D) To Disassemble And Reassemble Upper Thread Tension; Causes Of Minor Difficulties - Necchi Automatic Supernova Ultra Mark 2 User Instructions

d) To disassemble and reassemble upper
thread tension
To disassemble tension:
- Place button
cc
An (Fig.
30)
on
0.
- Pull it out so that hook
cc
B" comes out
of hole "C
».
- Turn it anticlockwise, unscrewing it from
machine.
- Disassemble parts as in Fig. 31.
----@®~@
Fig. 31
Fig. 30
Carefully clean all the sur-
faces of parts.
- Assemble parts exactly as shown in Fig. 31 and in such a way that the
• 0 n mark will be visible on button
cc
A ".
- Screw the device onto the machine (press slightly and tum it anticlock-
wise; when a click is heard, turn it in the opposite direction).
- When small hook " B " comes into contact with chrome plated plate, draw
button toward you and tum it again, bringing small hook into hole
«
C
».
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21. CAUSES OF MINOR DIFFICULTIES
Needle thread breaks
- Needle is inserted incorrectly
- Upper tension is too strong
- Machine is improperly threaded
- Thread is not suitable for fabric
- Thread has knots
- Needle eye is rough or sharp
- Needle is too fine
- Needle point is damaged, bent
or blunt
- Needle plate hole is damaged
- Machine is started at full speed
- Sewing is started with thread
take-up lever not in its highest
position
- Bobbin case is damaged, due to
being hit by needle
- Shuttle race is damaged
Needle breaks
- Fabric is pulled by hand in such
a manner that needle hits needle
plate
- Needle is bent or blunt
Lower thread breaks
- Lower thread tension is too tight
- Bobb'n not evenly filled
- Bobbin is too full and does not
rotate into bobbir, case
- Dirt or lint in bobbin case
Skip stitches
- Needle is inserted incorrectly
- Needle is bent or blunt
- Thread is too heavy for the size
of needle
- Needle is of wrong size for
thread in use
Uneven stitches
- Presser foot does not rest fully
on fabric
- Pressure of presser foot is unsuf-
ficient
~ Feed dog is set too low
- Fabric is pulled by hand
- Stitch is too short
- Needle is too fine for thread in
use.
Machine does not sew straight stitch
- The cams have not been remov-
ed
Heavy turning or jamming of machine
- A loose piece of thread has been
caught in shuttle race
- Motor belt is too tight (adjust it
by loosening the motor fasten-
ing screws)
- Machine is not lubricated
- Needle has blunt point
In case you cannot adjust the
trouble, call for a mechanic at your
local NECCHI Dealer
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