The 500A was the top of the line, followed by the 503
The 400 series was produced before the 500's, with the 401A being the top of the line.  Followed by the 403, then the 404
Schematics
500A Schematic
401A Schematic
503 Schematic
403A Schematic
404 Schematic
Machine Tips
Tip on Bobbin Usage for all Slant-O-Matic
Tip 1 on new way to thread the machine
Tip 2 on new way to thread the machine
Is your machine having problems with not making a full zig zag, or other patterns?  Perhaps the needle bar area
is gummed up - This might help
I think I need to clarify the "new threading" of the Slant-O-Matic, as I've received a few queries on it.
This method actually started back in the mid 70's, when Singer introduced the Knit Kit (see above) for the Slant-O-Matic.
And perhaps you are already threading your machine this way.  But if you are threading the machine per the Instruction Book, then
you might wish to consider the new method as an option, along with the use of the 66 class plastic bobbins.
Counter
$12.00
500A-M - Service Manual for Slant-O-Matic 500A & 503 machines
44 Pages on adjusting the machine - This will certainly help you keep your machine in tip-top shape
This manual is available as a download only, so you can start your repair project right away.  The file
is approximately 13megs in size.   By the way, this same book would apply to the 401A.  The
machines are the same internally, just frame/casting design differs, plus the bobbin winder area.
No Hard Copy will be sent - Download Only
172336 - 66 Class Plastic Bobbins - pack of 10 - Fits:
All Stylist Series machine - 66 Class - Slant-O-Matic - Fashion Mates with drop in bobbin
Update: 1/21/07 - just tried some of these in one of my machines - If you have problems with them let me know, they
may require a little fine tuning yet.  Mine were sticking in the bobbin case, not spinning smoothly - needed to take a
little off the edge of them
Item Is Pending removal due to defective performance - if you ordered, or order - let me know how they work.  This
was in an Apollo Bobbin Case System, may be fine in a Metal Bobbon Case like the Slant-O-Matics
$4.25
In Stock
 Yes Usually ships in 2-3 business days
163477WS - Replacement Slide Plate with matching spring
The original slide plate used on the Slant-O-Matic series is the same size as the 600 Series Touch & Sew
However the spring was different.  This replacement plate comes with a matching slide plate spring to ensure
proper fit on your machine - Fits all 500A - 503 - 401A - 403 - 404 models
 $15.30
In Stock
Yes Usually ships in 2-3 business days
172200 - General Purpose ZigZag Needle Plate  (See other notes about this plate)
Fits all Slant-O-Matic Machines - 500A - 503 - 401A - 403   Does not fit the 404
 $9.50
In Stock
 Yes Usually ships in 2-3 business days
SR-401 Instruction Book - Singer 401A  -  Book is a scan copy as received from the vendor
Hard copy will be mailed, but you may download your manual after checkout, so you may find the
information needed right away
$11.95
In Stock
No Usually ships in 2-3 business days
Bobbin Case Removal 401 - 403 - 404 - 500A - 503
Threading 401 - 403 - 404 - 500A - 503 Parts ID
Checking Hook Point for Burr's
Threading Chart Provided with the Knit Kit
Threading Guide from a 403 Door Panel Plate
Tip 3 on new way to thread the machine
Pattern Dial Plate from a 401A, applies to 500A also
400 Motor & Wiring
$24.95
172550 Bobbin Winder Unit
For: 500A & 503 only - Normally found broken right where the screw mount to the
machine frame is located.  No Return Spring Included, winder only
In Stock
 Yes Usually ships in 2-3 business days
SR-500 Instruction Book - 500A & 503 - Book is a scan copy as received from the vendor
Download copy not available at this time, a hard copy will be mailed
 $11.95
In Stock
 No Usually ships in 2-3 business days
Instruction / Owners Manuals
Parts - Repair Manual 401 - 403 -404 & 500 - 503
172509 Spool Pin for the 500A & 503 Machines Only
$1.20
In Stock
 Yes Usually ships in 2-3 business days
172512 Spool Pin Return Spring for 500A & 503 Machines
Normally one might find the spring from a broken spool pin inside the machine, but if not, here are replacement
springs.  Required to lift the spool pin up for sewing when the top lid is opened
 $3.75
In Stock
 Yes Usually ships in 2-3 business days
$1.10
172203 (174124 updated part number) Rubber Base Cushion / Foot Peg:
Fits all Slant-O-Matic and T&S 600 and 700 Flat Bed Series
Sorry, I do not stock the screws for the cushions
In Stock
 Yes Usually ships in 2-3 business days
15287A Standard Bobbin Winder Friction Ring / Tire
For all Slant-O-Matic's, 500A - 503 may require minor adjustment to the stop lever,
These are just slightly larger than original
$1.00
In Stock
 Yes Usually ships in 2-3 business days
172075 Presser Foot - ZigZag
Fits: 401A, 403 & 500A - 503 Slant-O-Matic's - shank is included
Note: This foot does not snap on/off the shank like T&S machines
 $5.50
In Stock
 Yes Usually ships in 2-3 business days
$10.00
194407-002 - Rubber Base Cushion for older Singer Foot Controllers (sold in sets of 4)
In Stock
 Yes Usually ships in 2-3 business days
$19.95
196221 - Light Socket Assembly
Fits 301 - 401A - 403 - 404 & pretty sure the 500A & 503 are the same units
In Stock
 Yes Usually ships in 2-3 business days