UnionSpecial 39500AC-060 Instruction sheet

F INES T QUALITY
S TYLE
395 00A C-
060
CATALOG
No.
103AC
®
INDUSTRIAL
SEWING
LEWIS • COLUMBIA
MACHINES
TY SEWING SUPPLy CO.
UNI 824 E. 8th St.
Lo a ,Angeles, CA 9002 1' .
CLASS 39 500 f:J- (_
STREAMLINED
HIGH SPEED OVERSEAMERS
MACHINE COMPANY
C H'l C A G 0
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Catalog No. 103 AC
(Supplement to Catalog No. 103 S)
INSTRUCTIONS
FOR
ADJUSTING A N D OPE R ATING
LIST O F PA R TS
CLASS 39500
Style
39500 AC-060
The parts l i sted in this catalog are
furnish e d at list prices for repairs only.
F i rst Edit i on
Copyright 1961
by
Union Special Machine Co.
R ights R eserved in All Countries
MACHINE COMPANY
INDUSTRIAL SEWING MACHINES
CHICAGO
Pri n ted in U.S.A.
2
February. 1967
J
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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 AC-060''. 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 Sand should be used in conjunction.
Parts illustrated in this catalog represent parts not used in 39500 A, B, P or AF
machines. For clarity, certain 39500 A, B, P and AF parts are shown in phantom
to help locate 39500 AC-060 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 AC-060.
This catalog applies specifically to the standard Styles of machine as listed herein
and can also be applied with discretion, to some Special machines of Class 39500.
References to direction, such as 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 MACHINE
Two Needle, One Looper, One Spreader, Three Thread, Low Throw Overseaming
Machine. Differential Feed, Trimming Mechanism With Spring Pressed Lower Knife,
Automatic Lubricating System, • 060 Inch Needle Spacing.
39500 AC-060 For closing men's, women's and children's half hose. Seam
specification, Special SSa-1; standard seam width approximately 1/8 i nch.
Stitch range 20 to 100 per inch; standard setting 45 per inch . 3/16 inch sewing
capacity.
OILING
CAUTION! Oil was drained from machine when shipped, so reservoir must be
filled before beginning to operate. Oil capacity of Class 39500 is sia ounce s . 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 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.
Machine is automatically lubricated. No oiling is necessary, other than keepin g
main reservoir filled. Check oil daily before the morning start. Add oil as required.
Drain plug screw is located at back of machine near bottom ed ge of base. It is a
magnetic screw designed to accumulate possible foreign materials which may ha ve
entered the crank case. It should be removed and cleaned per i odically.
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NEEDLES
Each Union Sp ec ial 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
1
stamped on the needle shank~ denotes largest diameter of blade
1
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.
39500 AC-060 uses a curved blade needle. The standard needle for this style is
Type 154 GDS. It is a slabbed shank, round point, • 060 inch double slab, standard
length
1
curved blade. double groove. struck groove~ spotted~ chromium plated
needle in size 029.
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: "1000 Needles. Type 154 GDS, Size 029
11
•
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
(P, Fig. 1). and swing presser arm (D) out of position. Turn handwheel in the
operating direction until needles are attheir lowest point oftravel. Using hexagonal
socket wrench No. 21388 AU, furnished with machine. loosen needle clamp nut about
1/4 turn. Againturnhandwheel until needles are athighposition. Withdraw needles.
To replace needles, leave needle holder at high position and, with the flats to the
left, insert needles in holder until they rest against the 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 (D) to position; re-lock presser foot bushing (P).
THREAD STAND
After thread comes from thread cones (positioned on cone support (X)), it is
brought up through BACK thread eyelet, then down through FRONT thread eyelet
(R. Fig. 1). Next, thread is extended down through the right hand hole and up through
left hand hole ofthe tension thread guide wire (A). Thread is then continued between
tension discs (W), through slot (V)
1
and on through thread guide (B).
THREADING
Only parts involved in threading are shown in threading diagram (Fig. 1). Parts
are presented in their relative positions for clarity.
The following recommended procedure simplifies threading: Beginning with
complete threadin g of lower looper~ progress to complete threading of right needle~
and conclude by complete threading for left needle. Steps for threading are given
on following pages.
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I
NOTE: For left needle
thread only, invert
tension discs (W) and
add
(2) pads (39592 E)
between them. Thread
goes between the pads.
Tension
Guide
~
~read
Lower Looper
~Thread Eyelet
~resser
Fabric
~Guide
1!1 Bracket
Figure 1
5
IU
Needles-IJ Upper Spreader
Low~r {
La~
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THREADING (Continued)
Priortothreading. swing cloth plate open, turn handwheel in operating direction
to bring needles (J) into high position. Release pressure on presser foot by a
counterclockwise turn of the release bushing (P). and then swing presser arm (D)
out of position.
CAUTION! Make sure the threads, as they extend from the tension thread guide
wire (A, Fig. 1). are between tension discs (W) and in diagonal slots (V) of the
tension posts ( U).
TO THREAD LOWER LOOPER
Double end of thread and lead it through both eyes of lower looper thread eyelet
(C) from right to left. Note: thread must pass in front of looper thread pull-off (N).
Lead thread through eyelet on top of fabric guard (E) and through eye of frame thread
guide (F). Turnhandwheelin operating direction untilheel oflower looper (G) is all
the way to the left; then, thread through both eyes from left to right. Right eye of
lower looper can be threaded easily if tweezers are in left hand.
TO THREAD NEEDLES
Turn handwheel in operating direction until needles (J) are at their highest
position. Insert both needle threads from right to left, through BOTH eyes of needle
thread eyelet (L). under neck of top cover casting and then down through holes in top
cover needle thread eyelet (K). 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 eyelet. Thread needles from the front.
THREAD TENSION
The amount of tension on the needle and looper threads is regulated by three
knurled tension nuts (S, Fig. 1). Tension on threads should be only sufficient to
secure proper stitch formation.
PRESSER FOOT PRESSURE
Sufficient pressure to feed the work uniformly
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;
tightening will increase pressure, loosening decreases
the pressure. When pressure adjusting screw (B) has
been properly set. tighten the lock nut (A). With
presser foot resting on throat plate. position locking
nut (C) sothatits under surface is approximately 1/32 ~
inch to 1/16 inch from the top surface of the adjusting ~
screw (B). Set cap (D) against locking nut (C). f\J Fig. 2
FEED ECCENTRICS
On the 39500 AC-060 machine, eccentrics have been selected to produce
approximately 35 stitches per inch. It will be noted on the 39500 AC-060 machine
that the part number of the main feed eccentric is No. 39 540-60 • while that of the
differential feed eccentric is No. 39540-30 • Minor numbers of the part symbol
indicate approximately the number of stitches obtainable when using that eccentric.
Unless otherwise specified, the 39500 AC-060 machine will be shipped with the
39 540-60 main feed eccentric and 39 540-30 differential feed eccentric.
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FEED ECCENTRICS (Continued)
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- 4, 5, 6,
7. a. 9, 10. 11. 12. 13. 14, 15. 16. 18. 20. 22. 24. 26. 2a. 3o. 32. 34. 36, 4o. 5o.
60, 70, 100. Only two eccentrics are supplied with each machine. Additional
eccentrics may be ordered separately. To order. use No. 39540 with a minor
number suffixed to indicate number of stitches desired. Example: 39540-70.
ASSEMBLING AND ADJUSTING SEWING PARTS
Before assembling sewingparts. remove clothplate. fabric
guard, chip guard. upper knife assembly. lower knife assembly.
Then. follow this suggested sequence.
SETTING THE NEEDLE
Fig. 3
With throat plate in position. needles should center in the
front end of needle slot. When needles are / at high position. the
needle points should be set 1/2 inchabovethroat plate (Fig. 3).
Atthis point, insert lower looper (A, Fig. 4) into bar (C). With
lower looper at the left end of its stroke. set the looper point 1/8 inch
from center ofleft needle, using looper gauge No. 21225 G-1/8. Do
not have lower looper deflecting the needles. Tighten nut (B).
SETTING THE REAR NEEDLE GUARD
Set rear needle guard as high as possible (A. Fig. 5) without
interfering with either lower looper or movement of lower knife
holder. but still in position to deflect needle forward • 002 to • 004
inch. Screw (B) is used to set the rear needle guard. Make sure
there is no interference between the rear needle guard and lower
looper.
SETTING THE LOWER LOOPER
Fig. 4
Now, finish lower looper adjustment. As looper moves
to the right. its point should be set into the needle scarfs
Fig. 5
(A. Fig. 6) until needles spring for-
ward from rear guard surface another
. 002 to • 004 inch.
SETTING THE FRONT
NEEDLE GUARD
Assemble front needle guard (C,
Fig. 5). When lower looper is spring-
ing needle off back guard, set the front
needle guard as close as possible to
needles without touching. Screw (D) is
used to adjust and set front needle
guard. After this setting. make sure
there is no interference between the
needle guards and differential feed dog.
7
Fig. 6
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SETTING THE UPPER SPREADER
Ins e rt upp er spreader (A, Fig. 7) in its holder. Screw (B)
holds upp er spr e ad er in its holder and permits it to be pushed in
or out orturn ed around its shank. Insert upper spreader holder
i nto spr e ad er shaft (if not already in place). Screw (C) on the
clamp holds the upper spreader hold er in the shaft. Locate upper
spreaderinitsholder sothat the shank ext e nds 1/32 to 1/16 inch
beyond holder (Fig. 7).
When the upper spreader is at the right end of its stroke,
upper spreader hold er should be set to position upper spreader
shank back of vertical.
Fig. 7
Next, turn the handwheel until upper spreader is at the left end
of its travel. Check dimensions of the lower point of the spreader
with respect to needle and throat plate (Fig. 8) and the following
dimensions; distance from centerline of left needle to point of
spreader should be approximately 9/64 inch, and the distance from
throat plate to point of spreader should be approximately 15/32 inch.
Check setting to avoid interference betwee n upper spreader and
needles on needle down stroke. If needles rub the back of upper
spreader, pull spreader out of its holder slightly and rotate holder
a short distance counterclockw i se, looking from left end of machine.
Fig. 8 Reset to maintain di mensions suggested above and in Fi g. 8.
SETTING THE FEED DOGS
Assemble and set the differe n-
ti
al feed dog (A, Fig. 9) and ma in
feed dog (B) so that top surfaces of
the feeding surfaces all lay in the
same plane. This can be checked
by sighting across feeding surface
with a straight edge. Feed surfaces
should now be leveled with the
throat plate surfaces by rotating
feed tilting adjusting pin (D). This
pin raises or lowers the back end
of both feed bars at the same time.
Fig. 9
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 about 3/64 inch above throat plate.
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 lower knife holder assembly. Lower knif e
(A, Fig. 10) should be set with cutting edge flush with throa t
plate surface. Adjustments are made with hexagonal head
screw wh i ch holds lower knife. Lower knife is spring
pressed against upper knife, so no lateral adjustment is
necessary when width of trim is changed.
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SETTING THE LOWER KNIFE (Continued)
Lower knife may be secured in any position by tightening screw (B) and locking
nut (C) against support bracket. Because screw (B) also serves as latch pin for th e
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. 10) 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 notless than
1/64 inch below cutting edge oflower knife. The chain guard (J) 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 (G) should be
tightened to lock upper knife h6lding block (H) in place. This will simplify resetting
when upper knife is replaced.
Fig. 11
SETTING THE STITCH LENGTH
Length of stitch is determined by the combination of
feed eccentrics used. Outer (left) eccentric (A, Fig. 11)
actuates main (rear) feed dog, while the inner (right)
eccentric (B) actuates the differential (front) feed dog.
In assembling feed eccentrics, be sure hubs are facing
each other. Be careful not to damage shaft or key. Tighten
nut (C) securely. Be sure wool yarn in oil tube (F) touches
feed eccentric connections.
To change feed eccentrics, remove nut (C) from end of
shaft (D). Turn hand wheel in operating direction until key
slot in eccentric is toward front. Using hooked eccentric
extractor (E), supplied with machine, reach behind
eccentrics as shown and withdraw eccentrics. It may be
necessary to move hand wheel back and forth slightly during
extraction.
If eccentrics are unusually tight fitting, in addition to removing nut (C, Fig. 12)
from shaft (D), it may be helpful to remove nut (G) and feed driving connection (H).
Then, continue as originally suggested.
SETTING THE PRESSER FOOT
Assemble presser foot to presser arm.
With needle in high position, swing presser
arm into sewing position and lock in place.
If necessary, presser foot can be realigned
with throat plate slots by shifting foot lifter
lever shaft.
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Fig. 12
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SETTING THE PHESSER FOOT (Continued)
Foot lifter lever arm (A. Fig. 13) and collar (B) secure the shaft. Be sure
presser arm does not bind and rise when presser foot release bushing is unlocked.
To center presser foot and stitch tongue with respect to throat plate needle hole,
loosen presser foot hinge screw.
Adjust lifter lever stop screw (C) so that
presser foot can be raised no higher than upper
spreader will permit; then, lock nut (D). To find
this maximum safe position, turn the hand wheel
so point of upper spreader is directly over
presser foot tongue. H.aise presser foot by
depressing the presser foot treadle and man-
ually lower the toe of foot. Height adjustment is
correct if presser foot tongue does not contact
the upper spreader. There should be from 1/16
to 1/8 inch free motion of foot lifter lever before
presser foot begins to rise. This adjustment
is made with screw (E). locked with nut (F).
Fig. 13
Finally, re-assemble chip guard, fabric guard, cloth plate.
STARTING TO OPERATE
Be sure machine is threaded according to diagram for your style of machine
(Fig. 1). With thread tensions light, set looper thread eyelet (C, Fig. 1) about
horizontal and back in its front to back location. Operate machine slowly, without
presser foot in place, to make sure that chain forms and moves offthe 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 threads are drawn from cones on needle down stroke. Attop of stroke, thread
should be just tight enough to feed chain off throat plate stitch tongue. With needle
at bottom of stroke, position needle thread eyelet (L, Fig. 1) so that needle thread
cam pull-off (M) just contacts needle thread. The eyelet (L) is adjusted correctly
in its frontto back position when the desired stitch is obtained with the least amount
of needle thread tension when sewing over the complete speed range.
LOWER LOOPER THREAD CONTROL
During needle down stroke, forward stroke of looper thread pull-off (N, Fig. 1)
will draw lower looper thread through the tension. When normal amount of looper
thread is drawn, lower looper thread will have almost all slack taken up as looper
thread pull-off reaches its most rearward position.
If lower looper thread has a loose appearance in the seam, move looper thread
pull-off eyelet (C, Fig. 1) forward and raise slightly. If, however, the eyelet 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 tens i on applied.
CAUTION! Do not try to obtain a tight looper thread appearance on the seam by
carrying high tensions.
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