Insightful sewing machine reviews

Singer 403a Slant-O-Matic Review

Singer 403a Slant-O-Matic Review
Singer 403a Slant-O-Matic Review
  • Stitch quality
  • Speed
  • Ease of use
  • Maintenance
Needs lots of help – able to sew a straight seam but unfamiliar with most sewing techniques; needs assistance and instruction on basic sewing techniques.
Competent – can make different clothing items without assistance or guidance, but not good enough to sew intricate projects or to sew without a pattern.
Expert – can sew anything without instruction or assistance; possesses an expansive knowledge of sewing techniques and terminology.


While visiting the Washington, DC area, I was able to visit Think Outside the Store, one of the most unique shops in the entire metropolitan area.

It’s a one of a kind boutique that features ecologically minded wearable art. What makes Think Outside the Store really unique, however, is the fact that the brains behind this store, Sarah Gingold, carries her commitment to the ecology to lengths most other purveyors of ecologically sound clothing and accessories probably do not.

She uses treadle and crank sewing machines almost exclusively to make the items she sells and to teach sewing classes for beginning and intermediate children, teens and adults.

The one and only electric sewing machine in the whole place is a 1958 Singer 403a Slant-O-Matic that Sarah uses primarily to teach students who are challenged by treadle or crank sewing machines.

Singer 403a Slant-O-Matic

Singer 403a Slant-O-Matic

In my opinion, she made a very good choice. Not only was the Singer 403a Slant-O-Matic a ground breaker when it was introduced, it remains one of the most durable, reliable sewing machines out there.

When this machine was introduced to the market, it opened the door for home sewers to experience many sewing advantages for the very first time.

It was the world’s first home sewing machine to offer a front drop in bobbin, a broad range of decorative stitches, and a slant needle.


  • Sturdy metal construction
  • First US made sewing machine with slant needle for home use
  • First semi-automatic sewing machine with front drop in bobbin
  • First semi-automatic sewing machine with on board thread guide
  • On-going manufacturer support through the internet and local Singer dealers


  • Interchangeable discs for decorative stitch selection – a great innovation at the time – now obsolete

At A Glance

When you look at it today, the Singer 403a Slant-O-Matic looks like any other vintage sewing machine. At the time it was made, however, this machine was the hottest thing on the market.

The slanted presser foot shank assemble was something no one had ever even thought about for home use before, and the many decorative stitch options were up to that point only something home sewers dreamed about having access to.

Before the Slant-O-Matic, slant shank presser feet and front drop in bobbins were available only on a limited number of industrial sewing machines.

The Slant-O-Matic made it possible for all these advantages to be available in every single home sewing room. It literally changed the way home sewers the world over sew.


Although the standard features offered by the Singer 403a Slant-O-Matic were pretty much unheard of in homes at the time, many of the innovative features are commonplace in today’s sewing rooms. They include:

  • 9 utility and decorative stitch options
  • Ability to sew practically anything and everything
  • Clearly written, easy to understand owner’s manual
  • Adjustable needle position
  • Reverse stitch
  • Stitch locking
  • Adjustable presser foot pressure

Working on the Singer 403a Slant-O-Matic

The spool pin

The spool pin

Winding the bobbin on the Singer 403a Slant-O-Matic is a piece of cake. Everything is literally at your fingertips. After mounting the thread on the spool pin at the base of the machine head, loop your thread through the guide next to the spool pin and up to the bobbin which is placed on the winder, less than three inches above the thread spool.

You then disengage the needle motion by holding the balance wheel and turning the stop motion dial a quarter turn toward the back. Then merely engage the foot pedal and voila… your bobbin is winding.

Threading the Singer 403a Slant-O-Matic is just as easy. Merely go with the easy to follow the on board guides and before you know it, your machine is threaded and you are ready to sew.

Double needles had not yet been introduced for home use when the Singer 403a Slant-O-Matic was made, but that didn’t stop the manufacturer.

This machine is not only equipped with the capability to sew with two needles simultaneously, it also offers three different needle positions.

Adjusting the needle position and stitch length and width are as easy as turning a dial and setting a lever at the desired position.

Adjusting the needle position and stitch length

Adjusting the needle position and stitch length

It’s probably because I have been spoiled by being able to select decorative and utility stitches with a mere touch on a LCD screen or by dialing up a desired stitch on a keypad, but for me the stitch selection process on this machine was a little bit of a challenge.

In addition to inserting the disc to achieve the desired stitch, it is also necessary to make a few adjustments to the stitch length and width and even the needle plate in some cases.

Different stitching design discs

Different stitching design discs

However, in light of the fact that I was working on the very first sewing machine that offered the home sewer any decorative stitches at all, I must admit that I was impressed by the variety of stitch options and the genius that it took to create such an innovative machine.

After all, this machine is more than 50 years old. When you think about that bit of trivia, it’s not only amazing to think that all of these firsts were jam packed into one sewing machine, it also forces one to take a second look at what we may call a challenge.

As difficult as it may be, we really have to think about the fact that the Singer 403a Slant-O-Matic is the ground breaker that it truly is and then reconsider our criticism about the stitch selection process.

Luckily, the owner’s manual was available. With the manual at hand, I was able to refer to it in order to execute the various stitches available with as little difficulty as possible.

The owner’s manual

The owner’s manual

What may be a challenge for the 21st Century home sewer was no doubt a dream come true for the home sewer of the mid 1950s. My complaint about having to take time to change discs and machine settings just proves how spoiled we have become in just a few short years.

With that in mind, and my own inability to get the hang of going through so many steps to achieve different stitches, I must admit that the stitch quality is excellent… better, in fact, than some of the newer machines I’ve had the pleasure of reviewing.


  • Natural fibers/cotton-linen-wool
  • Fine fabrics/silk-satin-taffeta/velvet
  • Knits
  • Synthetic fabrics/blends-rayon-polyester
  • Upholstery
  • Leather/suede
  • Fur
  • Reptile skin
  • Canvas/Twill
  • Plastic/Rubber
  • Extra thick fabrics or multiple layers


The Singer 403a Slant-O-Matic came with an accessories case that contained the following:

    • 8 Presser Feet
      • Straight stitch
      • General purpose
      • Special purpose
      • Button
      • Zipper
      • Rolled hem
      • Multi-slotted binder or bias tape foot
      • Ruffler
Singer 403a Accessories

Singer 403a Accessories

  • Seam guide
  • 8 Drop in fashion discs to give the user access to various decorative stitch options
  • Lint brush
  • Screw driver
  • Oil dispenser
  • Extra bobbins
  • Extra needles
  • 2 needle plates
  • Owner’s instruction manual

In addition, the following optional presser feet were also available at local Singer stores:

    • Darning and embroidery – This one is very much like the darning foot that is used in the 21st Century.

Tucker [Source :]

  • Tucker – I must admit this quite odd looking presser foot is a new one for me. This odd looking attachment has two different gages for measuring the space between tucks as well as the tucks themselves. According to the manual, users can make tucks up to one inch deep with expert accuracy.
  • Gathering – While it’s called a gathering foot, it is actually used specifically for shirring. According to the owner’s manual, anyone who uses this specialty foot will be able to expertly and quickly produce “single or multiple rows of shirring.”
  • Edge stitcher – The drawing in the owner’s manual is quite different from the edger stitchers in use today, but the results are basically the same. This presser foot is used to join fabric, inserting lace and for sewing French seams (a somewhat obsolete practice these days).

Other optional accessories include a set of 12 additional fashion discs, bringing the total number of available decorative and utility stitch options to a total of 21.


After each useMonthly*Once Each Year**As Needed
Clean race hook and feed dogs
Wipe head with soft dry cloth
Wipe head with soft damp cloth
Service by sewing machine repair professional

* more often if the machine is used for extended periods of time or if used frequently

**more often if the machine is used heavily or if it is not operating properly

Tying Off The Loose Ends

Even after nearly 55 years, the Singer 403a Slant-O-Matic remains one of the most reliable and dependable sewing machines out there.

While it is true that changing fashion discs and machine settings is cumbersome and even a bit challenging, the mere fact that this is the very first sewing machine that made front drop in bobbins, slant presser foot shank construction and lots of different utility and decorative stitch options makes this a machine worth taking a look at.

The Singer 403a Slant-O-Matic that I reviewed is used in sewing classes at Think Outside the Store in Silver Spring, MD, and not for sale.

My guess is finding one for sale is probably like finding the proverbial needle in a haystack. But that doesn’t mean they are impossible to locate. I found one on e-bay.

The asking price was $224.95, a testament to the long standing value of a machine of this vintage. Sewing machines by other manufacturers of the same approximate vintage are usually sold for far less.

An added benefit is that it is a Singer, meaning anyone who purchases a 403a Slant-O-Matic has the resources of Singer tech support at their disposal.

Any authorized Singer dealer or repair professional is fully qualified to service and repair this machine, just as they do for any brand new Singer sewing machine or serger fresh out of the box.


  1. I have a 403 special slant o matic with the manual and all those attachments/accessories pictured above that I would like to sell. Would I put it on Ebay or Craigslist? Also, does the built-in cabinet help the value?

  2. Sondra –

    Thank you for visiting Sewing Insight.

    You can certainly sell your machine on e-bay or Craigslist. I think, however, that you might also consider working with a local dealer who specializes in vintage sewing machines.

    The cabinet and the fact that you have all of the accessories as well as the owner’s manual definitely add to the overall value of your machine.

    Good luck.

  3. Great information the 403a i have one needs repair needle dose not move can you direct me a website that show to repair the 403a

  4. Hi, Carol –

    Thank you for visiting Sewing Insight. If your needle isn’t moving at all, there is a possibility that you have a problem that is best handled by a sewing machine repair professional.

    If I were you, I would not attempt to make this repair at home. Trying to fix this problem on your own could result in a much more serious problem.

    Happy stitching.

  5. Lucky me I just had one of these given to me. I am very excited about your review . I have 11 other machines and worked on a 411G recently for a friend. It could be my next work horse. Thank you.

  6. I recently purchased a 403A at an estate sale for $20 and am excited to start using it after a thorough cleaning. If it works as great as my 301A, also purchased at an e-sale (for $40), it will be another great blessing to this senior sewer.
    If one has an opportunity to purchase one, IMO, you’ll not be disappointed. They indeed are great quality!

    • I have been using this model of machine for over 20 years now. I might purchase a new machine but with as much as I sew, they usually don’t do as well as this one.

      I have even started buying extras on Ebay for the parts! This is a great machine and, with proper care, I expect it to last me another 20 years at least!

      If you ever get your hands on a working model, keep it, don’t let it go. You will come back to it time and time again for things you cannot sew on new machines, such as lambskin and leather.

  7. I found one on craigslist with a cabinet for $140! It was clean as a whistle except for fresh oil and grease. I was even given a look inside top and bottom and a maintenence lesson by the seller after my test drive! I love this machine. I have been sewing for 45 years, including factories before they all went south, have 9 machines in the back room and this is by far my favorite. I harldy ever have to roll out the commercial Consew machine on it’s 8 casters any longer. The 403A even does a great job on leather and canvas!!

  8. Many thanks for this site as I didn’t know what model I own.I was given a 403A many years ago by a friend..his sister had passed and his wife did not sew. What luck! I love it, I work with anything from leather to the sheerest of fabrics. It has only been the shop once for repair. Eight years ago I downsized to a condo. I was allowed to leave some things in the garage till I could dispose of them. I left my machine behind to be discarded and bought a table top. Within a couple of days I went running back to my old garage to retrieve my precious machine (I was making curtains)….I would “make” room for it, something else would have to go!! My only wish is that it “outlives” me.

    • Hello, Karen –

      Thank you for visiting Sewing Insight.

      You did the right thing by going back to retrieve your Singer 403a. There is no doubt whatsoever this great machine will outlive all of us. Just make sure when you write your will, you leave it to someone who will love it as much as you do.

      In the meantime… Happy Stitching.

  9. We have just recently acquired one of these machines. It did not come with the manual or the discs. Can you suggest where i might acquire these objects? Thanks

    • Try ebay.

      • Did that, can’t seem to locate an entire set of parts.

  10. Bought mine from a friend 40 years ago. What a workhorse!! Sewed halloween costurmes, dance costumes, clothing, curtains and hemmed a ton of jeans. Have had it cleaned, tuned up a couple of times. Now I am having difficulty finding bobbins to fit it at JoAnne Fabrics. Can’t find what size bobbin it requires as I look at my manual. Help?

    Another question. Has anyone had trouble with the bottom tension? My repairman says it is wearing out. I don’t want to hear that. Love this machine. Any suggestions?

    • Plastic class 66

  11. Looking for parts for the table opening. Any suggestions.

  12. I use my 403a all the time., tho I also have 5 other machines. Recently it has become noisy and thread is catching in the bobbin . I have several styles of bobbins, all fit in the 403a, but wondered if perhaps I was using one that I shouldn’t. My original users manual does not specify a bobin in size .
    Thanks for your help… I do not have a sewing machine repair center nearby.

  13. Thank you for your review. Just bought my first sewing machine which is this one. Got it from an antique store for $75. I want to make my own camping gear and it seems that this could stitch thin ripstop nylon as well as thicker Cordura.

    My question is about the double needle. While I’ll try it out soon (need to get needles), I’m not picturing how it can sew two parallel straight stitches with only one bobbin thread. Will the top thread look like two rows while the bobbin thread is one row?

    At any rate, it appears I purchased a great machine. With my practice stitches with one needle I had to figure out the right tension, but once I did, the straight and zig zag stitches are perfect.

    • Hello, Chad –

      Thank you for visiting Sewing Insight.

      Before you invest in a double needle, make sure your Slant-o-Matic can take it. I have a vintage machine, made after your Singer and the opening in my zigzag needle plate is too small to accommodate a standard double needle. If this is the case with your Singer, your question is moot. Remember… these machines were manufactured BEFORE double needles were made available for home use.

      When I want a double row of stitches in that particular machine, I just sew two rows. It really isn’t that difficult. Nor does it take that much time. The advantage is I can have as much or as little space between rows of stitches as I want.

      Happy stitching.

  14. I received a 58 403 slant and of course with my luck I broke the needle. I changed the needle with one I had from before I received this machine and now it doesn’t stitch tight. it is so loose that all I have to do is pull the thread. I did not change any settings from before the needle broke, so I would assume it would work.

    • Hello, Connie –

      Thank you for visiting Sewing Insight.

      Did you get an owner’s manual when you received your 58 403?

      Did you re-thread the machine correctly when you changed the needle?

      Is the new needle the same size as the needle that broke?

      All of these things can affect the way your machine stitches. If you do not have a manual, you can download one free of charge at

      Happy stitching.

Leave a Comment

Your email address will not be published. Required fields are marked *

Choose a Rating

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>