UnionSpecial 39500N Series Instruction sheet

FINEST QUALITY
STYLES
39500N
CATALOG
No.
103R
SECOND
EDITION
LEWIS • COLUMBIA
CLASS 39500 .
S TREAMLINED
®
INDUSTRIAL
S E WING
MACHINES
HIGH SPEED OVERSEAMERS
CH I CAGO
From the library of: Superior Sewing Machine & Supply LLC

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From the library of: Superior Sewing Machine & Supply LLC

Fe br ~ a ry. 1971
Catalog No. 103 R
INSTRUCTIONS
FOR
ADJUSTING AND OPERATING
LIST OF PARTS
CLASS 39500
Style
39500 N
Second E clition
Copyright 1957
by
Union Special Machin e Co.
Rights Reserved in All Countries
MACHINE COMPANY
INDUSTRIAL SEWING MACHINES
CHICAGO
Printed in U.S.A.
3
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FOREWORD
The Class 39500 machine is Union Special' s· latest overedger. New
streamlined styling, automatic lubrication, and light running high speed
performance are characteristics of these machines. All parts are made by
precision methods insuring complete interchangeability.
It is our constant aim to furnish carefully prepared information that will
enable the customer to secure all possible advantages from the use of Union
Specials. The following pages contain valuable operating and adjusting data,
and illustrates and describe the parts for Styles in Class 39500.
Union Special representatives will be found in all manufacturing centers,
anxious to cooperate with you to plan and estimate requirements.
~ MACH/NECOMPANY
Engineering Department
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IDENTIFICATION OF MACHINE
Each Union Sp e cial carries a Style number which is stamped in the 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 N". Special Style numbers contain the
letter "Z". When only minor changes are made in a standard machine, a "Z"
is suffixed to the standard Style number. Example: "Style 39500 NZ".
Styles of machines similar in construction are grouped under a Class num-
ber, which contains no letters. Example: "Class 39500".
APPLICATION OF CATALOG
This catalog applies specifically to the standard Styles of machines as listed
herein. It can also be applied with discretion to some special machines in
Class 39500. All references to directions, such as right and left, front and
back, etc .• are taken from the operator's position while seated at the machine.
Operating direction of handwheel is away from operator.
STYLES OF MACHINES
Single Curved Blade Needle, Two Looper, Three Thread, Overseaming Ma-
chine. Plain Feed, Trimming Mechanism with Spring Pressed Lower Knife,
Automatic Lubricating System.
39500 N For seaming garment pockets and similar operations on heavyweig-ht
fabrics. Seam specification 504 SSa-1, standard seam width 3/16 to 7/32
inch; stitch range 8-20 per inch
1
standard setting 12 per inch; cam adjusted
plain feed.
OILING
CAUTION! Oil was drained from machine when shipped, so reservoir
must be filled before beginning to operate. Oil capacity of Class 39500 is six
oun8es. 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 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.
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 periodi-
cally.
NEEDLES
Each UnionSpecialneedle has both type and size number. The type number
denotes the kind of shank, point, length, groove, finish and other details. Th e
size number, stamped on the needle shank, denotes largest diameter of blade,
measured in thousandths of an inch, midway between shank and eye. Collec-
tively, type and size number represent the complete symbol which is given on
the label of all needles packaged and sold by Union Special.
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NEEDLES (Continued)
Style 39500 N uses a curved blade needle. 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, 049, 054 ..
To have needle orders promptly and accurately filled, an empty package,
a sample needle, or the type and size number should be forwarded. Use 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 in order to produce a good stitch forma-
tion.
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 hi
0
hest 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 bushin g
(U, Fig. 1) and swing presser arm (H) out of position. Turn handwheel in oper-
ating direction until needle is at its lowest point of travel. Usin g he xa g onal
socket wrench No. 21388 AU furnished with machine, loos en ne e dle clamp nut
about 1 /4 turn. Again turn handwheel until needle is at hi gh pos i tion; wi th-
draw needle.
To replace needle, leave needle holder at high posit i on and, wi th the flat
to the left, insert needle in holder until it rests aga in st stop pin. K ee pin g
needle in this position, turn handwheel until holder is again at its low po int of
travel; then tighten nut. Return press er arm (H) to positio n; r e -lock pr es s er
foot release bushing (U).
THREAD STAND
Afterthread comes from cone on thread stand (V, Fig. 1), it i s brou g ht up
through back thread eyelet, th en down throu gh fro nt thr e ad eyel et (W). Nex t it
is threaded through each pair of hole s in tens ion thread g uid e wir e (A). down
right hand hole and up throu gh l e ft hand hol e . Then thread cont i nu es be tw ee n
tension discs (AD), throu gh slot (AE), and on throu gh th rea d guide (B ).
THREADIN G
Only parts involv ed in thr e adin g are s hown in threadin g diagr am ( Fig . 1 ).
Parts are plac ed in th eir relative posit i ons for clar it y.
It will simplify thr e adin g this m a ch ine to f oll ow r e comm e nd ed se qu ence of
threadin g low er looper first, upper loo pe r se cond, and n ee dl e th ir d.
Before b egi nning to thr e ad, swin g clo th plate open, tu r n h andwh ee l in op er -
atin g direct i on until ne e dle (N) is at hi gh position, r ele a se pr ess ur e on pr esse r
foot by turn ing presser foot r e lease bu s hing (U); and s wi ng pr esser a rm (H) out
of position.
Be sure thr e ads, as th ey com e from t he ten si on thr ea d guide, are b et w ee n
tens
ion d is cs (AD) and in diagon al slot s (A E ) in ten si on po st s (AC).
(j
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.,.,., , '
llilitll Cll S I 011 1
ut
I'J:IIren ~ ion Po s t
BJT, · ns aon l' o .< t
;'; lot
Ten:<ion Thread
1!1 Thread Guioc
BUpper Looper Thread Ey e! et
~Auxiliary Looper Thread Ey ele
IJ Lower Loo p er Thr ad E yel et
IJ Fabric Guard Br ac ket
aF'rame LoopPr
CJrr,.~ ~ • ·r Arm
Fig. 1
7
Cone Suppo!'l
Pres.rr foot HP! en•e H u s hin ~
----------------
--- --
---
---
- --
--
---- ..
---
' ·
---
--- '
Thread P ull-o ff
-·<- ..
~ ' ', "t-- - -- - ----
NPPdle Th read C am ! ~11-off
..... __ .:.,. ., ...
-- -
-- -
---
Nee dle Thr e ad E yelet
Low er Loo per
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TO THREAD LOWER LOOPER
Doubl e end of thread and lead it through both eyes of lower looper thread
e yel et (E, Fi g. 1) from right to left. Note:thread must pass in front of looper
t hread pull-off (T). Lead thread behind fabric guard (F) and through both holes
of frame looper thread guide (G). Turn handwheel in operating direction until
heel of lower looper (K) 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 (L) is all the way left. Lead
thread through auxiliary looper thread eyelet (D) from back to front, then
through both eyes of upper looper thread eyelet (C) from left to right. Note;
thread must pass in front of looper thread pull-off (T). 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 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 needle (N, Fig. 1) is at its
highest position. Insert needle thread from right to left, through both eyes of
needle thread eyelet (R), under neck of top cover casting; then down through
hole in top cover needle thread eyelet (P). Thread needle from front.
THREAD TENSION
The amount of tension on needle and looper threads is regulated by three
knurled tension nuts (AA, Fig. 1). Tension on threads should be only enough
to secure proper stitch formation.
PRESSER FOOT PRESSURE
Sufficient pressure to feed 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; so tightening
increases pressure, loosening decreases pressure.
When pressure adjusting screw (B) has been properly
set, tighten lock nut (A). With presser foot resting
on throat plate, position locking nut (C) so that its
under surface is approximately 1/32 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 eccentric used in this machine has been selected to produce approx-
imately 12 stitches per inch. It will be noted that the part number of feed
eccentric is No. 39540-12. Minor number of the part symbol indicates approx-
imately the number of stitches when usin g that eccentric. Unless otherwise
specified, machine will be shipped with above eccentric.
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FEED ECCENTRICS (Continued)
Following stitch 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 eccentric is supplied with each machine. Additional eccen-
trics may be ord e red separately. To order an eccentric, use No. 39540 with
a minor number suffixed to indicate number of stitches desired. Example:
11
39540-8
11
•
ASSEMBLING AND ADJUSTING SEWING PARTS
Before assembling 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 in position, needle should center in
the front end of needle slot. When needle is at high position,
needle point should be set
1/2 inch above throat plate
(Fig. 3). Move needle
driving arm (A, Fig. 3) by
loosening clamp screw (B).
Remove throat plate.
If needle t h r e a d cam
pull-off(A,•Fig. 4) overlaps
looper thread pull-off (B),
separate by moving looper
thread pull-off back. When
retightening looper pull-off
screw, be sure to take up
· end play in needle driving
arm.
At this point, in-
sert lower looper (A,
Fig. 6) into bar (B).
With lower looper at
left end of its stroke,
set looper point 1/8
inch from center of
needle (Fig. 6), using
looper gauge No.
21225-1/8. Do not
have lower looper de-
flecting needle.
Tighten nut.
Fig. 4
Fig. 6
Now assemble the main feed dog.
SETTING THE REAR NEEDLE GUARD
Set rear needle guard (A, Fig. 5) as high as pos-
sible, without interfering with either lower looper or
Fig. 5 movement of lower knife holder, but still in position
to deflect needle forward -. 002 - . 004 inch. Screw (B)
is used to set rear needle guard. Make sure th e re is no interference between
rear needle guard and lower looper.
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SETTING THE LOWER LOOPER
Now finish lower looper adjustment. As lower looper
moves to the right, its point should be set into the needle
scarf (A, Fig. 7) until the needle springs forward from
rear guard surface another . 002 - . 004 inch.
SETTING THE FRONT NEEDLE GUARD
Assemble front needJe guard (C, Fig. 5). When lower
looper is springing needle off back guard, set front needle
guard as close as possible to needle without touching.
Screw (D) is used to adjust and set front needle guard.
After this setting make sure there is no interference be-
tween needle guards and differential feed dog.
Fig. 7
Fig. 8
Fig. 9
SETTING THE UPPER LOOPER
Insert upper looper (A. Fig. 8) in its holder. Screw
(B, Fig. 8) 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 al-
ready in place. Screw (C. Fig. 8) on clamp holds the upper
looper holder in the shaft. Locate upper looper in its holder
so that the shank extends 1116 to 3132 inch beyond holder
(Fig. 8).
When the upper looper is at the right end of its stroke,
upper looper holder should be set to position upper looper
shank about vertically (Fig. 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 handwheel until upper
looper is at the left end of its travel;
check dimensions of upper looper point
with respect to 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
For example, dimension 1 I 2 inch is increased by turning upper looper
holder counter- clockwise looking from left end of machine; dimension 9I64 inch
is increased by pulling upper looper holder left, out of upper looper shaft.
After these changes are made, it may be necessary to turn upper looper around
its shank slightly to maintain the condition shown in Fig. 9.
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