UnionSpecial 39500FW Instruction sheet

F INEST QUA LIT Y
STY LE
3950 0F W
CATALOG
No.
103FW
. I
I
Ztnum~ ®
INDUSTRIAL
SEWING
LEWIS • COLUMBIA
MACHINES
CLASS 39500
HI-STYLED HIGH SPEED
TWO NEEDLE FOUR THREAD
DIFFERENTIAL FEED
OVERSEAMING MACHINE
CHICAGO
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Catalog No. 103 FW
{Supplement to Catalog No. 103 FA)
INSTRUCTIONS
FOR
ADJUSTING AND OPERATING
LIST OF PARTS
CLASS 39500
Styl e
39500 FW
F i rst Ed i t i o n
Copyri g ht 1967
By
Union Spec i al M a chine Co.
Ri g hts R e s e rv e d in All Count ries
MACHINE COMPANY
INDUSTRIAl SEWING MACHIN ES
CHICAGO
P r i n t e d i n U .S. A .
2
Ju ne , 1970
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IDENTIFICATION OF MACHINES
Ea ch Union Special machine is identif i ed by a Style number on a name plate on
the machin e. St yl e numbers are classified as standard and special. St andard Styl e
numbers hav e on e or more letters suffixed, but never contain the letter "Z".
Example: "Style 39500 FW". Special Style numbers contain the letter "Z". When
only mino r changes are made in a standard machine, a "z" is suf fi xed to the stan-
dard Style number. Example: "Style 39500 FWZ".
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
11
•
APPLICATION OF CATALOG
This catalog is a supplement to Catalog No. 103 FA and should be used in con-
junct i on therewith. Only those parts used on Style 39500 FW, but not on Style 39500
FP 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 illustration. Re-
ference numbers should never be used in ordering parts. Always use the part num-
ber 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.
STYLE OF MACHINE
Hi-Styled High Speed, Two Curved Blade Needles, Two Loopers, Four Thread
Overseaming Machine. Differential Feed, Trimming Mechanism with Spring
Pressed Lower Knife, Automatic Lubricating System.
39500 FW Medium to heavy duty machine for seaming medium to heavy weight
knitted and woven fabrics with a modified safety stitch. For operations on pa-
jamas, bathing suits, house dresses, children's wear, ladies' undergarments
and similar garments of light to medium heavy weight woven and knitted g ar-
ments of wool, cotton, silk and synthetics. Seam specification 512-SS a -1.
Standard width of seam from left needle 17/64 inch. St i tch range 6-20 per inch.
Cam adjusted main and differential feeds. Maximum recommended speed 6500
R. P.M.
OILING
CAUTION! Oil was dr a ined from machine wh en shipped, so reservoir must be
filled before beginning to operate. O il capacity of Class 39500 is s~ ounces. A
straight mineral oil of a Saybolt viscosity of 90 to 125 seconds at 100 Fah re nh e it
should be used.
Machine is fill ed with oil at sprin g cap in top cover. Oil le vel is ch e ck ed at
sight g auge on front of machine. Red tip of oil indicator should show b et w ee n
gau ge lines when machin e is station a ry.
3
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OILING (Continued)
Machine is automatically lubricated. No oiling is necessary. other than keepin g
main reservoir filled. Check o il daily before the morning start; add oil as requi r e d.
Th e o il dr ai n plug screw is located at back of machine near bottom edge of
base. It is a ma g net i c screw designed to accumulate possible foreign materials
wh i ch may hav e en te red the crank case. It should be removed and cleaned periodi-
cally.
NEEDLES
Each Union Sp e cial Needle has both type and size number. The type number
denotes t he kind of shank, point. length, groove. finish and other details. The siz e
number. stamp ed on the needle shank. denotes largest diameter of blade, me asur ed
in thousandths of an inch, midway between sha11k and eye. Collectively, type and
size number repr e sent the complete symbol wh i ch is given on the labe l of a ll nee -
dles packaged and sold by Union Special.
Class 39500 machines use a curved blade needle. The standard recommended
needle for the machine covered in this catalog is Type 154 GAS. Below is the des-
cription and sizes available of the recommended needle.
Type No.
154 GAS
Description and Sizes
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, 0•19, 054.
To have needle orders promptly and acc u rately 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 Ne edles, Type 154 GAS, Size 036 ".
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 s ti tch formation.
Success in the operation of Union Speci al ma chines can be secured only by use
of needles pac k aged under our brand name, ~ • which is backed by a re-
putation for producing highest quality needles in materials and workmansh ip for
more than three- quarters of a century.
CHANGING NEEDLES
Release pressure on presser foot by turnin g presser foot release bush ing (AG,
Fig. 1) and swing presser arm (U) out of position. Turn handwheel in operating di-
rection until needl e is at its lowest point of trav e l. Using hexagonal sock et wrench
No. 21388 AU, furnished with machine, loosen needle clamp nut about 1/ 4 turn.
Again turn handwheel until needle is at hi gh position; withdraw ne edl e.
To replace ne e dle, leave needle hold er at hi gh position and, with th e fl at to th e
left, insert needle in hold er until it r e sts ag ainst stop pin. Ke epin g ne e dl e in this
position, turn handwheel until holder is ag ain at its low point of trav e l; th en ti g ht en
nut. Return press er arm (U) to position; re-lock presser foot rel e ase bushi ng (AG).
4
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(D Tension Nut
(~ T e nsion Spring Fe rrul e
~
Tension Sprin g~
~ __ __ _( ~~~ ~'
~ T e nsion Po st
IIJ sprin g Shield _, ;::
O Tension Dis cs ·::: · ::--~
(3 Tension Po st Slo ~ · · ''· ..
II Tension Dis c Felt·· ..
[i Tension Thread Gu
liJ Front Thread Guide
~~~ Upper Looper Thread Eyelet
~~ Auxiliary Looper Thread Eyelet
m Lower Looper Thread Eyelet
m Fabric Guard Bracket
__ .....,
D Frame Looper
Thread Guide
m Presser Arm
Fig. 1
5
Top Cover
IUI ~ :II Needle Thread Eyelet
Upper Looper
UIIIZ..~ Thread Tube Assembly
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THREAD STAND
After thread comes from cones on cone support (A, Fig. 1), the needle threads
are threaded through the back bar of the thread eyelet (B), under the middle bar and
through the center holes of the front bar. The looper threads come from the cones,
through holes of the middle bar from back to front and then through the two outside
holes of the front bar. Next it is threaded through the upper holes of tension thread
guide (C) front to back and then through the lower holes from back to front. The
threads continue between the tension discs (J), through tension post slot (K) in ten-
sion post (G) and on through front thread guide (M).
THREADING
Only parts involved in threading are shown in the threading diagram (Fig. 1).
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 lower looper first, upper looper second, and the needles third.
Before beginning to thread, swing cloth plate open, turn handwheel in operating
direction until needles (X) are in high position, release pressure on presser 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 the 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.
TO THREAD LOWER LOOPER
Double end of thread and lead it through both eyes of lower looper thread eye-
let (R, Fig. 1) from right to left. NOTE: Thread must pass in front of looper thread
pull- off (AF). Lead thread behind fabric guard (S) and through hole of frame looper
thread guide (T). Turn handwheel in operating direction until heel of lower looper
(V) is all the way to the left; then thread through both eyes from left to right. Left
eye of lower looper can be threaded easily if tweezers are in left hand.
TO THREAD UPPER LOOPER
Turn handwheel until point of upper looper (W) is all the way left. Lead thread
through auxiliary looper thread eyelet (P) from back to front, then through both
eyes of upper looper thread eyelet (N) from left to right. NOTE: Thread must pass
in front of looper thread pull-off (AF). After pulling up upper looper thread tube
assembly (AA), lead thread under neck of top cover casting and down through thread
tube assembly (AA). Pull thread out bottom of tube; push tube down, then insert
thread through upper looper eye from front to back.
CAUTION! Be sure upper looper thread is under lower looper thread when
passing from tube assembly to upper looper eye.
TO THREAD THE NEEDLE
Turn handwheel in operating direction until needles (X, Fig. 1) are in their
highest position. Insert 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
through the right hole and the left needle thread through the left hole of the top co-
ver needle thread eyelet. Thread needles from the front.
6
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THREAD TENSION
The amount of tension on needle and looper threads is regulated by the tension
nut (D, Fig. 1). Tension on threads should be only enough to secure proper stitch
formation.
PRESSER FOOT PRESSURE
Sufficient presser foot pressure to feed work uniformly
should be maintained. Should it be necessary to i ncrease or
decrease amount of pressure on presser foot, loosen lock
nut (A~ Fig. 2) and turn adjusting screw (B). Adjusting
screw has a right hand thread so tightening increases pres-
sure, loosening decreases pressure. When pressure adjust-
ing 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 approximately 1/3 2 inch
to 1/16 inch from the top surface of adjusting screw (B).
Set cap (D) against locking nut (C).
FEED ECCENTRICS
Fig. 2
Feed eccentrics used in Style 39500 FW machines have been selected to produce
approximately 10 stitches per inch. It will be noted that the part number of main
feed eccentric is No. 39540 B-12 while that of differential feed eccentric is No.
39540 B-10. Minor numbers of the part symbol indicate approximately the number
of stitches obtainable when using that eccentric. Unless otherwise specified, rna-
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 de-
gree 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:
11
39540 B-12".
ASSEMBLING AND ADJUSTING SEWING PARTS
Before assembling and adjusting sewing parts, remove cloth plate, fabric
guard, chip guard, upper knife assembly. lower knife holder assembly. then follow
this suggested sequence:
Fig. 3
SETTING THE NEEDLE
With throat plate assembled in position, needles
should center in th e front end of needle slots. When
needles are at hi gh position, needle points should be
set 31/64 inch above throat plate (A, Fig. 3). To
align needl es or set the height above the throat plate,
move needl e dr i ving arm (B. Fig. 3) by loosening
clamp screw (C). Remove throat plate, after needle
has been set pr operly and clamp screw (C) has been
tighten.
7
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Fig. 4
Fig. 5
SETTING THE NEEDLE (Continued)
If needle thread cam pull-off (A, Fi g. 4) ov er -
laps looper thread pull- off (B), separate by movin g
looper thread pull- off back. When retightening loo -
per pull- off sc r ew, be sure to take up end play in
needle driving arm.
At this point. insert lower looper (A. Fig. 5)
into bar (B). Wi th lower looper at left end of its
stroke. set looper point 1/16 inch fr om the center of
left needle (Fig. 5), using looper gauge No. 21225-
1/16. Do not have lower looper deflecting needle.
Tighten nut (C).
Now assemble differential (front) feed dog.
SETTING THE REAR NEEDLE GUARD
Set rear needle guard (A. Fig. 6) as high as
possible. without interfering with either lower looper
or movement of lower knife holder. but still in posi-
tion to deflect needles forward . 002-. 004 inch. Screw
(B) is used to set rear needle guard. Make sure there
is no interference between rear needle guard and low-
er looper.
SETTING THE LOWER LOOPER
Now finish lower looper adjustment. As lower
looper moves to the right. its point should be set into
the scarf of the left needle (A, Fig. 7) until the needles spring
forward from rear guard surface another . 002-. 004 inch.
SETTING THE FRONT NEEDLE GUARD
Assemble front needle guard (C. Fig.
6). When lower looper is springing nee-
dles off rear needle guard. set front nee-
dle guard as close as possible to needle
without touching. Screw (D) is used to ad-
just and set front needle guard. After this
setting make sure there is no interference
between needle guards and differential
feed dog.
SETTING THE UPPER LOOPER
Insert upper looper (A. Fig. 8) in its Fig. 7
holder. Screw (B) holds upper looper in its
Fig. 6 holder, and permits it to be pushed in or out. or turn ed a-
round its shank. Insert upper looper holder into upper looper
shaft, if it is not alr e ady in place. Screw (C) on clamp holds the upp er loop er hold-
in the shaft. Locate upper looper in its holder so that the shank extends 1/16 to 3/3 2
inch beyond holder.
~~~ 8 ~ ----- J
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SETTING THE UPPER LOOPER (Continued)
When the upp er looper is at the right end of its stroke,
upper looper hold er should be set to position upper looper
shank back of vertical (F i g. 8). Be sure there is a clearance
between heel of loop er and casting.
By adjusting looper holder in or out
of upper looper shaft and by turning the
loope r around its shank, set upper loo-
per point to cross lower looper to the
left of the lower looper eye with 0. 00 2
to 0. 004 clearance (Fig. 9).
Next, turn the handwheel until upper
looper is at the left end of its travel.
Check dimensions of upper looper point Fig. 8
with respect to the right needle and
Fig. 9
throat plate (Fig. 10). If resetting is necessary, do it by
moving the upper looper holder (A, Fig. 10). Figure 10 re-
presents the correct dimensional setting.
Dimension 17/32 inch is increased by turning upper looper
holder counterclockwise looking from left end of machine. Di-
mension 9/64 inch is increased by pulling upper looper holder
to the left, out of the upper looper shaft
11
After these changes
are made, it may be necessary to turn the upper looper around
its shank slightly to maintain the condition shown in Fig. 9.
When the correct setting is obtained, it
can be checked quickly as follows: As upper
looper is moving to the right and the upper
looper eye centers on the right needle, the
eyes of the upper looper and needle should
align exactly (Fig. 11).
Fig. 10
Check setting to avoid interference between upper loo p er
and needle on needle downstroke. If needle rubs the back of up-
per looper, pull looper out of its holder slightly and rotate loo-
per a short distance counter- clockwise, looking from left end of
machine. Reset to maintain dimensions of Figs. 9, 10, 11.
Fig. 11
SETTING THE FEED DOGS
Assemble the main and differen-
tial feed dogs (A, B, Fig. 12). Main
and differential feed dogs should be
leveled with respect to the throat
plate by rotating feed tilting adjusting
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. Screw (D) locks feed
Fig. 12
tiltin g 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 dogs (A, B) should be 3/64 inch a-
bove the throat plate. The chaining feed dog is made as an integral part of the main
feed dog.
9
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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 hexa-
gonal head screw which holds lower knife. Lower knife
is spring pressed against upper knife, so no lateral ad-
justment is necessary when width of trim is changed.
Lower knife may be secured in any position by tight-
ening screw (B) and locking nut (C) against support
bracket. Because screw (B) also serves as latch pin for
the cloth plate latch spring, it should always be locked
with nut (C) even when screw is not tightened against
lower knife holder.
SETTING THE UPPER KNIFE
Replace upper knife assembly. Clamp upper knife
(D, Fig. 13) in position, setting nut (E) to hold clamp
(F) in its most clockwise position against upper knife.
Upper knife chain guard (J) should be positioned so that
the guarding section is approximately 1/64 inch behind Fig. 13
the cutting edge and in contact with the top surface of the
upper knife.
At the bottom of its stroke, front cutting edge of upper knife should extend not
less than 1/64 inch below the cutting edge of lower knife.
After upper knife has been set for the proper width of trim, screw (G) must be
tightened to lock the upper knife holding block (H) in place. This will simplify re-
setting when upper knife is replaced.
SETTING THE STITCH LENGTH
Length of stitch is determined by the combination of feed eccentrics used. Out-
er (left) eccentric (A, Fig. 14) actuates main (rear) feed dog; while the inner (right)
eccentric (B) actuates the differential (front) feed dog.
In assembling the feed eccentrics, be sure hubs
are facing each other. Be careful not to damage shaft
or key. Tighten nut (C) securely.
Fig. 14
To change feed
eccentrics, remove
nut (C) and washer
(D) from end of shaft
(E). Turn handwheel
in operating direc-
tion until key slot in
eccentric is toward
the front. Using hook-
ed eccentric extrac-
tor (F), supplied with machine, reach' behind
eccentrics as shown and withdraw eccentrics. It
may be necessary to move handwheel back and
forth slightly during extraction.
Fig. 15
If eccentrics are unusually tight fitting, in addition to removing nut (C) and
washer (D) (Fig. 15) from shaft (E), it may be helpful to remove nut (G) and feed
driving connection (H). Then continue as originally suggested.
10
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