UnionSpecial 39500GB Instruction sheet

Fl NEST 0 UAUTY
STYLES
39500GB
39500GC-
045
CATALOG
No.
103GB
®
INDUSTRIAL
SEWING
L EWIS • CO L UMB I A
MACHINES
'--
\ -- 0
\_
CLASS 3.9 500
~
HI-STYLED HIGH SPEED
TWO NEEDLE DIFFERENTIAL FEED
TOE CLOSING MACHINES
MACHINE COMPANY
CHICAGO
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Catalog No. 103 GB
(Supplement to Catalog Noo 103 FA)
INSTRUCTIONS
FOR
ADJUSTING AND OPERATING
39500 GB
LIST OF PARTS
CLASS 39500
Styles
39500 GC-045
First Edition
Copyright 1967
By
Union Special Machine Coo
Rights Reserved in All Countries
MACHINE COMPANY
INDUSTRIAL SEWING MACHINES
CHICAGO
P r i n t e d in U. S• A •
2
July, 1972
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IDENTIFICATION OF MAACHINES
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 GB". Special Style numbers contain the letter
11
Z". When
only minor changes are made in a standard machine, a
11
Z" is suffixed to the stan-
dard Style number. Example: "Style 39500 GBZ".
Styles of machines similar in construction are grouped under a Class number
which differs from the Style number in that it contains no letters. Example: "Class
39500".
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 Styles 39500 GB and GC-045, but not
on Style 39500 FA are illustrated and listed at the back of this catalog. On the page
opposite the illustration 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 ill us-
tration. Reference numbers should never be used in ordering parts. Always use the
part number listed in the second column.
This catalog applies specifically to the standard Styles of machines as listed
herein. 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. Operating direction
of handwheel is away from operator.
STYLES OF MACHINES
Hi-Styled High Speed. Two Curved Blade Needles, One Looper, One Spreader,
Three Thread Overseam.ing Machines. Differential Feed, Trimming Mechanism
with Spring Pres sed Lower Knife, Automatic Lubricating System.
39500 GB Light to medium duty machine for closing the toe sections of women's
seamless nylon hosiery. Seam specification 5 21-SSa -1. Standard seam widths
approximately 1/8 and 5/32 inch from left needle. Stitch range 20-100 per inch.
Cam adjusted main and differential feeds. Maximum recommended speed 7000
R. P.M.
39500 GC-045 Light to medium duty machine for closing the toe sections of men's
hosiery and socks. Seam specification 521-SSa -1. Standard seam width approx-
imately 3/16 inch from left needle. Stitch range 20-100 per inch. Cam adjusted
main and differential feeds. Maximum recommended speed 7000 R. P. M.
OILING
CAUTION! Oil was draiued from machine when shipped, so reservoir must be
filled before beginning to operate. Oil capacity of Class 39500 is sia ounces. A
straight mineral oil of a Saybolt viscosity of 90 to 125 seconds at 100 Fahrenheit
should be used.
Machine is filled with oil at spring cap in top cover. Oil level is checked at
sight gauge on front of machine. Red tip of oil level indicator should show between
gauge lines when machine is stationary.
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.
3
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OILING (Continued)
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 period-
ically.
NEEDLES
Each Union Special needle has both type and size number. The type number de-
notes 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 nee-
dles packaged and sold by Union Special.
Class 39500 machines use a curved blade needle. The standard recommended
needle for the machines covered in this catalog is Type 154 GCS. Below is the des-
cription and sizes available of the recommended needle.
154 GCS
Description and Sizes
Slabbed shank., round point, • 046 inch double slab., curved blade.,
standard length., double groove., struck groove, spotted., chromium
plated and is available in sizes 022, 025, 027., 029., 032.
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:
11
1000 Needles, Type 154 GCS., Size 025".
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 Gan be secured only by use
of needles packaged under our brand name., ~ .~ which is backed by a re-
putation 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 lA) and swing presser arm (U) out of position. Turn handwheel in opera-
ting direction until needles are at their lowest point of travel. Using hexagonal
socket wrench No. 21388 AU., furnished with machine, loosen needle clamp nut
about 1/4 turn. Again turn handwheel until needles are at high position. Withdraw
needle.
To replace needles, leave needle holder at high position and with the flats to
the left, insert needles in holder until they rest against stop pin. Keeping needles
in this position., turn handwheel until holder is again at its low point of travel; then
tighten nut. Return presser arm (U) to position; re-lock presser foot release bush-
ing (AG).
THREAD STAND
39500 GB ONLY
After thread comes from cones on cone support (A., Fig. 1) it is brought up
through the back hole of thread eyelet (B), then continues between tension disc felts
(L)., through tension post slot (K) of tension post (G)., and down through front hole
of thread eyelet.
4
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THREAD STAND (Continued)
39500 GC-045 ONLY
After thread comes from cones on cone support (A., Fig" lA) it is brought up
through the back hole of thread eyelet (B), then down through the front hole of
thread eyeleto
Now .. on all styles the upper looper thread and the left needle thread is thread-
ed through the upper holes (left and middle respectively) of tension thread guide (C.,
Fig. 1 or lA) from front to backo Then through the lower holes from back to fronto
The right needle 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 fronto
All threads then continue between the tension discs (J)., through tension post
slot (K) in tension post (G) and on through front thread guide (M).
THREADING
Only parts involved in threading are shown in threading diagrams (Fig" 1 and
lA)o Parts are placed in their relative positions for clarityo Refer to Figo 1 for
threading of Style 39500 GB or refer to Figo lA for threading of Style 39500 GC-045o
It will simplify the threading of these machines to follow the recommended se-
quence of threading the upper looper first .. the right needle second and the left nee-
dle third. Complete the full threading of one before proceeding to the next one.
Before beginning to thread, swing cloth plate open .. turn handwheel in operating
direction until needles {X) are in high position. Release pressure on pr~~sser foot by
turning presser foot release bushing (AG); and swing presser arm (U) out of posi-
tion.
Be sure the threads.. as they come from the tension thread guide (C) are be-
tween tension discs (J) and in tension_post slot (K) in tension post (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 lAo
TO THREAD UPPER LOOPER
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 righto NOTE: Thread must pass in
front of looper thread pull-off (AF). After pulling up upper looper thread tube
assembly (AA).. lead the thread under neck of top cover casting and down through
thread tube assembly (AA). This is easily accomplished by using the forked end of
the threading wire, supplied with each machineo Pull thread out bottom of tube
using hooked end of tweezers., also supplied with each machine. Push tube down ..
and then insert thread through upper looper eye from front to back.
CAUTION! Be sure upper looper thread is under the needle threads when passing
from tube assembly to upper looper eyeo
TO THREAD NEEDLES
Turn handwheel in operating direction until needles (X) are at their highest
position. Insert both needle threads from right to left., through BOTH eyes of nee-
dle thread eyelet (AD)., under neck of top cover casting and then down through holes
in top cover needle thread eyelet (AC). The right needle thread should be threaded
in the right hole and the left needle thread through the left hole of the top cover
needle thread eyeleto Thread needles from the fronto
5
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li]Tension Nut
(IT e nsi on Sprin g ~ / tv
Fe rrul e ~
IJTension Spring~~..-~~._,,,
[!]T ension Post~
I::Jspring Shield .... -::--~ ?;
OT ension Di scs·< ./
[I Tension Post Slot.. -- .. .
nTension Disc Fe lt ··.. ·.
f!] Front Thr ead Guide
~~Auxiliary Lo oper Thr ea d Eyelet
~Upper Loop er Thread Eyelet
Fig . 1
~~~~
(;]Tension Nut
~~Tension Sprin g ~..-.!~~:i.l
Ferrule
IITension Spring
[!]Tension Post
DTension Discs .. _
~~Tension Post Slott · 'liiiii · · ;;~~ ·- ~ - ~~.,...
IITension Disc Felt
•--- -FJCone Support
Upp er Looper
Thread Tube Ass embly
aLow er Spr ea der
£.t Needle~ /
6
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m Tension Nut
gTension Spring F e r~
OTension Spring~~~~ '"
[!lT e nsion Post
ll)spring Shield
n Tension Discs · ....
(3 Tension Post Slot :
n Tension Disc Fe lt · ..
[i Tension Thread Gu de
~Front Thread Guide
~Upper Looper Thread Eyelet
m Presser Arm
Fig . lA
7
Presser Foot
..-- · ... ~m~ Release Bushing
Top Cover
_.....,,..Needle Thread Eyelet
Upper Looper
Thread Tube A3sembly
~::;.J-,Iof"\"
- ~Upper Looper
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THREAD TENSION
The amount of tension on the needle and looper threads is regulated by three
tension nuts (D, Fig. 1 or 1A). Tension on threads should be only sufficient to se -
cure proper stitch formation.
PRESSE R FOOT PRESSURE
Sufficient p resser foot pressure to feed work un iform ly
should be maintained. Should it be necessary to i ncrease or
decrease amount of pressure on presser foot~ loosen l ock
nut ( A~ Fig . 2) and turn adjusting screw (B). Adjusting
screw has a right hand thread, so tightening increases
pressure ~ loosening decreases pre ssur e. VVhen pressure
adjusting screw (B) h as b een properly set , tight en lock nut
(A). VVith presser foot resting on throat plate~ position
locking nut (C) so that its under surface is approximately
1I32 inch to 1I16 inch from the top surface of adjusting
screw (B). Set cap (D) against locking nut (C).
FEE D ECCENTRICS
Feed eccentrics used in th e 395 00 GB machine have
Fig. 2
been se l ec ted to produce approximately 80 stitches per inch . On the 39500 GC ma -
chine, eccentr ic s hav e been selected to produce approximately 35 stitches per inch .
It will be noted on the 39500 GB machine that the part number of the main feed
eccentric is No. 39540 B- 100, while that of the differential feed eccentric is No .
3954 0 B- 70. Mi n or numb ers of the part symbol indicate approximately the number
of st itches ob tain able when using that eccen t ric . Unless otherwise specified , the
395 00 GB machine will be shipped wi th above combination of eccentrics . The 395 00
GC machine will be shipped with No. 39540 B- 60 main feed eccentric and No . 39540
B- 30 differe nti al feed eccen t ric .
G
ene rally sp eaking, differen ti al (ri ght hand) feed eccentr i c determines number
of stitches produced. Main (l eft hand) f eed ecce ntric is sel ected in relation to de-
gree and direction of stretch of material being sewn , or type of operation .
Following stitc h number feed eccentrics are available under No. 3954 0 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 , 50, 60, 70 ~ 1 00 .
Only two eccentrics are supplied with each m ac hin e. Additional eccentrics may be
ordered separately . To order , use No . 3954 0 B with a minor number s u ffixed to
indicate number of stitches desired. Exampl e:
11
39540 B -1 00
11
•
A SSE MBL I NG AN D AD JUSTING SE VV I NG PARTS
Before assembling and ad j ust in g sewing par ts, remove cloth pl ate, fab ric
guard , chip guard, upper knife assem bl y, lower knife holder assemb ly . Then, fol -
l
ow th is suggested sequ e nc e:
SETT ING THE NEEDL E
VVith throat plate assembled in position , needles should
cente r in the front end of needle slot . VVhen need l es are at
h igh position, th e need le points should be set 1 5132 inch a-
b
ove th e throat plate (Fig. 3) for Style 39500 GC - 045 . For
Style 395 00 GB the n eed le po int s should be set 7116 i nch a-
bo ve the throat plat e. To alig n need le or set the height above
th e throat pl ate, move needle driving arm (A, Fig . 3) by lo o-
sening clamp scr ew (B ). Remove throat plate.
8
Fig . 3
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SETTING THE NEEDLE ( Continued)
At this point, insert lower spreader (A, F i g. 4) into
bar (C). With lower spreader at the left end of its str oke ,
set th e spreader point 1 18 inch from center of left need le,
using looper gauge No . 21225 G- 118 . Do not have lower
spr eader d eflec ting the needles . Tighten nut (B).
Now assembly diff e rentia l (front) feed dog .
SETT I NG THE REAR NEED LE GUARD
Set rear needle guard (A, Fig . 5) as
high as possible , wi tho ut interf ering with
either lower spreader or movement of
lower knife holder , but still in position to
deflec t needle forward • 002 to • 004 inch .
Fig . 4 Screw (B) is used to s et the rear nee dle
guard . Make sure t here is no interference
between the rear needle guard and lower spreader.
F i g. 6
SETT I NG THE LOWER SPREADER
Now , finish lower spreader ad j ustment.
As spreader moves to the r i ght , its poin t
should be set into the needle scar fs (A, Fig . 6)
until needles spr in g forward from rear guard
surfac e another • 002 to • 00 4 inch .
SETTING THE FRONT NEEDLE GUARD
F ig . 5
Assemble front needle guard (C, Fig . 5) . Whe n lo w er
spreader is springing needle off backguard, set the front needle
guard as close as possible to need les wit h out touchi ng. Screw
(D) is used to adjust and set front needle guard . Af ter this set -
ting, make sure there is no interfer e nce between the needle
guards and differential feed dog.
SET TIN G THE UPP ER LOOPER
Insert upper looper (A, Fig . 7) in its hold er . Screw (B) ho l ds upper looper in
its holder and permits it to be pushed in or out, or turned arou nd its shank . I nsert
upp er l ooper holder in to upper loop er s h aft (if not al ready in place ). Screw (C) on
th e clamp h olds th e upper looper hold er in th e sha ft . L oca t e
u
pper loop er in its holder so that the shank extends 1I 64 to 1I32
inch beyond holder (Fig. 7).
Fig. 7
When the upper looper is at the right end of its stroke ,
u pper looper h older sh oul d be set to p osition upp er l ooper
shank slightly back of vertical .
Next, turn the h andwheel until looper is at the left en d of
it s travel. Ch eck the di mensions of the upper looper point wi th
r
espect to needle and throat plate (Fig . 8) and the following
di mensions ; dis t an ce from centerline of left needle to point of
loop er should be approximately 5132 inch and dis tanc e from
throat plate to point of looper should be approximately 15 I32
in ch on Style 3950 0 GC - 045 machine. ( Fig . 8) .
9
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SETTING THE UPPER LOOPER (Continued)
NOTE: For Style 395 00 GB, the dimensional setting of the upper
looper point with respect to the center of the left is also 5I32 inch,
but the se t ting of the upper looper point with respect to the throat
plate is approximately 7I 16 inch. If resetting is necessary, do so
by moving the upper looper holder (A, Fig. 8). Figure 8 repre-
sents the dimensional setting for Style 39500 GC - 045.
When the correct setting is ob tained, it
can be checked quickly as follows: As upper
looper is moving to the right, wh en upper loo-
per eye centers on the right ne ed le, the eyes
of the upper looper and right needle should
align (Fig. 9).
Check setting to avoid interference be -
Fig. 8
tween upper looper and needles on needle down stroke. If needles
rub the back of upper looper, pull looper out of its holder slightly
and rotate a short distance counterclockwise, looking from left
end of machine. Reset to maintain dimensions suggested a bove
and in Figs. 8 and 9.
Fig. 9
SETTING THE FEED DOGS
Assemble and set the differential feed dog (A, Fig.
so that top surfaces of the feed surfaces all lay in the
ch e cked by sighting across feed -
ing surface with a straight edge.
Feed surfaces should now be le-
veled with the throat plate surfaces
by rotating fe ed tilting adjusting
pin (D). This pin raises or lo wers
the back end of both feed bars at
the same time.
The feeding surfaces should
be set level at the time feeding
surface first appears above the
throat plate. Screw (E) locks feed
tilting adjusting pin in place.
Now, set feeding surfaces so
they rise above 3164 inch above
throat plate.
10) and main feed dog (B)
same plane. This can be
Fig. 10
Set chaining feed dog (C) level
with top of throat plate when feed dog is at top of its travel.
SETTING THE LOWER KNIFE
Replace low er knife holder assembly. Lower knife (A, Fig. 11) should be set
with cutting edge flush with throat plate surface. Adjustments are made with hexa-
gonal 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 .
10
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SETTING THE LOWER KNIFE (Continu ed)
Lower knife may be secured in any position by tight -
ening screw (B) and locking nut (C) against support brac-
ket. Because screw (B) also serves as l atc h pin for the
cloth plate latch spring, it should always be locked wi th
nut (C) even when screw is not tightened against lower
knife holder.
SETTING THE UPPER KNIFE
Replace upper knife assembly. Clamp upper knife
(D), Fig. 11) 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 less than 1 /64 inch below cutting edge
of lower knife. The chain guard (J) should be set down
against th e upper knife and slightly back from the cutting
edge.
Fig. 11 After upper knife h as been set for proper width of
trim, screw (G) should be tightened to lock upper knife
holding block (H) 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 (ri gh t)
eccentric (B) actuates the differential (front) feed dog.
In assembling feed eccentrics , be sure hubs are
facing each. 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 direction un - Fig. 12
til key slot in eccentric
is toward front. Using hooked eccentric extractor
(F), supplied with machine, reach behind eccen -
trics as shown and withdraw eccentr ics. It may
be necessary to move handwhee l back and fo rth
slightly during extraction.
Fig. 13 If eccentrics are unusually tight fitting , in
addition to removing nut (C) and washer (D) (Fig.
13 from shaft (E), it may be helpful to remove nut (G) and feed driving connection
(H). Then continue as originally suggested.
11
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SETTING THE PRESSER FOOT
Assemble the presser foot to presser arm . With ne edle 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. Th e front edge of needle hole in presser
foot must be aligned wi th front edge of needle hole in throat plate. It is also impor -
tant 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 lev er
shaft (H, Fig . 14). To move the shaft , loosen
collar screws (B, Fig. 14) and clamp screw
(G) a nd th en shift the foot lifter lever shaft
to th e left or rig ht as required. Re - tighten
collar screws a nd clamp screw.
The foot lifter l ever arm (A, Fig. 1 4)
and the collar (B) secure the shaft. Be sure
th e 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 1/ 16 to 1/ 8
inch free motion of foot lifter lever before
th e presser foot begins to rise. This ad just - Fig. 14
me nt should be made with screw (E) and lock -
ed with nut (F). Re - assemble the chip guard, fabric guard and cloth plate. To
assemble chip guard, turn handwhe el until upper knife assembly reaches its highest
position.
STARTING TO OPERATE
Be sure m ac hine is thr eaded according to diagram for your style of machine
( ei ther Fig . 1 or Fig. 1 A). With thr ead tensions ligh t, set upper looper thread eye -
let (N, Figs. 1 or 1A) about hori zonta l and back in its front to back location.
Op era te machine slowly, without presser foot in place, to make sure that cha in
forms and moves off th e tongu e freely. Swing presser foot into position, insert
material, and sew slowly.
NEEDLE THRE AD CONTROL
While sewing on material, check needle thr ead control as follows:
FOR 39500 GC - 045
About 60% of needle thr ead is drawn from cones on needle down stroke. The
remaining 40% is dr aw n on the upstroke . With needle at bottom of stroke, position
needl e thread eyelet (AD , Fig. 1A) so that needle thread cam pull-off ( AE ) just con-
tacts needle thread .
The eye let is adjusted correc tl y in its front to back position when the desired
stitch is obtained with the least amount of needle thread tension when sewing over
the complete speed range.
FOR 39500 GB
Usually, all needle thr ead is drawn on needle down stroke. At top of n eedle
stroke, thread should be just tight enough to feed chain off stitch tongue. Needle
thr eads t end to pull down slightly if excess i ve thread is pulled on th e up stroke.
With needles at bottom of stroke, position needle thread eyelet (AD, Fig. 1) so that
the needle thread pull- off (AE) draws th e proper amount of needl e thread to satisfy
the above conditions .
12
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UPPER LOOPER THREAD CONTROL
During needle down stroke~ forward stroke of looper thread pull-off (AF~ Fig. 1
or Fig.. 1A) will draw upper looper thread through the tension.. When normal amount
of looper thread is drawn~ upper looper thread will have almost all slack taken up
as looper thread pull- off reaches its most rearward position.
FOR 39500 GC-045
If upper looper thread has a loose appearance in the seam~ move the upper
looper thread eyelet (N~ Fig. 1A) forward and raise slightly. If~ however, the eye-
let is raised too high and moved too far forward~ the looper thread will tend to
break excessively--even with a minimum amount of looper thread tension applied.
FOR 39500 GB
If upper looper thread has loose appearance in the seam~ move the upper loo-
per thread eyelet (N~ Fig. 1) forward slightly. If, however., the eyelet is too far
forward, the looper thread will tend to break excessively- ... even with a minimum
amount of looper thread tension applied.
CAUTION! Do not try to obtain a tight looper thread appearance on the seam by
carrying high tensions.
POSITIONING THE PURL TO OBTAIN A FLAT SEAM
If the purl is at the top edge of the garment., the seam can be opened into a near
butted appearance. If, however, the purl is under the edge~ a less flat and tighter
seam results when opened.
FOR 39500 GC-045
Raising and bringing the upper looper thread eyelet (N~ Fig. 1A) forward
causes less thread to be pulled from the cones as the looper travels to the top of its
stroke and causes the purl to form more on the top of the edge. If the eyelet is
raised and brought too far forward, however., the thread becomes too tight, result-
ing in looper thread breakage. With a reasonable amount of looper thread tension
to insure a flexible chain, the looper thread eyelet should be adjusted to position
the purl is desired.
FOR 39500 GB
Moving the needle thread eyelet (AD, Fig. 1) back causes less thread to be
pulled from the cones as the needles travel to the top of their stroke and causes the
purl to form more on the top of the edge. If the eyelet is moved back too far, how-
ever, the threads become slack at the top of the stroke and the chain will not feed
off the throat plate tongue. With a reasonable minimum needle thread tension to in-
sure uniformity, the needle thread eyelet should be adjusted to position the purl as
desired.
THREAD TENSIONS WITH RESPECT TO STITCH
FOR 39500 GC-045
The needle thread tension required is a function of needle thread and the rna-
terial being sewn. In general., upper looper thread tension should be set as high as
possible without causing the needle threads to be pulled too far over the top of the
seam and low enough to prevent looper thread breakage.
FOR 39500 GB
The needle threads and looper thread tensions should be set at a minimum to
insure uniformity of stitch. NOTE: Tension applied to the threads at the thread stand
tension disc felt (L, Fig. 1) should only be enough to prevent the threads from be-
coming slack between these tension pads and the tension discs mounted on the ma-
chine. All controlling tension settings to insure uniformity of stitch should be ob-
tained by varying the tensions at the tension discs, which are mounted on the
machine.
13
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14
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The parts illustrated on the preceding page and described on this page represent the parts used on
Styles 39500 GB and 39500 GC-045, but not used on Style 39500 FA.
Parts shown in phantom views and bearing no reference numbers are common to Styles 39500 FA,
39500 GB and 39500 GC-045.
Use Catalog No. 103 FA for all parts not illustrated or described here.
Reference numbers that are inside a bracket or box on the picture plate and have indented descriptions,
indicate they are components of a complete part or assembly.
Ref.
Part
Amt.
No. No.
Description Req.
1
39552 G
Needle Driving Arm----------------------------------------- 1
2
22596 E
Screw, for needle driving arm ---- - -------- ---- --- ----- -- 1
3
50-774 Blk
Stop Pin, for needle ------------------------------------ 1
4
154 GCS Needle ---------------------------------------------------- 2
5
39563 p
Needle Thread Pull-off, for Style 39500 GB-------------------- 1
39563 G
Needle Thread Cam Pull-off, for Style 39500 GC-045 ----------- 1
6
39592 AE-1
Needle Tension Spring, for Styles 39500 GB, GC-045 ----------- 2
39592 AE-1
Looper Tension Spring, for Style 39500 GB -------------------- 1
39592 AE-2
Looper Tension Spring, for Style 39500 GC-045 ---------------- 1
7
39592 E
Pad, for tension post mounting bracket ----------------------- 1
8
39520 AB
Presser Foot, for Style 39500 GB ---------------------------- 1
39520 AC
Presser Foot, for Style 39500 GC-045 ------------------------ 1
9
39530 p
Chip Guard--------------------------------------------- 1
10 22738
11
39597 AB
Screw, for chip guard ----------------------------------- 1
Stitch Tongue, marked
11
EK
11
- ---------------------------- 1
12
22768 B
Screw, for stitch tongue and hinge spring------------------ 1
13
39530 G
Hinge Spring------------------------------------------- 1
14
22738
Screw, for chain shield---------------------------------- 1
15 39530 R
Chain Shield, for presser foot No. 39520 AC--------------- 1
39530 s
Chain Shield, for presser foot No. 39520 AB--------------- 1
16
39556 J
PresserArm----------------------------------------------- 1
17 39505 E
Chaining Feed Dog, 20 teeth per inch, for Style 39500 GC-045 --- 1
18
39526 AC
19
39505 AC
Differential Feed Dog, 22 teeth per inch, for Style 39500 GC-045- 1
Main Feed Dog, marked
11
AM
11
, 22 teeth per inch, for Style
39500 GC-045--------------------------------------------- 1
20
22797 A
21 39505 AB
22 39526 AB
23
39524 AB-1/8
39524 AB-5/32
24
39524 AC
39528 AC
Screw, for chaining feed dog, for Style 39500 GC-045----------- 1
Main Feed Dog, marked
11
AG
11
, rubber, for Style 39500 GB------ 1
Differential Feed Dog, rubber, for Style 39500 GB ------------- 1
Throat Plate, marked
11
AX-1/8
11
, for Style 39500 GB-1/8 ------- 1
Throat Plate, marked
11
AX-5/32, for Style 39500 GB-5/32 ------ 1
Throat Plate, marked
11
AV
11
, for Style 39500 GC-045 ----------- 1
Throat Plate, marked
11
AY
11
, for Style 39500 GC-060 ----------- 1
25 39525 J
Needle Guard, rear----------------------------------------- 1
26 39525 H
Needle Guard, front----------------------------------------- 1
27
29477 KJ
Crankshaft and Needle Driving Arm Crank Assembly----------- 1
28
51-228 Blk
Vent Plug---------------------------------------------- 1
29
39516-625
Needle Bearing, .0625 inch diameter--------------------- 28
39516-626
Needle Bearing, .0626 inch diameter--------------------- 28
39516-627
Needle Bearing, .0627 inch diameter--------------------- 28
30
30-92 Blk
\Vood Plug--------------------------------------------- 1
31
C067 E
Cork Plug--------------------------------------------- 1
32
40-46
\Vasher------------------------------------------------ 1
33 258
Nut--------------------------------------------------- 1
34
39541 A
Feed Driving Eccentric Key ------- ---------------------- 1
35 29477
JN
Needle Driving Arm Crank and Connecting Rod Assembly--- 1
36
22587 M
Screw, for needle driving arm connecting rod --------- 2
37 22596 G
Screw, for needle driving arm crank----------------- 1
38
39540 B-100
Main Feed Driving Eccentric, for Style 39500 GB-------------- 1
39540 B-60
Main Feed Driving Eccentric, for Style 39500 GC -------------- 1
39
39540 B-70
Differential Feed Driving Eccentric, for Style 39500 GB-------- 1
39540 B-30
Differential Feed Driving Eccentric, for Style 39500 GC -------- 1
40 22569 D
Screw, for needle thread eyelet------------------------------ 1
41
39563 N
Needle Thread Eyelet, for Style 39500 GB--------------------- 1
39563 H
Needle Thread Eyelet, for Style 39500 GC-045------ ----------- 1
42
39501 DD
Cloth Plate, for Style 39500 GB------------------------------ 1
39501 D
Cloth Plate, for Style 39500 GC ------------------------------ 1
43
39578 TB
Chip Guard, for Style 39500 GB------------------------------ 1
39578 u
Chip Guard, for Style 39500 GC ------------------------------ 1
44 39563 R
Top Cover Needle Thread Eyelet, for Style 39500 GC-045------- 1
45
39563 X
46
39560 B
Top Cover Needle Thread Eyelet, for Style 39500 GB----------- 1
Lower Spreader, for Styles 39500 GB, GC-045 ---------------- 1
15
From the library of: Superior Sewing Machine & Supply LLC

16
From the library of: Superior Sewing Machine & Supply LLC

Ref.
No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
*21
t
t
t
22
23
24
25
26
27
28
29
THREAD STAND AND MISCELLANEOUS TOOLS
Part
No.
21113 F
21104 v
69 s
21130 W-3
22650 CB-4
22650 CE-6
21104 AA
652 J- 24
652 J-16
WA9A
651 A-16
SC333 A
39592 w
660-264
116
39599 A
660-240
21388 AU
21227 BF
421 D-34
21202
28604 R
39595
21113 G
22565 c
39592 D
109
39592 E
51292 F-1
107
108
Description
For Style 39500 GC-045 Only
Amt.
Req.
Thread Stand Eyelet and Support Rod----------.... 3
For Styles 39500 GB and GC-045
Pad, for thread cone ------------------------- 3
Spool Pin-------------------------------- .... -- 3
Cone Support-------------------------------- 1
Screw, for thread stand eyelet------------ 3
Screw, for thread stand rod -------------- 1
Thread Stand Rod ----- ------- - - ---- --- ------- 1
Washer------------------------------------- 1
Washer------------------------------------- 1
Lock Washer -------------------------------- 1
Nut ---------------------------------------- 1
Wood Screw, round head #9 x 5/8 inch long----- 2
Tension Post Bracket, for mounting on
tableboard--------------------------------- 1
"S" Hook for treadle chain------------------- 2
~
Wrench~ for 9/3 2 inch nuts --- -------- --- -- --- 1
Threading Wire ------ -- ----- - -- ------ ------- 1
Thread Tweezers ---------------------------- 1
Socket Wrench, for 3/8 inch nuts holding feed
eccentrics--------------------------------- 1
Cam Extractor ---- ----- --- --- ---- --- -------- 1
Treadle Chain~ for presser foot lifter --------- 1
Screwdriver, 3/16 inch diameter, 9 3/8 inches
overall------------------------------------ 1
Container of Oil~ 16 ounces, Spec. 83---------- 1
Isolators, rubber---------------------------- 4
For Style 39500 GB Only
Thread Stand Eyelet and Support Rod ---------- 3
Screw, for tension post ------------------ 1
TensionPost-------------------------------- 3
Tension Disc (inverted)----------------------- 6
Tension Spring Pad, felt --------------------- 6
Tension Spring ------------------------------ 3
Tension Post Ferrule ------------------------ 3
Tension Post Nut ... --------------------------- 3
Not furnished with machine.
Not shown on picture plate ..
17
From the library of: Superior Sewing Machine & Supply LLC

Helpful, author it at ive information on the most effi-
ci ent types of equ ipm ent fo r mak ing v ir tually any
machine sewed artic le is available from Union Special's
Sales
Promotion Department. Among the many inter-
esting, il l ustrated bu lletin s that are available without
obligation are the fo ll owing:
No . 240, "Men's, Wome n's, Chi ld ren's Footwear"
No. 249, "Rainwear"
No. 250, "Men's Dress Shirts"
N o. 251, "Service Shirts and P ants"
No. 252, "M e n's Shorts and Pajama s"
N o. 253 , "Overalls, Covera ll s, and Dungarees"
No. 254, "M e n' s K nit Underwear "
No. 256 , "Knit Outerwear"
No . 259, "Men's Sports Shirts"
No. 260, "Work Gloves"
No. 262 , " Cot ton, Bur lap, Jut e, a nd Mu lti wa ll Paper
Bags"
No. 263, "Men's Cl oth ing"
No. 264, "Men's Women ' s, Children's J ackets"
No. 265, "Women's Wear"
No. 266, " Women 's Wear And High Fashion"
No. 26 7, "Corsets, Girdles , Br assieres"
No. 268, "Ch ild ren 's Wear"
No. 269, "Mattresses, Slip Covers, Furniture
Upholstery"
No. 271 , "Awnings, Ca no pi es, T ~n t s, Tarp s"
No. 273, " Curtains & Drapes"
No. 610 , "Kiipp-it"
No. 710, "MCS ForMat ion Unit"
No . 730, "M CS A utomati c Dual Underfront Shir t
Hemmer"
No. 740, " MCS Automat ic Rib-Knit Cuff Machine "
No. 750, "Fus in g Pre sses "
No. 1100, "L ewis Blindstitch, Cha in s titch, Lock·
sti tch, Machines"
No. 110 5, "Button Sewer s- Ti cket Ta cke r s"
"Columbia Blindstitch, Saddle Stitch, and Tie Clos-
ing Machine s"
N o. 15 00, " Al te rat ion Dep artment Machines "
®
HERE ARE HELPFUL
BULLETINS and CATALOGS
TO HELP YOU SOLVE
SEWING PROBLEMS
From the library of: Superior Sewing Machine & Supply LLC

BOOST PRODUCTION
WITH THESE
WORK AIDS FROM
UNION SPECIAL
u
FIHEST OUALITY MA cHINE
®
PNEUMATIC CHAIN - CUTTER -fo r use on
conventional Class 39500 and 39600 is a durab le
scissor-actio n mechanism that makes a clean
positive cui. Style 2899 A-1
~·
u
\ '
..___
AIR FAB RIC UNCURLE R-This unit, de-
signed for Cla ss 39500 machines, use s air jets
to
remove cur ls from to p and bottom plies ol flat
knit materials as fabric passes thr ough sewi ng
ar ea. Style 2899 B- 1
KNIFE GRINDER sharpens straight or angle
type kn ives, is simple and easy to opera te, elimi-
nates defective garments caused by dull knives.
PNEUMATIC FOOT LIFTER -The a ir-
operated foot lif t er for use on Class 39500
machines allows the operator to raise t he foot
simply by kne e-touchi ng an actuating switch.
CHAIN CUTTER - The above photo shows the
small pneumatic cha in cutter that is available
for installation as an accessory unit on Class
36200 Flat seamers. Style 2899A-6
.-
: ~
HEAT DISPELLER -Union Special's auxiliary
unit (a rrow) is an effective means f or reducing
oil tempe r ature where heavy duty service re·
quire s it. Style 2899 E -1
AMCO ELECTRON IC NE E DLE POSJTJONERS elimi nate the necess i ty of reaching f or the hand·
wheel to move the needle up or d own ... this all ows t he operator to keep both hands on the work,
insuring be tter control, u ni fo rm qu ality and increased production.
From the library of: Superior Sewing Machine & Supply LLC

WORLD'S FINEST QUALITY
*
INDUSTRIAL SEWING MACHINES
~'
I~
UNION SPECIAL maintains sales and service
facilities
throughout the world. These offices will
aid you in the selection of the right sewing
equipment for your particular operation. Union
Special representatives and service men are fac-
tory trained and are able to serve your needs
promptly and efficiently. Whatever your loca-
tion,
there is a Union Special Representative to
serve you . C~eck with him today.
ATLANTA, GA.
BOSTON, MASS.
CHICAGO, ILL.
DALLAS, TEXAS
LOS ANGELES, CAL.
NEW YORK, N. Y.
PHILADELPHIA, PA.
MONTREAL, CANADA
TORONTO, CANADA
BRUSSELS, BELGIUM
LEICESTER, ENGLAND
LONDON, ENGLAND
PARIS, FRANCE
STUTTGART, GERMANY
Representatives and distributors in all important
industrial c it ies throughout the world .
MACHINE COMPANY
400 N. FRANKLIN ST., CHICAGO, ILL. 60610 '
From the library of: Superior Sewing Machine & Supply LLC