UnionSpecial 39500 Series Instruction sheet

F IN EST QUALITY
STYL E
39 SOO MG
CATALOG
No.
103MG
®
INDUSTRIAL
SEWING
LEWIS • COLUMBIA
MACHINES
CLASS 39500
HI -S TYLED HIGH SPEED
SINGLE NEEDLE TWO THREAD
PLAIN FEED S ERGING MACHINES
FOR PRECLOSED TROUSER CUFFS
· CHICAGO
From the library of: Superior Sewing Machine & Supply LLC

Catalog No. 103 MG
(Supplement to Catalog No. 103 FJ)
INSTRUCTIONS
FOR
ADJUSTING AND OPERATING
LIST OF PARTS
CLASS 39500
Style 39500 MG
First Edition
Copyright 19 7 2
by
Union Special Machine Co.
Rights Reserved in All Countr i es
MACHINE COMPANY
INDUSTRIAL SEWING MACHINES
CHICAGO
Printed in U.S.A.
2
February, 1972
From the library of: Superior Sewing Machine & Supply LLC

IDENTIFI C ATION OF MACHINES
Each Union Special machine is identified by a Style number on a name plate on
the machine. Style numb e rs are classified as standard and special. Standard Style
numbers have one or more le tters suffixed, but never contain the letter "Z".
Example: "Style 39500 MG". Special Style numbers contain the letter "Z". When
only minor changes are made in a standard machine, a "Z" is suffixed to the stand-
ard Style number. Example: "Style 39500 MGZ".
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 FJ and should be used in con-
junction therewith. Only those parts used on Style 39500 MG, but not on Style 39500
F J 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 number
listed in the second column.
This catalog applies specifically to the standard Style of machine as listed herein.
It can also be applied with discretion to some Special Styles of machines in Class
39500. Reference to directions, such as right, left, front, back, etc., are g iven
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 Single Curved Blade Needle, One Looper, One Spreader, Two
Thread Serging Machine. Plain Feed, Trimming Mechanism with Spring Pre s sed
Lower Knife, Automatic Lubricating System.
39500 MG Light to medium duty machine for serg i ng around pants cuff before cuffs
are folded and similar operations on light, medium and heavy weight trouser
material. Seam specification 503- EFd-1; standard seam width 3/16 inch; stitch
range 4- 8 per inch; cam adjusted feed. Maximum recommended speed 7000
R. P.M.
OILING
CAUTION! Oil was drained from machine when sh i pped, so reservoir must be
filled before beginnin g to operate. Oil capacity of Class 39500 is six 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 bulb on oil level ind i cator should show between g auge
lines when machine is stationary.
Machine is automatically lubricated. No oi li ng is necessary, other than k ee ping
main reservoir filled. Check oil daily before the morning start; add oil as required.
The oil drain plug s crew is located at back of machine near bottom edge of base .
It is a ma g netic screw designed to accumulate possible foreign materials which may
have enter ed the crank case. It should be remov ed and cleaned per i odically.
3
From the library of: Superior Sewing Machine & Supply LLC

NEEDLES
Each Union Special needle has both type and size number. The type numb er
denotes the kind of shank, point, length , groove, finish and other details. The siz e
number, stamped on the needle shank, denotes largest diameter of blade, measur -
ed 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.
Class 39500 machines use a curved blade needle. The standard recommended
needle for Style 39500 MG is Type 154 GAS. Below is the description 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, 049, 054, 060.
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 GAS, Size 044".
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 are -
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 bushin g (AG,
Fig. 1) and swing presser arm (U) out of position. Turn handwheel in ope rating
direction until needle is at its lowest point of travel. 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 high position; withdraw needle.
To replace needle, leave needle holder at high position and, with the flat to the
left, insert needle in holder until it rests against stop pin. Keeping needle in this
position, turn handwheel until holder is again at its low point of travel; then tighten
nut. Return presser arm (U) to position andre-lock presser foot release bushin g (AG).
THREAD STAND
After thread comes from cones on cone support (A, Fi g. 1), it is brought up
through back hole of thread eyelet (B), then down throu gh the front hole of thread
eyelet. Next it is t hreaded through the upper holes of tension thread guide (C) from
front to back and then through the lower holes from back to front. Threads then
continue between tension discs (J), through tension post slot (K) in tension post (G)
and on throu gh front thread guide (M).
4
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m Tension Nut ~
IJ Tension Sprin g Fe rrul e
II Tension Sprin g~
[!] Tension Post ( ~~ -SJ ~ ~
IIJ spring Shield .. .
DTension
Discs ·.··
(I Tension Post Slo ~ --
II Tension Disc Felt·-..
[i Tension Thr ead Guide
~ Front Thr ead Guide
·, 0
IIJ Upper Looper Thread Eyelet
(il Auxiliary Looper Thread Eyelet
m Presser Arm
Fig. 1
-Needle Thread
Pull-off
5
~----- B Cone Support
Upper Looper
Thread Tube Assembly
Upper Looper
a Lower Spreader
From the library of: Superior Sewing Machine & Supply LLC