken.
Rotary hook (p.201)
Cleaning/lubrication might have been performed in
inadequate frequency.