UnionSpecial 39500 MC Instruction sheet

FINES T QUALITY
STYLE
39500 MC
•
CATALOG
No.
®
LEWIS • COLUMBIA
CLASS 39500
INDUSTRIAL
SEWING
MACHINES
HI-STYLED HIGH SPEED
TWO OR THREE THREAD
HEMMER OR SERGER
DIFFERENTIAL FEED MACHINES
CHICAGO
From the library of: Superior Sewing Machine & Supply LLC

From the library of: Superior Sewing Machine & Supply LLC

August, 1969
Catalog No. 103 MC
(Supplement to Catalog No. 103 FA)
INSTRUCTIONS
FOR
ADJUSTING AND OPERATING
LIST OF PARTS
CLASS 39500
Style
39500 MC
First Edition
Copyright 1969
By
Union Special Machine Co.
Rights Reserved in All Countries
MACHINE COMPANY
INDUSTRIAL SEWING MACHINES
CHICAGO
Printed in U.S. A.
3
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IDENTIFICATION OF MACHINES
Each Union Special machine is identified by a Style number on a name plate on
the machine. Style numbers are classified as standard and special. Standard Style
numbers have one or more letters suffixed, but never contain the letter "Z".
Example: "Style 39500 MC". Special Style numbers contain the letter "Z". When
only minor chan g es are made in a standard machine~ a "Z" is suffixed to the stan-
dard Style number. Example: "Style 39500 MCZ".
Styles of machines sim il ar in construction are grouped under a Class number,
which differs from the Style number in that it contains no letters. Example: "Class
3 95 00".
APPLICATION OF CATALOG
This catalog is a supplement to Catalog No. 103 FA and should be used in con-
junction therewith. Only those parts used on Style 39500 MC, but not on Style 39500
FA are illustrated and listed at the back of this catalog. On the page opposite the
illustrat i on will be found a listing of the parts, with their part numbers~ description
and the number of pieces required. Numbers in the first column are reference
numbers only, and merely indicate the position of that part in the i llustration. Re-
ference numbers should never be used in orde r ing parts. Always use the part num-
ber listed in the second column.
This catalog applies specifically to the standard Style of machine as listed here-
in. It can also be applied with discretion to some Special Styles of machines in
Class 39500. References to directions, such as right, left~ front~ back, etc., are
given from the operator's position while seated at the machine. Operatin g di rection
of handwheel is away from operator.
STYLE OF MACHINE
Hi-Styled High Speed, Single Curved Blade Needle~ One Looper-One Spreader Two
Thread and Two Looper Three Thread Over seaming Machine. Differential Feed~
Trimming Mechanism with Spring Pressed Lower Knife, Automatic Lubricatin g
System.
39500 MC Light to medium duty~ two way combination machine, for two or three
thread blind hemming or serging small diameter light weight rayon~ s ilk, wool~
cotton~ flat and ribbed knit materials. Seam specifications 503 EFc-1~ or
505 EFd-1. Standard seam width for hemming 1I8 inch and for ser g in g 3I 16
inch. Stitch range 8 to 30 per inch. Cam adjusted main and different ial feeds.
Maximum recommended speed 7 000 R. P.M.
OILING
CAUTION! Oil was drained from machine when shipped~ so reservoir must be
filled before beginning to operate. Oil capacity of Class 39500 is si?E, ounces. A
straight mineral oil of a Saybolt viscosity of 200 to 250 seconds at 100 Fahrenheit
should be used.
Machine is filled with oil at sprin g 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.
Machine is automatically lubr i cated. No oil ing is necessary, other than keepin g
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 ed ge of base.
It is a magnetic screw desi g ned to accumulate possible foreign materials which may
have entered the crank case. It should be removed and cleaned periodically.
4
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NEEDLES
Each Union Special needle has both type and size number. The type number
denotes the kind of shank, point, length, groove, finish and other details. The size
number, stamped on the needle shank, denotes largest diameter of blade, measured
in thousandths of an inch, midway between shank and eye. Collectively, type and
size number represent the complete symbol which is given on the label of all needles
packaged and sold by Union Special.
Class 39500 machines use a curved blade needle. The standard recommended
needle for Style 39500 MC is Type 154 GAS. Below is the description and sizes
available of the recommended needle.
Type No. Description and Sizes
154 GAS Round shank, round point, curved blade, standard length, single groove,
struck groove, spotted, chromium plated and is available in sizes 022,
025, 027, 029, 032, 036, 040, 044, 049, 054.
To have needle orders promptly and accurately filled, an empty package, a
sample needle, or the type and size number should be forwarded. Use description
on label. A complete order would read: "1 000 Needles, Type 154 GAS, Size 027".
Selection of proper needle size is determined by size of thread used. Thread
should pass freely through needle eye in order to produce a good stitch formation.
Success in the operation of Union Special machines can be secured only by use
of needles packaged under our brand name, ~ . which is backed by a
reputation for producing highest quality needles in materials and workmanship for
more than three-quarters of a century.
CHANGING NEEDLES
Release pressure on presser foot by turning presser foot release bushing (AG,
Fig. 1 or 1A) and swing presser arm (U) out of position. Turnhandwheel in operating
direction until needle is at its lowest point of travel. Using hexagonal socket wrench
No. 21388AU, furnished with machine, loosen needle clamp nut about 1/4 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 and re-lock presser foot release bushing
(AG).
THREAD STAND
After thread comes from cones on cone support (A, Fig. 1 or 1A) it is brought
up through the back hole of thread eyelet (B), then down through the front hole of
thread eyelet. Next, the upper looper thread (505 STITCH only) and the needle
thread are threaded through the upper hole of tension thread guide (C)from front to
back, and then through the lower hole, from back to front. The lower looper thread
is threaded through the upper hole of the tension thread guide (C) from back to front,
through the middle hole from front to back and then through the lower hole from back
to front. All threads then continue between the tension discs (J), through tension
post slot (K) in tension post (G) and on through eyelets in front thread guide (M).
NOTE:
Refer to Fig. 1 for threading 503 stitch or Fig. 1A for threading 505
stitch.
5
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li] Tension Nut
~~ Thread Eyelet
~~ Tension Spring Fer~
II Tension Spring ---,~/ nlh~l\d:\\
[!] Tension Post
IIJ spring Shield _
OTension Discs < .
P!.ll Tension Post Slot . '...... ... --~;:::.:"
.. ••. ·-~"">"
II Tension Disc Felt . j
f1J Front Thread
I:J Lower Looper Thread
BJ Fabric Guard
D) Presser
Fig. 1
6
0
Presser Foot
~~~ Release Bushing
Top Cover
...... Needle Thread Eyelet
Upper Looper
Thread Tube Assembly
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li] Te ns ion Nut
(I Ten sio n Spring F e r ~
IJ Tension Spring~ r..-~:=-h'\.1
[!] Tension Post
IIJ spring Shield
gTension
Discs -<: .
~~ T e nsion Post Slot ·.
II Tension Disc Felt ·.
[i Tension Thread Guide
f1J Front Thread Guide
~~~ Upper Looper Thread Eyelet
I:J Lower Looper Thread Eyelet
D
Frame Looper
Thread Guide
m Presser Arm
7
Cone Support
Top Cover
M~:. Needle Thread Eyelet
Upper Looper
Thread Tube Assembly
Upper Looper
Lower Looper
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THREADING
Only parts involved in threading are shown in threading diagram (Fig. 1 and 1A).
Parts are placed in their relative positions for clarity.
It will simplify the threading of these machines to follow the recommended se-
quence of threading the lower looper first and the needle second for the 503 stitch.
The recommended sequence of threading the 505 stitch is lower looper first~ upper
looper second and the needle third.
Before beginning to thread, swing cloth plate open and turn handwheel in opera-
ting direction until needle (X) is at high position. Now release pressure on presser
foot by turning presser foot release bushing (AG) and swing presser arm (U) out of
position.
Be sure the threads, as they come from the tension thread guide (C)~ are be-
tween tension discs (J) and in tension post slots (K) in tension posts (G). The tension
posts should be positioned so the tension post slot will be at the approximate angle
for the different threads as indicated in Fig. 1 and 1A.
TO THREAD THE LOWER LOOPER
Double end of thread and lead it through the right eyelet of front thread guide
(M, Fig. 1 or 1A). Then lead thread through both eyes of lower looper thread eye-
let (R~ Fig. 1 or 1A) from right to left. NOTE: thread must pass in front of looper
thread pull-off (AF). Lead thread behind fabric guard (S) and through 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 THE UPPER LOOPER (505 STITCH ONLY)
Double end of thread and lead it through the left eyelet of front thread guide (M~
Fig. 1A). Turn handwheel until point of upper looper (W~ Fig. 1A) is all the way
to the 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 and then insert thread throu gh the eye of upper
looper from front to back.
TO THREAD THE NEEDLE
Double end needle thread and lead it through middle eyelet of front thread g uide
(M, Fig. 1 or 1A). Then turn handwheel in operating direction until needle (X) is
at its highest position. Insert needle thread from right to left, through both e yes of
needle thread eyelet (AD), under neck of top cover casting; then down throu gh hole
in top cover needle thread eyelet (AC). Thread needle from front.
THREAD TENSION
The amount of tension on the needle and looper threads is regulated by tension
nuts (D, Fig. 1 or lA). Tension on threads should be only enough to secure proper
stitch formation.
8
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PRESSER FOOT PRESSURE
Sufficient presser foot pressure to feed work uniformly
should be maintained. Should it be necessary to increase
or decrease the 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 tightening in-
creases 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 locking nut (C) so that its under surface is ap-
proximately 1I32 inch to 1I 16 inch from the top surface of
adjusting screw (B). Set cap (D) against locking nut (C).
Fig. 2
FEED ECCENTRICS
Feed eccentrics used in Style 39500 MC machines have been selected to produce
approximately 14 stitches per inch. It will be noted that the part number of the main
feed eccentric is No. 39540 B-14. while that of the differential feed eccentric is No.
39540 B-8. Minor numbers of the part symbol indicate approximately the number
of stitches obtainable when using that eccentric. Unless otherwise specified. ma-
chine will be shipped with above combination of eccentrics.
Generally speaking, differential (right hand) feed eccentric determines number
of stitches produced; main (left hand) feed eccentric is selected in relation to degree
and direction of stretch of material being sewn. or type of operation.
Following stitch number feed eccentrics are available under No. 39540 B-4. -5.
-6.-7. -8. -9. -10. -11. -12,-13. -14. -15. -16. -18,-20. -22. -24. -26. -28. -30. -32. -34.
-36,-40. Only two eccentrics are supplied with each machine. Additional eccentrics
may be ordered separately. To order an eccentric. use No. 39540 B with a minor
number suffixed to indicate number of stitches desired. Example: "39540 B-8".
Fi g. 3
ASSEMBLING AND ADJUSTING SEWING PAR TS
Before assembling and adjusting sewin g parts.
remove cloth plate. fabric guard, chip guard, upper
knife assembly~ lower knife holder assembly. hem-
ming guide assembly; then follow this suggested se-
quence.
SETTING THE NEEDLE
With throat plate assembled in position. ne edle
should center in the front end of needle slot. When
needle is at high position. needle point should be set
112 inch above throat plate (Fig. 3). To ali gn ne edle
or set the height above throat plate. mov e ne edle
driving arm (A, Fig. 3) by loosening clamp screw
(B). Remove throat plate. after needle has been set
properly and clamp screw (B) has been tightened.
At this point. insert lower looper (A~ Fig. 4) into
bar (B). With lower looper at left end of its stroke~
set looper point 3I32 inch from center of needle (Fig. 4)
using looper gauge No. 2122 5-3 I 32. Do not have lower
looper deflecting needle. Tighten nut (C). Now assem-
ble differential (front) feed dog.
9
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Fig. 4
SETTING THE REAR NEEDLE GUARD
Set rear needle guard (A, Fig. 5) 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.
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. 6)
u?til the needle springs forward from rear guard surface another . 002 - • 004 inch.
SETTING THE FRONT NEEDLE GUARD
Assemble front needle guard (C. Fig. 5). When lower
looper is springing needle off back guard. set front needle
guard as close as possible to needle without touching. Screw
(D) is used to adjust and set front needle guard. After this
setting. make sure there is no interference between needle
guard and differential feed dog.
SETTING THE UPPER LOOPER OR SPREADER
Insert upper looper (A. Fig. 7) or
upper spreader in its holder. Screw
(B) holds the upper looper or spreader
in its holder. and permits the upper
looper or spreader to be pushed in or
out. or turned around its shank. Insert
upper looper or spreader holder into
shaft, if not already in place. Screw
(C. Fig. 7) on clamp collar holds upper
looper or spreader holder in the shaft,
and allows holder to be rotated or ad-
justed laterally.
Fig. 5
Fig. 6
Preliminary Setting: When the upper looper or spreader is at
the right end of its stroke, the upper looper or spreader holder should be set to
position the upper looper or spreader shank slightly back of vertical (Fi g. 7). Top
end of the upper looper or spreader shank should extend 1I32 to 1I 16 inch above the
upper looper or spreader holder (Fig. 7).
Fig. 7
As the upper looper or spreader moves from right to left.
the point of the upper looper or the Vee notch of the spreader
should pass just behind the eye of the lower looper. with
approximately • 002 inch clearance between the upper looper
or spreader and the lower looper (Fig. 8).
Turn the handwheel until the upper looper or spreader is
at the left end of its travel. At this position. the point of the
upper looper or the lower point of the upper spreader should
extend about 5132 inch to the left of the centerline of the needle
and also be 15 I32 inch above the top of the throat plate (Fig. 9).
If resetting is necessary. do it by moving the upper looper or
spreader holder (A, Fig. 9).
10
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SETTING THE UPPER LOOPER OR SPREADER (Continued)
Fig. 8
Now
check setting to avoid inter-
ference between the upper looper or
spreader and the needle on the needle
downstroke. If needle rubs the back of
upper looper or spreader, pull the upper
looper or spreader out of its holder
slightly and rotate looper a short dis-
tance counterclockwise, looking from
left end of machine. These same ad-
justments, in opposite movement, will
reduce the clearance between the upper
looper or spreader and the needle. Re-
set to maintain dimension of Figs. 8
and 9.
SETTING THE FEED DOGS
Now assemble main (back)
feed dog (B, Fig. 10) and
chaining feed dog (C). Set
all feed dogs (A, B, C, Fig.
10) so the top surfaces of the
teeth all lie in the same
plane. This can be checked
by sighting across the teeth
with a straight edge. Now
assemble throat plate. Feed
dogs should now be leveled
with throat plate surface by
Fig. 10
Fig. 9
rotating feed tilting adjusting pin (D). This pin raises or lowers the back end of feed
bar.
The feed dogs should be set level at the time the
teeth first appear above throat plate. Screw (E) locks
feed tilting adjusting pin in place. Now set the main
and differential feed dog teeth 3/64 inch above the
throat plate, and chaining feed dog teeth flush with
surface of throat plate.
SETTING THE LOWER KNIFE
Replace lower knife holder assembly. In replac-
ing the lower knife holder assembly, tighten screw
(A, Fig. 11) so that when the face of the flange on
sleeve (B) seats against the throat plate mounting
bracket (C) a free lateral motion of the lower knife
and holder assembly is obtained when the knife is
manually pressed at its upper corner. Lower knife
(D) should be set with the cutting edge flush with the
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
tightening screw (E) against knife holder shaft.
11
Fig. 11
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SETTING THE LOWER KNIFE (Continued)
Set the desired width of trim by measuring from the right edge of the lower
knife to the needle~ lock the lower knife holder shaft with screw (E).
SETTING THE UPPER KNIFE
Replace upperknifeassembly. Clamp upperknife (F~ Fig. 11) in position, set-
ting nut (G) to hold clamp (H) in its most clockwise position against upper knife. At
bottom of its stroke~ front cutting edge of upper knife should extend not less than
1/64 inch below cutting edge of lower knife. The chain guard 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~ screw (J) should be
tightened to lock upper knife holding block (K) in place. This will simplify resetting
when upper knife is replaced.
SETTING THE STITCH LENGTH
Length of stitch is determined by the combination of
feed eccentrics used. Outer (left) eccentric (A, Fig. 12)
actuates main (rear) feed dog, while the inner (right)
eccentric (B) actuates the differential (front) feed dog •
In assemblin g feed eccentrics, be sure hubs are fac-
ing each other. Be careful not to damage shaft or key .
Tighten nut (C) securely.
To change feed eccentrics, remove nut (C) and washer
(D) from end of shaft (E). Turn handwheel in operating Fig. 12
direction until key slot in eccentric is toward the front.
Using hooked eccentric extractor (F)~ supplied with machine~ reach behind eccen-
tries as shown and withdraw eccentrics. It may be necessary to move handwheel
back and forth slightly during extraction.
If eccentrics are unusually tight fitting, in addition to removing nut ( C~ Fig. 13)
and washer (D) from shaft (E)~ it may be helpful to remove nut (G) and feed driving
connection (H). Then continue as originally suggested.
SETTING THE PRESSER FOOT
Assemble the presser foot to presser arm.
With needle in high position, swing presser arm
into sewin g 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 of
needle 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
Fig. 13 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. Retighten collar screws and clamp scr e w.
The foot lifter lever arm (A, Fig. 14) and the collar (B) s ecure the shaft. Be
sure the presser arm does not bind and rise when pres s er foot release bushing is
unlocked.
12
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Fig. 14
SETTING THE PRESSER FOOT (Continued)
Adjust lifter lever stop screw (C) so that
presser foot can be raised no higher than the
upper looper or spreader will permit; then lock
the nut (D). There should be from 1/16 to 1/8
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.
turnhandwheel until upper knife assembly reach-
es its highest position.
STARTING TO OPERATE
NOTE: Be sure machine is threaded according to threading diagram Fig. 1 or
1A. With thread tensions light. set lower looper thread eyelet (R) about horizontal
and in the middle of its front to back location.
Operate machine slowly with presser foot in place; make sure chain forms and
moves off tongue freely.
NEEDLE THREAD CONTROL (505 STITCH)
While sewing on material. check needle thread control as follows: About 60%
of needle thread required for the stitch should be drawn on needle downstroke. To
increase thread drawn on the downstroke. position needle thread eyelet (AD. Fig •
1A) farther to the rear.
LOWER LOOPER THREAD CONTROL (505 STITCH)
Set lower looper thread eyelet (R. Fi g. 1A) about horizontal and all the way for-
ward in its slot.
Frame looper thread guide (T) should be set with its eyelet approximately 1/8
inch right of lower looper (V) heel eyelet. when lower looper is at the left end of
its stroke.
UPPER LOOPER THREAD CONTROL (505 STITCH)
With material under presser foot. set upper looper thread eyelet (N. Fig. 1A)
to rest on top of lowerlooperthread eyelet (R). and back far enough so upper looper
thread is a little slack when upper looper reaches the left end of its stroke.
POSITIONING THE SQUARE EDGE (505 STITCH)
Position of lower looper thread at the edge is located by balancing needl e and
upper looper thread tensions.
To reduce amount of lower thread in the stitch. or close the edge more. increa se
lower looper thread tension.
NEEDLE THREAD CONTROL (503 STITCH)
While sewing on material. check needle thread control as follows: Usually all
needle thread is drawn on needle down stroke. At top of needle stroke. thread
should be just tight enough to feed chain off stitch ton g ue. Stitch tends to pull down
slightly if excessive thread is pulled on the up stroke. With needle at bottom of
stroke. position needle thread eyelet (AD. Fig. 1) so that needle thread cam pull-off
(AE) just contacts needle thread. To increase thread drawn on downstroke. position
needle thread eyelet (AD, Fi g. 1) farther to the rear.
13
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LOWER LOOPER THREAD CONTROL
With material under presser foot. set lower looper thread eyelet (R, Fig. 1) back
and down far enough so thread is a little slack when spreader reaches its extreme
left position. Lower looper thread eyelet (R) should be about horizontal.
Frame looper thread guide (T) should be set with its eyelet approximately 1I8
inch to the right of heel eyelet of looper (V) at the time lower looper is at extreme
left end of its travel.
THREAD TENSIONS
Before proceeding. balance both tensions to give a normal appearing stitch.
Moderate change in these tensions will not markedly effect the purl.
SPECIAL ADJUSTMENTS
SKIPPING: For occasional skipping. check and/ or adjust as outlined below:
1. Recheck lower looper - needle setting. See "Setting the Needle".
2. Recheck upper looper or spreader - lower looper crossing. See "Setting the
Upper Looper or Spreader".
3. Check clearance between needle and upper looper or spreader. See that upper
looper or spreader moves far enough left past needle.
Setting 1 and 2 should be made quite carefully. If it can be determined by
appearance that skip is definitely not a needle loop skip. reposition lower looper
thread eyelet (R, Fig. 1) by lowering it slightly and bringing eyelet holes in close
to bend in looper thread pull-off (AF). After this change, increase looper thread
tension as much as possible without distorting stitch.
CAUTION: Looper thread must. as before, be slightly slack as spreader reaches
its extreme left position, or stitch will appear tight on top side.
SETTING THE HEMMING GUIDE SUPPORT BRACKET
Make sure that lock screw (A, Fig. 15) is loose, then proceed as follows:
Assemble the hemming guide support bracket onto the lower knife support bracket
by means of screw (B. Fig. 15). With the knurled adjusting screw (C), set the edge
guide (D) so that the left side of its tip is even with and parallel to the right side of
the right feed slot in the throat plate.
When the edge guide tip is in this position. the front or leading edge should be
slightly to the right of parallel. This adjustment can be made by positioning the
stop screw (A, Fig. 16) located towards the front of the hinge block and edge guide
support bracket (E, Fig. 15).
Under normal conditions, the edge guide is spring loaded to compensate for the
differences in the material thickness. For example, as in going over seams. The
amount of movement and the pressure applied to the edge guide tip can be set by
removing lock screw (B, Fig. 16) and adjusting the screw which presses against
the spring and pin, located in the hinge block and edge guide support bracket (E,
Fig. 15). Replace lock screw and tighten securely.
14
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SETTING THE HEMIVITNG GUIDE SUPPORT BRACKET (Continued)
If movement of the edge guide is not required, then remove
lock screw (B. Fig. 16), set screw and spring; then replace
set screw and lock screw. Be sure set screw is tightened
against pin and lock screw is tightened against set screw.
FINAL ADJUSTMENT OF HEMMING GUIDE
Adjust the edge guide (D, Fig. 15) by turning the knurled
adjusting screw (C) so that the stitches are located in the
folded edge, yet do not show on the face of the fabric. At this
point re-tighten screw (A, Fig. 15) securely.
Fig. 15
Adjust the overhanging guide
(F, Fig. 15) so that the space
between its guiding edge and the
edge guide (D) corresponds with
the thickness of the material to be hemmed. Loosen set
screw (C, Fig. 16) and holding screw (D), now move
the hinge block (E) to obtain the proper distance be-
tween the edge guide and the overhanging guide. Re-
tighten screws (C) and (D). Remove lock screw (F)
and adjust stop screw that is in front of lock screw,
so that the tip of the overhanging guide is located at
the center of the edge guide vertically. Replace lock
screw (F) and tighten against stop screw.
15
Fig. 16
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I
,(..
16
.
~)~ ~ ?-
~ «
,:l
16
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The parts illustrated on pages 16 and 18, and described on this page and pag e 19
represent the parts that are used on Style 39500 MC, but not used on Style 39500 FA.
Those parts shown in phantom views and bearing no reference number are common
to Styles 39500 FA and MC.
Use Catalog No. 103 FA (Style 39500 FA) for all parts not illustrated or described in
this catalog.
Reference numbers that are inside a bracket on the picture plates and have indented
descriptions. indicate they are component parts of a complete part or assembly.
Ref.
No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
Part
No.
39592 AE-4
39592 AE-4
39592 AE-4
39520 AX
39530 E
22738
22768 B
39530
39597 F
22738
39530 B
39505 G
39540 B- 8
39540 B-14
93 A
39560 A
39508 B
39505 F
39526 AY
39526 AX
39505 H
39563 J
39556 M
22798
39556 L
605
39501 AS
22657 D-12
39501 K
22513
39532 D
39582 AR
39582 H
39582 J
Amt.
Description Req .
Looper Thread Tension Spring. for 503 stitch------ 1
Looper Thread Tension Spring. for 505 stitch------ 2
Needle Thread Tension Spring-------------------- 1
Presser Foot--------- - ------------------------- 1
Presser Foot Chain Shield------------------- 1
Screw, for chain shield---------------------- 1
Screw. for stitch tongue --------------------- 1
Hinge Spring ------------------------------- 1
Stitch Tongue, marked "DV" ----------------- 1
Screw. for chip guard ----------------------- 1
Chip Guard--------------------------------- 1
Chaining Feed Dog, marked "S". for 503 stitch ---- 1
Differential Feed Driving Eccentric--------------- 1
Main Feed Driving Eccentric--------------------- 1
Screw, for main feed dog ------------------------ 1
Upper Spreader, marked "E". for 503 stitch------- 1
Lower Looper---------------------------------- 1
Main Feed Dog, marked "F" --------------------- 1
Differential Feed Dog. for 503 stitch -------------- 1
Differential Feed Dog, for 505 stitch-------------- 1
Chaining Feed Dog. marked "U", for 505 stitch---- 1
Needle Thread Cam Pull-off --------------------- 1
Chain Cutting Knife ----------------------------- 1
Screw, for chain cutter blade ---------------- 1
Chain Cutter Blade --- --- -- - ---- - -- - ----- ---- 1
Screw. for chain cutting knife ----- --- --- ----- ---- 2
Cloth Plate------------------------------------- 1
Screw. for cloth plate ----------------------- 1
Cloth Plate Stud ---------------------------- 1
Screw. for latch spring---------------------- 2
Latch Spring ------------------------------- 1
Side Cover------------------------------------- 1
Spring ------------ - ------------------------ 1
Rivet - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 2
17
From the library of: Superior Sewing Machine & Supply LLC

42
18
36
~ 37
t! 38
From the library of: Superior Sewing Machine & Supply LLC

THROAT PLATES
6
NEEDLE GUARDS, THROAT PLATE SUPPORT BLOCK,
LOWER KNIFE PARTS AND HEMMING GUIDE ASSEMBLY
Ref.
No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
Part
No.
22559 H
39550 J
39550 K
39550 v
AS22 D
39524 AX
39524 AY
39525 E
22585 G
39525 D
90
39580 AG
88 B
22593
29481 L
39589 AH
39589 AG
22513 c
39503 L
22729 A
39589 AJ
39589 AB
73 c
HA73 B
39589 AF
222 D
22743
39589 AA
222 D
39589 AL
39568 J
79077
39589 AD
22799 B
22873 c
39589 AC
61303 D
303
39589 AK-1
39589 AK- 3/4
39589 AK-1/2
39580 E
Description
Amt.
Req.
Adjusting Screw--------------------------------- 1
Knife Pressure Equalizing Spring ----------------- 1
Spring Cover------------------------------------ 1
Lower Knife Holder ----------------------------- 1
Screw
6
for throat plate -------------------------- 1
Throat Plate, marked "CD", for 505 stitch -------- 1
Throat Plate, marked "CE
11
6
for 503 stitch -------- 1
Needle Guard
6
rear ----------------------------- 1
Screw, for locking side cover -------------------- 1
Needle Guard, front----------------------------- 1
Screw
6
for needle guard-------------------------- 2
Throat Plate Support Block----------------------- 1
Screw
6
for lower knife holder -------------------- 1
Screw
6
for hemming guide assembly -------------- 1
Hemming Guide Assembly ----------------------- 1
Holding Spring ------------------------- ----- 1
Sleeve, for edge guide ----------------------- 1
Screw, for edge guide ----------------------- 1
Edge Guide ---- --------- ---- - --------------- 1
Screw, for hemming guide stop--------------- 1
Hemming Guide Stop------------------------- 1
Hinge Block -------------------------------- 1
Set Screw, for No. 22729 A ------------------ 1
Stop Screw
6
for overhanging guide hinge block -- 2
Hemmer Guide End Plate -------------------- 1
Screw, for hemmer guide end plate ----------- 1
Screw
6
for edge guide tension spring ---------- 2
Overhanging Guide Hinge Block -- - ---- -------- 1
Screw
6
for overhanging guide----------------- 1
Pin
6
for edge guide tension spring ------------ 1
Spring
6
for edge guide tension ---------------- 1
Stop Screw
6
for edge guide------------------- 1
Edge Guide Support----------------------- - -- 1
Hinge Screw, for overhanging guide hinge block - 1
Adjusting Screw
6
for edge guide support ------- 1
Hemming Attachment Base------------------- 1
Cup Washer, for screw No. 303 -------------- 1
Screw, for edge guide support---------------- 1
Overhanging Guide
6
for 1 inch hem --------------- 1
Overhanging Guide
6
for 3/4 inch hem------------ - - 1
Overhanging Guide
6
for 1/2 inch hem-------------- 1
Throat Plate Support Block Shim------------------ 1
19
From the library of: Superior Sewing Machine & Supply LLC

'
..
0
..
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From the library of: Superior Sewing Machine & Supply LLC