UnionSpecial 39500AD User manual

F INE ST QUALITY
STYLE
39 SOOAD
CATALOG
No.
103AD
®
INDUSTRIAL
SEWING
LEWIS • COLUMBIA
MACHINES
CLASS 39500
STREAMLINED -
HIGH
SPEED OVERSEAMERS
CHICAGO
From the library of: Superior Sewing Machine & Supply LLC

Catalog No. 103 AD
(Supplement to Catalog No. 103 U)
INSTRUCTIONS
FOR
ADJUSTING AND OPERATING
LIST OF PA R TS
CLASS 39500
Style
39500 AD
The parts listed in this catalo g
furnished at li s t pric es
for repairs o n ly.
Fi rst E dition
Copyri g ht 1960
by
Union Specia l Mach i ne Co.
Rig ht s Res er ved in All Countries
MA CHINE CO M PAN Y
INDUSTRIAL SEWING MACHINES
CHICAGO
Pr i nted in U.S.A.
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IDENTIFICATION OF MACHINE
Each Union Special machine is identified by a Style number which is stamped into the
name plate.
Machines similar in construction are grouped by a Class number, which contains no
letters. Example: "39500". Letters suffixed to a Class number indicates the standard
Style of a machine. Example: "39500 AD". Letter "Z" is reserved as a suffix to the
standard Style identification to specify machine is of "Special" construction.
APPLICATION OF CATALOG
This catalog is a supplement to Catalog No. 103 U and should be used in conjunction.
Parts illustrated in this catalog represent parts not used in 39500 S, T, or U machines.
For clarity, certain 39500 S, T, and U parts are shown in phantom to help locate 39500 AD
parts.
Opposite the illustration page, parts are identified by detail number, part number,
description, and amount required.
Adjusting and operating instructions included represent only areas concerned with
39500 AD.
This catalog applies specifically to the standard Style of machine as listed herein and
can also be app li ed with discretion, to some Special machines ofClass 39500. References
to direction, suchas right, left, front, back, etc., are taken from the operator's position
while seated at the machine. Operating direction of handwheel is away from operator.
STYLE OF MACillNE
Two Needle, Two Looper, Four Thread, Overseaming Machine. Intermittent Differential
Feed, Trimming Mechanism with Spring Pressed Lower Knife, Automatic Lubricating
System.
39500 AD For seaming and intermittently gatherin g operations on pajamas, bathing suits,
house dresses, children's wear, ladies' undergarments and similar articles. Kne e
press controlled intermittent differential feed and independent swing-out auxiliary
pressure plate attachment. Three thread overedge and reinforcing stitch - seam
specification 512-SSa-1. Standard width of seam from left needle 17/64 inch. Gatherin g
ratio up to 3 to 1 depending on stitch length. Stitch range 8 to 20 per inch, standard
setting 14 per inch.
OILING
CAUTION! Oil was drained from machine when shipped, so reservoir must be fi ll ed
before beginning to operate. Oil capacity of Class 395go is six ounces. A stra i ght mi ne r al
oil of a Jaybolt viscosity of 200 to 250 seconds at 100 Fahrenheit should be used.
Machine is filled with oil at spring cap in top cover. Oil level is checked at s ig ht g au ge
on front of machine. Red bulb on oil level indicator should show between gau ge l in es .
Machine is automatically lubricated. No oilin g is necessary, other than kee p ing ma in
reservoir filled. Check oil daily before the morning start. Add oil as requir e d.
Drain plug screw is located at back of machine near bottom edge of ba se. It is a
magnetic screw designed to accumulate possible forei gn materials which may hav e e nt ere d
the crank case. It should be removed and cleaned periodically.
NEEDLES
Each Union Special needle has both type a nd si ze number. The type numb er de not es
the kind ofshank, point, length, groove, finishandotherd e tails. Thesizenumb er , s ta mp ed
on the needle shank, denotes largest diameter of blad e, measured in thousandth s of an in ch,
midway betweenshankand eye. Collectively, typ e and size numberrepresenttheco mp le te
symbol which is given on the label of all need le s packaged and sold by Union Sp ecia l.
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NEEDLES (Continued)
Style 39500 AD uses curved blade needles. The standard needle for this
style is Type 154GAS. It is a curved blade, standard length, single groove,
shallow spot, long tapered point, struck groove, chromium plated in sizes
022, 025, 027, 029, 032, 036, 040, 044.
To have needle orders promptly and accurately filled, an empty packag e,
a
sample needle, or the type and size number should be forwarded. Use de -
scription on label. A complete order would read: "1 000 Needles, Type 154GAS,
Size 036".
Selection of proper needle size is determined by size of thread used.
Thread should pass freely through needle eye {n order to produce a good stit ch
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 work-
manship for more than three-quarters of a century.
CHANGING NEEDLES
Release pressure on presser foot by turning presser foot release bushing
(S, Fig. 1) and swing presser arm (H) out of position. Turn handwheel in oper-
ating 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 their high position;
withdraw needles.
To replace needles, leave needle holder at high position and, with the flats
to the left, insert needles in holder, one on each side of spacer washer, 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 {H) to position; re-lock presser foot release bushing (S).
THREAD STAND
After threads come from cones on thread stand (Z. Fig. 1). they are brought
up through back eyelets. then down through front eyelets (Y) and through the
adjustable thread guide. Next. they are threaded through each pair of holes in
tension thread guide wire (A). down through right hand hole and up through left
hand hole. Then thread continues between tension discs (U), through slot {T).
and on through thread guide (B).
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 needles third.
Before beginning to thread , swing cloth plate open. turn handwheel in oper-
ating direction until needles (L) are at high position. release pressure on presser
foot by turning presser foot release bushing {S); and swing presser arm (H) out
of position.
Be sure threads, as they come from the tension thread guide, are between
tension discs (U) and in diagonal slots (T) in tension posts (V).
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t3 T ens i on Nut
riTension Sprin g
mTension Post
~~~Tension Dis cs
DT
ension Post
Slot
liJ Thread Guide
rilupper Looper Thre ad Eyelet
m Aux il ia ry Looper Thread Eyel et
II Lower L o oper Thread Eyelet
~~Fabric Guard Br ack et
~~~Presser A rm
Figure 1
Ne e dl e Thre ad Eyel et
Top Cove r
:\e edl e Th r ea d Ey el et
Upp er Loop er
Thread Tu be As sembl y
Lo
wer Looper
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TO THRE D LOWER LOOPER
Double end of thread and lead it through both eyes of lower looper thread
eyelet (E, Fig. 1) from right to le ft. Note: thread must pass in front of loop e r
thread pull-off (R). Lead thread behind fabric guard (F) and through fram e
looper thread g uide (G). Turn hand wheel in operating direction until heel of
lower looper (J) 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
Turn handwheel until point of upper looper (K) is all the way left. Lead
thread through auxiliary looper thread eyelet (D) from back to front, then
throu gh both eyes of upper looper thread eyelet (C) from left to right. Note:
thread must pass in front of looper thread pull-off (R). After pulling up upper
looper thread tube assembly (M), lead thread under neck of top cover casting
and down through thread tube assembly (M). Pull thread out bottom of tube;
push tube down, then insert thread throu gh upper looper eye from front to ba c k.
CAUTION! Be sure upper looper thread is under lower looper thread when
passing from tube assembly to upper looper eye.
TO THREAD THE NEEDLE
Turn handwheel in operating direction until needles (L, F i g. 1) are at their
highest pos i tion. Insert both needle threads from right to left, through both
eyes of needle thread eyelet (P), under neck of top cover casting; then down
through hole in top cover needle thread eyelet (N). Thread needles from front.
THREAD TENSIO N
The amount of tension on needle and looper threads is regulated by four
knurled tension nuts (X, Fig. 1). Tension on threads should be only e nough
to secure proper stitch formation.
PRESSER FOOT PRESSURE
Sufficient pressure to feed work un i formly should
be maintained. Should it be necessary to increase or
de crease amount of pressure on presser foot, loosen
lo ck nut (A, F ig. 2) and turn adjusting screw (B).
Adju s tin g screw has a ri g ht hand thread; so tightening
incre a ses pre ss ure, loosening decreases pressure.
Wh en pressu re a djustin g screw (B) has been properly
set, ti g hten lock nut (A). With presser foot resting
on throat plate, position locking nut (C) so that its
under surface is approximately 1I 32 inch to 1I 16 inch
from the top surface of adjusting screw (B). Set cap
(D) ag a inst locking nut (C).
FEED ECCENTRICS
Fig. 2
Feed eccentrics used in th is m a chine have been sel e cted to prod u ce a pprox-
imately 10 stitches per in ch. It will be not ed that the pa r t numb e rs of f eed
e ccentrics are No. 39540-10 for the di f fer e ntial feed and N o. 39 54 0-12 for the
main feed. Minor numb er s of t he part symbols indicate approximately the
number of stitches when us ing that eccentric. Unless otherwise specified,
machine will be shipped with above combination of eccentr i cs.
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FEED ECCENTRICS (Continued)
Following st itch number feed eccentrics are available under No. 39540- 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 one e ccentric is supplied with each machine. Additional eccen-
trics may be ordered separately. To order an eccentric, use No. 39540 with
a minor numb er suffixed to indicate number of stitches desired. Example:
"39540-12".
ASSEMBLING AND ADJUSTING SEWING PARTS
Before assembling sewing parts, remove cl oth plate, fabric guard, chip
g uard, upper knife assembly, lower knife holder assembly; then follow this
suggested sequence:
SETTING THE NEEDLE
With the throat plate in position, needles should center
in the front end of needle slots. When needles are at high
p o s it ion, needle points
should be set 15I32 inch
above throat plate (Fig. 3).
Move needle driving a rm
(A, Fig. 3), by loosening
clamp screw (B). Remove
the throat plate.
If needle thread cam
pull-off(A, Fig. 4) overlaps
looper thread pull-off (B),
separate by movin g looper
thread pull-off to back.
When re-tightening looper
~::::..1. ... .- ~--- ~ pull-off screw, be sure to
take up end play in needle
driving arm. Fig. 3
Fig. 5
At this point, in-
sert lower looper (A,
Fig. 6) into ba r (B).
With the lower loop er
at the left end of its
stroke, set po i nt 1I16
inch from cen te r of
left needle (F ig . 6),
usin g loop er ga u ge
No. 21225- 1 116.
Fig. 4
Fi g . 6
SETTING THE REAR NEEDLE GUARD
Set rear needl e gua rd (A, Fig . 5) as hi gh as p os-
Sl ble, w it hout inte r fe r ing with e ither lower loop er or
movement of lower kn if e ho l der, but still in position
to deflect needle s forw a rd . 002-. 004 inch. Scr ew
(B) is used to set r e ar need l e g uard. Make s ur e
there is no inter f erenc e be tw ee n re ar needl e gua rd
and lower looper.
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SETTING THE LOWER LOOPER
Now, finish lower looper adjustm ent . As lo wer looper
moves to the right, its point should be s et int o the s c arf
of the left needle (A, Fig. 7) until th e n ee dl es s prin g for-
ward 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 needles off back guard, set front needle
guard as closely as possible to needles without touching.
Use screw (D) to adjust and set front needle g uard. After
setting, make sure there is no interference between needle
guards and differential feed dog.
Fi g . 7
SETTING THE UPPER LOOPER
Fi g. 8
Fig. 9
Insert upper looper (A, Fig. 8) in its holder. Screw
(B) 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) on clamp holds the upper looper holder
in the shaft. Locate upper looper in its holder so that the
shank extends 1I16 to 3I32 inch beyond holder.
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 (Flg. 8).
By adjusting looper holder in or
out of upper looper shaft and by turning
the looper around its shank, set upper
looper point to cross lower looper to
the left of the lower looper eye with
0. 002 to 0. 004 clearance (Fig. 9) .
Next, turn the handwheel until up-
per looper is at the left end of its
travel. Check dimensions of upper
looper point with respect to the right
needle and throat plate (Fig. 10). If
resetting is necessary, do it by moving
the upper looper holder (A, Fig. 10).
Figure 10 represents the dimensional
setting.
Fig. 10
Dimension 17 I32 inch is increased by turning upper looper holder counter-
clockwise looking from left end of machine. Dimension 1I8 inch is increased
by pulling upper looper holder left, out of the upper looper shaft. After these
changes are made, it may be necessary to turn the upper looper a round its
shank slightly to maintain the condition shown in Fig. 9.
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SETTING THE UPPER LOOPER (C ontinued)
When the corr ec t settin g is o btained, it c an be checked
quickly as follows: As upp er lo op er is moving to the right,
when upper looper eye ce nt e rs on th e n ee dl e, the eyes of
the upper looper and n ee dl e s ho uld a lign e xa c tly (Fig. 11).
Ch ec k sett in g to avoid interference between upper looper
a nd n ee dl e on n ee dle downstroke. If needle rubs the back
of upp er l oo pe r, pull looper out of its holder slightly and
rotat e l oo per a short distance counter- clockwise, looking
from left e nd of machine. Reset to maintain dimensions
of Fi g. 9, 10, 11.
Fig. 11
SETTING THE FEED DOGS
Assemble the main and
differential feed do gs (A, B,
Fig. 12). Main and differential
feed dog3 should be leveled
with respect to the throat plate
by rotating feed tilting adjust-
ing pin (C). This pin raises or
lowers the back end of the feed
bar.
The feed dogs should be set
level at the time the teeth first
appear above the throat plate.
Fig. 12
Screw (D) locks feed tilting
adjusting pin in place. With the
feed dogs at their highest point of travel, the top of the teeth on the main and
differential feed do gs (A, B) should be 3/64 inch above the throat plate. The
c hainin g feed do g is made as on inte g ral part of the main feed dog.
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 sprin g 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 (B) and locking nut (C) against sup-
port 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.
SETTING THE UPPER KNIFE
Replace upper knife assembly. Clamp upper
knife (D, Fig. 13) in position, setting nut (E) to hold
Fig. 13
clamp (F) in its most clockwise position against upper knife. Upper knife chain
guard (J) should be positioned so that the guarding section is approximately 1/64
inch behind the cutting edge and in contact with the tops urface of the upper knife.
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SETTING THE UPPER KNIFE (Continued)
At the bottom of its stroke. front cutting edge of upper knife should extend
not less than 1/64 inch below cutting edge of lower knife.
After upperknife has been set for proper width of trim
3
screw(G) must be
tightened to lock the upper knife holding block (H) in place. This will simplif y
resetting when upper knife is replaced.
SETTING THE DIFFERENTIAL RATIO
Differential
3
plain
3
or reverse differ-
ential feed action is obtainable thru use of
the micrometer adjusting screw (Fig. 14).
The position of the differential control
lever(A) is governed bytwo settings--the
top stop (B) and the lower stop screw (C).
Amount of movement by lever between (B)
and {C) determines feed action.
Rotation of adjusting thumbscrew
(located near tension post assembly)
clockwise (moving top stop down) in-
creases differential action. A counter-
clockwise turn acts the reverse.
The micrometer adjusting screw for
Fig. 14
the top stop is ideal for continuous shirring operations where various sizes
are encountered.
For intermittent operations
3
it may be advantageous to reverse the stops--
sothe adjusting screw stop(B) isforlower stop. and the stationary stop (C) is
for upper position.
The 3 to 1 ratio machines are equipped with a stop screw {D) to prevent
differential feed dogs from striking the throat plate when a machine is set at
maximum differential
3
and screw should not be removed.
STARTING TO OPERATE
Be sure machine is threaded according to threading diagram (Fig. 1.
Pa ge 5). With thread tensions light. set looper thread eyelets (C and E) 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 down stroke. At top of needle stroke,
thread should be just tight enough to feed cha in off stitch tongue. 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 (P, Fig. 1) so that needle
cam pull-off (Q) just contacts needle thread.
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