Singer 6958001 Troubleshooting guide

Service Manual and Parts List
6958001
6958002
6958003
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Each 6958 machine is ide~tified by a ~ariety number on a metal
plate on the machine.
A?PLICATIO~ OF CATALOG
This cataloa applies speci:=ically to the \'arietics o-t" machines
as listed below. Reference to directions, such as riaht, left, front,
back, etc., are given from the operator's position while seated at the
machine. Operating direction of handwheel is away from operator.
VARIETIES OF "-ili,.CHI~SS
High Speed Single Curved ~eedle, Two Looper, Three Thread, Overseaming
i'lachine, with Di f: eren t ia l Feed, Tr immina !\lechani sm v;i th Spr ina Pres sed
Lower Knife and Automatic Lubricating System.
6 9 580 0l Light to medium duty machine for seaming light to medium weight flat,
warp and ribbed knit fabrics of cotton, wool, rayon, silk or similar weight syn-
thetics where long straight seams are a primary requisite. Seam specification
504-SSa-1; standard seam ·widths 3/32, 1/8 and 5/32 inch (2.38, 3.17 and 3.97
mm); stitch range, 8-2 0 per inch; ope rat or adjustable main and differential
feeds. "\Iaximum recommended speed 7 000 R. P.M. - depending on stitch length
and t:y'}Je of operation.
6958002 Light to medium duty machine, with single row main and differential
feeds that are split at the needle, for better control v.:hen sewing curves or
irregular shaped seams on women's lingerie, robes and similar seaming and
trimming operations on light to medium weight flat, warp and ribbed knit fab-
rics of cotton, silk and similar weight synthetics. Seam specification 504-SSa-1;
standard seam widths 3/32, 1/8 and 5/32 inch (2.38, 3.17 and 3.97 mm); stitch
range, 8-2 0 per inch; operator adjustable main and differential feeds. Maxi-
mum recommended speed 7 000 R. P. :vr. - depending on stitch length and type of
operation.
6958003 Same as 6958001 except medium to heavy duty machine for seam-
ing light, medium or heavy v:eight materials. Stitch range, 8-16 per inch.
=v!aximum recommended speed 6500 R. P.M. -depending on stitch length and
type of operation.
OILING
CAUTION! Oil was drained from machine when shipped, so reservoir must be
filled before beginning to operate. Oil capacity of Class 6958 is eight
ounces. nse Sinaer Tvoe C oil or eauivalent.
Machine is filled with oil at spring cap in top cover. Oil level is checked at
sight gauge on front of machine. Red bulb on oil level indicator should show between
gauge lines when machine is stationary.
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OILING (Continued)
Machine is automatically lubricated. No oiling is necessary, other than keeping
main reservoir filled. Check oil daily before the morning start; add oil as required.
The oil drain plug screw is located at back of machine near bottom edge of base.
It is a magnetic screw designed to accumulate possible foreign materials which may
have entered the crank case. It should be removed and cleaned periodically.
NEEDLES
Class 695B machines use a curved blade needle. The standard
recommended needle for machines covered in this catalog is:
Cat. 1431
Light Set Point
(Sizes
7
to
23)
Also
available
are:
Cat.
1433
Light" Ball Point
(Sizes
7
to
21)
Cat.
1434
Medium Ball Point
(Sizes
9 to
18)
Cat.
1436
Heavy Ball Point
(Sizes
8 to
16)
CHANGING NEEDLES
Release pressure on presser foot by turning presser foot release bushing (AG,
Fig. 1) and swing presser arm (U) out of position. Turn handwheel in operating
direction until needle is at its lowest point of travel. Using hexagonal socket wrench
No. 21388 AU, furnished with machine, loosen needle clamp nut about 1I4 turn.
Again turn handwheel until needle is at high position; withdraw needle.
To replace needle, leave needle holder at high position and with the flat to the
left, insert needle in holder until it rests against stop pin. Keeping needle in this
position, turn handwheel until holder is again at its low point of travel; then tighten
nut. Return presser arm (U) to position; relock presser foot release bushing (AG ).
THREAD STAND
After thread comes from cones on cone support (A. Fig. 1 ), it is brought up
through back hole of thread eyelet (B), then down through the front hole of thread
eyelet. Next it is threaded through the upper holes of tension thread guide (C) from
front to back and then through the lower holes from back to front. It should be noted
that the lower looper thread is threaded through the tension thread guide (C), first
through the upper hole back to front, second through the middle hole front to back
and third through the lower hole back to front. All threads then continue between the
tension discs (J), through tension post slot (K) in tension post (G) and on through
front thread guide (::vi).
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[i Tension Thread Guide
~Front Thread Guide
~ lJpper Looper Thread Eyelet
I!JLower Looper Thread Eye
HFrame Looper
Thread Guide
m Presser A:rm
Fig. 1
5
I
Cone Support
_o~jl, ___ ~\_--l====
Top Cover
_..._,.Needle Thread Eyelet
Upper Looper
Thread Tube Assembly
Needle
~Upper Looper
m Lower Looper
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THREADING
Only parts involved in threading are shown in threading diagram (Fig. 1). Parts
are placed in their relative positions for clarity.
It will simplify threading this machine to follow recommended sequence of
threading lower looper first, upper looper second and needle third.
Before beginning to thread, swing cloth plate open, turn handwheel in operating
direction until needle (X) is at high position, release pressure on presser foot by
turning presser foot release bushing (AG) and swing presser arm (U) out of position.
Be sure threads, as they come from the tension thread guide (C) are between
tension discs (J) and in diagonal slots (K) in tension posts (G).
TO THREAD LOWER LOOPER
Thread lower looper thread through right eyelet of front thread guide (l\1). Then
double end of thread and lead it through both eyes of lower looper thread eyelet (R,
Fig. 1) from right to left. Note: thread must pass in front of looper thread pull-off
(AF). Lead thread behind fabric guard (S) and through eyelet hole of frame looper
thread guide (T). Turn handwheel in operating direction until heel of lower looper
(V) is all the way to the left; then thread through both eyes from left to right. Left
eye of lower looper can be threaded easily if tweezers are in left hand.
TO THREAD UPPER LOOPER
Thread upper looper thread through left eyelet of front thread guide (M). Then
turn handwheel until point of upper looper (W) is all the way left. Lead thread
through auxiliary looper thread eyelet (P) from back to front, then through both
eyes of upper looper thread eyelet (N) from left to right. Note: thread must pass in
front of looper thread pull-off (AF). After pulling up upper looper thread tube
assembly (AA), lead thread under neck of top cover casting and down through thread
tube assembly (AA). Pull thread out bottom of tube; push tube down, then insert
thread through upper looper eye from front to back.
CAUTION! Be sure upper looper thread is under lower looper thread when
passing from tube assembly to upper looper eye.
TO THREAD THE NEEDLE
Thread needle thread through middle eyelet of front thread guide (l\!I). Then turn
handwheel in operating direction until needle (X, Fig. 1) is at its highest position.
Insert needle thread from right to left, through both eyes of needle thread eyelet
(AD), und2r neck of top cover casting; then down through hole in top cover needle
thread eyelet (AC). Thread needle from front.
THREAD TENSION
The amount of tension on needle and looper threads is regulated by the tension
nuts (D, Fig. 1). Tension on threads should be only enough to secure proper stitch
formation.
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PRESSER FOOT PRESSURE
Sufficient presser foot pressure to feed work uni-
formly should be maintained. Should it be necessary to
increase or decrease amount of pressure on presser
foot, loosen lock nut (A, Fig. 2) and turn adjusting screw
(B). Adjusting screw has a right hand thread so tighten-
ing increases pressure, loosening decreases pressure.
When pressure adjusting screw (B) has been properly
set, tighten lock nut (A). With presser foot resting on
throat plate, position lockin~ nut (C) so that its under
surface is approximately 1j32 inch to 1/16 inch from
the top surface of adjusting screw (B). Set cap (D)
against locking nut (C).
Fig. 2
ASSEMBLING AND ADJUSTING SEWING PARTS
Before assembling and adjusting sewing parts, remove cloth plate, fabric guard,
chip guard, upper knife assembly, lower knife holder assembly, then follow this
suggested sequence:
SETTING THE NEEDLE
Fig. 3
With throat plate assembled in position,
needle should center in the front end of needle
slot. When needle is at high position, needle
point should be set 1/2 inch above throat plate
(A, Fig. 3). To align needle or set the height
above the throat plate, move needle driving
arm (B, Fig. 3) by loosening clamp screw (C).
Remove throat plate.
If needle thread cam pull-off (A, Fig. 4)
overlaps looper thread pull-off (B), separate by
moving looper thread pull-off back. When re-
tightening looper pull-off screw, be sure to take
up end play in needle driving arm.
At this point, insert lower looper (A, Fig. 5)
into bar (B). With lower looper at left end of its
stroke, set looper point 1/8 inch from center of
needle (Fig. 5), using loopergaugeNo. 21225-1/8.
Do not have lower looper deflecting needle. Tighten
nut (C).
Now assemble differential (front) feed dog.
SETTING THE REAR NEEDLE GUARD
Fig. 4
Set rear needle guard (A, Fig. 6) as high as possible, without interfering with
either lower looper or movement of lower knife holder, but still in position to deflect
needle forward . 002-. 004 inch. Screw (B) is used to set rear needle guard. Make
sure there is no interference between rear needle guard and lower looper.
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SETTING THE LOWER LOOPER
Now finish lower looper adjustment. As
lower looper moves to the right, its point should
be set into the needle scarf (A, Fig. 7) until the
needle springs forward from rear guard surface
another . 00 2-. 004 inch.
SETTING THE FRONT NEEDLE GUARD
Assemble front needle guard (C, Fig. 6).
When lower looper is springing needle off back-
Fig. 5 guard, set front needle guard as close as possi-
ble to needle without touching. Screw (D) is used
to adjust and set front needle guard. After this setting make sure there is no inter-
ference between needle guards and differential feed
dog.
SETTING THE UPPER LOOPER
Insert upper looper (A, Fig. 8) in its holder.
Screw (B, Fig. 8) holds upper looper in its holder
and permits it to be pushed in or out or turned
around its shank. Insert upper looper holder into
upper looper shaft, if it is not already in place.
Screw (C, Fig. 8) on clamp holds the upper looper
holder in the shaft. Locate upper looper in its holder
so that the shank extends 1 I 32 to 1I 16 inch beyond
holder (Fig. 8), for 6958001 and 002, l/16 to
3/32 inch for 6958003.
When the upper looper is at the right end of its
stroke, upper looper holder should be set to position
upper looper shank back of vertical on 6958001 and
002 (Fiq. 8).
NOTE: On 695B003, upper looper holder should
be set to position the upper looper shank about verti-
cally. Be sure on all styles, there is a clearance
between heel of looper and casting. By adjusting
looper holder in or out of upper looper shaft and by Fig. 6
turning the looper around its shank, set upper looper
Fig. 7
point to cross lower looper to the left of the 10\ver looper eye
with. 002 to . 004 inch clearance (Fig. 9).
As the upper looper moves toward the top of its stroke,
the heel of the up~e~ loo~er should pass behind the lower
looper head with 1164 to 1j32 inch clearance.
Next, turn handwheel until looper is at the left end of its
travel; check dimensions of upper looper point \Vith respect to
needle and throat plate (Fig. 1 0). If resetting is necessary, do
it by moving the upper looper holder (A, Fig. 10 ). Figure 1 0
represents the dimensional setting for 6 9 58 0 01 and o0 2.
For 6958003, the settings are 9/64 and 35164 inch. For
example, dimension 31/64 inch is increased by turning
upper looper holder counterclockwise lookina from
left end of machine; dimension 5/32 inch is increased
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SETTING THE C?PER LOOPER (Continued)
by pulling upper looper holder left, out o: upper looper shaft. After
these changes are made, it may be necessary to turn upper looper around
its shank slightly to maintain the condition shown in Fig. 9.
v.-hen the correct setting is obtained, it can be checked
quickly 2s fo~lov:s: As upper looper is moving to the right,
when upper looper eye centers on the needle, bottom of the
needle eye should be about level with top surface of upper
looper (Fig. 11) for 695B00l and 002. For 695B003,
the eyes of the upper looper and needle should
align exactly.
Check setting to avoid interference between upper loop-
er and needle on needle downstroke. If needle rubs the back
of upper looper, pull looper out of its holder slightly and
rotate looper a short distance counterclockwise, looking
from left end of machine. Reset to maintain dimensions of
Figs. 9, 10, 11.
SETTING THE FEED DOGS
Fig. 8
Set all three feed dogs (A, B, C, Fig. 12) so the top
surfaces of teeth all lay in the same plane. This can be
checked by sighting across teeth with a straight edge. Now
assemble throat plate. Feed dogs should now be leveled
with throat plate surface by rotating feed tilting adjusting
pin (D). This pin raises or lowers the back end of both
feed bars at the same time.
The feed dogs should be set level at the time teeth
first appear above the throat plate. Screw (E) locks feed
tilting adjusting pin in place. Before tightening screw (E),
press tilting adjusting pin (D) to the right to thrust against
feed bar thrust washer (F). Now set feed dogs so that teeth
rise about 3/64 inch above throat plate.
Fig. 9 Main feed drive eccentric ferrule (G, Fig. 12) adjusts
the position of main and chaining feed dogs from front to
rear by turning the eccentric to maintain the proper clear-
ance between the main and differential feed dogs and the rear of the throat plate slot.
Lock nut (H) to 19-20 inch lbs. when setting is made.
SETTING THE LOWER KNIFE
Replace lower knife holder assembly. Lower knife (A,
Fig. 13) should be set with cutting edge flush with throat
plate surface. Adjustments are made with hexagonal head
screw which holds lower knife. Lower knife is spring
pressed against upper knife, so no lateral adjustment is
necessary when width of trim is changed.
Lower knife may be secured in any position by tighten-
ing screw (B) and locking nut (C) against support bracket.
Because screw (B) also serves as latch pin for the cloth
plate latch spring, it should always be locked with nut (C)
even when screw is not tightened against lower knife holder.
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Fig. 10
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SETTING THE UPPER KNIFE
Replace upper knife assembly. Clamp upper knife (D, Fig.
13) in position, setting nut (E) to hold clamp (F) in its most
clockwise position against upper knife. At bottom of its stroke,
front cutting edge of upper knife should extend not 1E:3 s than 1/64
inch below cutting edge of lower
knife. The chain guard (G)
should be set down against the
upper knife and slightly back
from the cutting edge.
After upper knife has been
set for proper width of trim,
Fig. 11 screw (H) should be tightened
to lock upper knife holding
block (J) in place. This will simplify resetting when
upper knife is replaced.
SETTING THE STITCH LENGTH
The main and differential feed controls are in-
dependent of each other.
The right knurled knob marked "l\IAIN" is for
adjusting the main stitch length.
The left hand knurled knob marked "DIFF" is
for adjusting the differential stitch length.
The forward letter marking "L" indicates the
longest stitch length, while the most rearward letter
marking "S" indicates the shortest stitch length.
Therefore, moving the indicator pointers of the main
and differential controls rearward shortens the
stitch length. To obtain the proper stitch length, Fig. 12
set the main and differential feed dogs to have the same feed travel. AdJust accord-
ingly until the desired stitch length is obtained.
NOTE: See Page 19 for "STITCH LENGTH TABLE''.
Fig. 13
After stitch length is set and reverse differential
feed is desired, turn the differential knob to a shorter
stitch length until the desired s earn is obtained. If
differential feed is desired, turn the differential knob
to a longer stitch length until the desired seam is ob-
tained. As a precaution, after setting the- stitch length,
check the travel of the feed dogs to make sure that there
is clearance between the throat plate slots and the main
and differential feed dogs.
Locking Main and Differential Feed Travel Controls
1. Differential feed is locked by moving differential
feed lever lock to differential indicator lever after
proper stitch length is obtained and also by locking
indicator lever nut.
2. Main feed stitch length mechanism is locked by
turning down nylok screw located behind the throat
plate support block in the casting.
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Fig. 14
SETTING THE PRESSER FOOT
Assemble the presser foot to presser
arm. With needle in high position, swing
presser arm into sewing position and set the
presser foot to align needle holes (front and
back) and flat on throat plate. The front edge
of needle hole in presser foot must be aligned
with front edge ofneedle hole in throat plate.
It is also important that the bottom of the
presser foot be flat on the throat plate. If
necessary, presser foot can be realigned with
throat plate slots by shifting the foot lifter
lever shaft (H, Fig. 14). To move the shaft,
loosen collar screws (B, Fig. 14) and clamp
screw (G) and then shift the foot lifter lever
shaft to the left or right as required. Re-
tighten collar screws and clamp screw.
The foot lifter lever arm (A, Fig. 14) and the collar (B) secure the shaft. Be
sure the presser arm does not bind and rise when presser foot release bushing is
unlocked.
Adjust lifter lever stop screw (C) so that presser foot can be raised no higher
than upper looper will permit; then lock the nut (D). There should be from 1I 16 to
1I8 inch free motion of foot lifter lever before the presser foot begins to rise. This
adjustment should be made with screw (E) and locked with nut (F). Re-assemble the
chip guard, fabric guard and cloth plate. To assemble chip guard, turn handwheel
until upper knife assembly reaches its highest position.
STARTING TO OPERATE
Be sure machine is threaded according to threading diagram (Fig. 1). With
thread tensions light, set looper thread eyelets (N and R) about horizontal and in the
middle of their front to back locations. Operate machine slowly, without presser
foot in place, to make sure that chain forms and moves off the tongue freely. Swing
presser foot into position, insert material and sew slowly.
NEEDLE THREAD CONTROL
While sewing on material, check needle thread control as follows: Usually all
needle thread is drawn on needle downstroke. At top of needle stroke, thread should
be just tight enough to feed chain off stitch tongue. Stitch tends to pull down slightly
if excessive thread is pulled on the upstroke. With needle at bottom of stroke, posi-
tion needle thread eyelet (AD, Fig. 1) so that needle thread cam pull-off (AE) just
contacts needle thread.
It is desirable to adjust the needle thread pull-off eyelet well-forward (toward
the operator) to delay, slightly, the tightening of the needle thread.
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