Singer Sewing Machine, Instruction Manual

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Common Sewing Problems
Skipped stitches are an indication that there needs to
be an adjustment made. There are several mechanical
adjustments that can be done to correct these problems.
In order to adjust the machine properly, here are the
fundamental operations of a lock stitch sewing machine.
A shuttle hook rotates around the cage that holds the
bobbin thread under the machine. The hook passes right
next to the needle as it rises and catches the loop that is
formed in the upper thread beside the needle as it comes up.
After catching this loop, the hook then pulls the loop down
until it circles around the entire bobbin of the lower thread.
The two threads are then interlocked and a stitch is formed.
The needle continues to rise, and the “take up arm” rises
to pull the excess thread up from the bottom of the fabric.
The thread then comes up out of the cloth.
Skipped Stitches
If the machine is skipping stitches, then the hook
is not catching the thread each time it makes its pass. The
cause of this is usually either the thread is not being held
down by the fabric as the needle is withdrawn and a loop
is not being formed for the hook as it passes the needle, or
the hook may not be passing the needle at the proper time.
(This would indicate that the timing is off on the machine).
Remedies
1) Change the needle
If the needle has become dulled of slightly bent
from sewing, changing the needle would solve the problem.
KEY NO
. PART
NO.
PART NAME QTY
1
WO47 TOP PLATE 1
2 BO71 TOP PLATE SET SCREW 1
3
EO66
BOBBIN WINDER STOPPER 1
4 EO66–2 BOBBIN WINDER STOPPER SET SCREW 1
5
WO47–1
SMALL PLATE COVER 1
6
AO92
SMALL PLATE COVER SEW SCREW
BOBBIN WINDER ASSEMBLY SET SCREW
2
1
7
E070–1
BOBBIN WINDER TENSION ASS. SET NUT 1
8 EO70 BOBBIN WINDER TENSION ASS. 1
9
WO47–2
SPOOL PIN 1
10
WOO1
ARM BODY 1
11 WOO2 BED 1
12
DO97
NEEDLE BAR SUPPORT SET SCREW
THREE HOLE THREAD GUIDE SET SCREW
2
1
13 WO48 FACE PLATE 1
14
CO97 FACE PLATE SET SCREW
15 W125 STITCH LENGTH PLATE 1
16 AO75 STITCH LENGTH PLATE SET SCREW 1
17 BO10 BOBBIN WINDER SET SCREW 2
18
WO32 NEEDLE PLATE 1
19 AO52 NEEDLE PLATE SET SCREW 2
20 AO48–B SHUTTLE RACE SLIDE 1
21 WO29 THREAD GUIDE 1
22 W184–1 DIAL TENSION ASSEMBLY 1
23
WO30 BOBBIN WINDER 1
24 WO25 CRANK ROD BEARING SET BASE 1
25 WO25–1 CRANK ROD BEARING SET BASE SET SCREW 2
26 EO72 TOP PLATE SET SCREW 1
27 A117 BOBBIN WINDER RUBBER RING 1
28 W184–3 THREAD TAKE–UP/CHECK SPRING 1
29 W184–2 TENSION RELEASE PIN 1
30
AO49 SHUTTLE RACE SLIDE SPRING 1
31 A050 SHUTTLE RACE SLIDE SPRING SET SCREW 1
GROUP 1
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