IDENTIFICATION OF MACHINES
Each UNION SPECIAL machine is identified by a style number, which is stamped into the style plate affixed
to the middle of the machine under the tension assembly. The serial number is stamped into the serial
number plate affixed to the right rear base of the machine.
CLASS DESCRIPTION
High speed streamlined long arm needle feed lockstitch machines. one needle, light, medium and heavy
duty, continuous running roller feed, rotary hook, horizontal hook shaft, gears for changing stitch length, slot
s e g m e n t f o r a d j u s t i n g n e e d l e f e e d , 1 1 / 4 i n c h n e e d l e b a r t r a v e l , o n e r e s e r v o i r e n c l o s e d a u t o m a t i c
lubrication system, head oil siphon, adjustable hook oil control, needle bearing for take-up lever and needle
bar driving link, needle feed timing on upper shaft, maximum work space to right of needle bar 8 inches.
STYLE OF MACHINES
63900AM
For making 3/8 on 1/2 inch turned down hem on legs of overalls, coveralls, and dungarees.
Seam Specification 301-EFb-1 inverted, Specify size of hem. Maximum recommended speed
5200 R.P.M.
63900AML
Same as 63900AM except includes a hook with 52% greater bobbin capacity to reduce
frequency of bobbin changes.
63900AT
For making a 1/2 or 2 1/2 inch hem turned by hand on children's wear, men's dress pants,
semi-dress pants and work pants. Sewn when garment reaches machine inside out. Seam
Specification 301EFb-1 or EFa-1. Maximum recommended speed 5200 R.P.M.
63900AW
For top stitching waistbands on twill and woolen pants. Machine equipped to sew over belt
loops. Fitted with cloth plate extension. Seam Specification 301-SSa-1. Maximum recom-
mended speed 5200 R.P.M.
63900AAE
Same as Style 63900AW, except fitted with spring guide keel on presser foot in line with
centerline of needle hole.
ILLUSTRATIONS
This manual has been arranged to simplify ordering repair parts. Exploded views of various sections of the
mechanism are shown so that the parts may be seen in their actual position in the machine. 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 in the particular view being shown.
Numbers in the first column are reference numbers only, and merely indicate the position of the part in the
illustration. The reference number should never be used in ordering parts. Always use the part number listed
in the second column.
Component parts of sub-assemblies which can be furnished for repairs are indicated by indenting their
descriptions under the description of the main sub-assembly. As an example refer to the following text.
18. 29126EL Needle Feed Driving Eccentric and Connecting Rod Assembly ................................. 1
19. 22894J
Set Screw .................................................................................................................. 2
6
