This is a very good question, and one I hear often from 401, 500, and 600 owners.
This simple answer?
It depends on how creative you want or need to be. As shown on the flip-top chart, the 401 has an impressive array of built-in stitch patterns with almost infinite range of length and width variations.
Singer 401 built-in stitch chart
Singer 401A built-in cam-stack.
If you look at the 401's built-in cam stack each cam represents a different stitch pattern. And when you factor in that the 401 can "combine" two cams to create additional stitch patterns, it's pretty awesome what the 401 can do without Special Discs.
But if you want to get the maximum creative use out of your 401, you will definitely want a set of Special Discs.
Special Disc patterns from 500A manual.
The original accessories kit for the 401 included 5 Special Discs (numbered 1-5) for stitches that are not built-in. These 5 discs can be combined with the built in Primary stitches to produce additional patterns, such as scalloped zigzag.
However, Singer produced a total of 24 Special Discs for the Slant-o-Matic and 600-series Touch & Sew family, which means there are 19 additional discs available.
Some of these additional Special Discs are patterns which are not built-in, while others are duplications of stitches built into the 401. However, even duplicates can add to the range of stitches the 401 can produce.
"If it's already built-in, why would I want the Special Disc too?
The answer lies in the distinction between "Primary" patterns and "Combination" patterns.
"Primary" patterns use a single cam in the cam-stack to produce the stitch. This means that the stitch pattern is unchanged regardless of width and length settings. In other words, a scalloped stitch simply gets wider or narrower but still looks the same. In the sample shown here, the width of Special Disc #12 has been set progressively wider.
Special Disc #12 at widths 2, 3, 4, 5 (Primary)
On the other hand, "Combination" patterns use two cams in the stack to produce the stitch pattern. Which means that a change in stitch width affects the movement of both cams, which can greatly affect the overall appearance of the stitch. Note in the sample shown here how the appearance of stitch setting DP changes when the width is set progressively wider. The zigzag blocks get narrower as the offset gets wider.
Built in stitch DP at widths 2, 3, 4 (Combination)
While this does add some variety to the built-in stitches, it also means you are somewhat limited when using built-in stitch patterns if you want the pattern wider or narrower. The 401 and 500 have seven built-in "Primary patterns. They're shown on the top row of the chart (see photo above) inside the flip-up lid.
Which is where Special Discs come in. Special Discs are considered "Primary" patterns, so they look the same regardless of width. Clearly an advantage in some situations.
Another advantage of using a Special Disc is that two-needle stitching only works with "Primary" patterns, because the left-hand stitch selector has to be set on "A." So if you like the look of a "combination" stitch but want that stitch in double-needle, you'll need to use a Special Disc.
Built-in Primary patterns can also be combined with certain Special Discs to produce additional stitch patterns.
The final advantage of Special Discs is that they are just plain easy to use. Pick a pattern, pop it in, and away you go. No messing with dials or charts.
So, DO you need a complete set of Special Discs for your 401, 500, or 600 sewing machine?
Bottom line, it's up to you. The choice is yours.
Happy Sewing! Barbara OldSewinGear...dedicated to helping you get the most our of your old sewing gear.
One of our readers asked how to reassemble the stitch-length adjustment knob on her 503 Rocketeer. She took hers apart to clean it and then encountered a problem getting the pieces back together. I didn't know the answer either, so I went and asked the resident expert. He explained it to me and I went and tried it out for myself and took some pictures and videos to share.
Without further ado, here's how to reassemble the 500/503 stitch-length adjustment lever knob. First we'll look at taking it apart and then we'll look at putting it back together.
The lever has a knurled knob on the end that tightens up against the face plate to select the desired stitch length.
There are two wings on the lever that slot into the notches at the "fine" selection and the "6" selection to lock those settings into place.
To disassemble the knob, use a standard screwdriver to remove the screw at the end of the shaft. Then pull the whole knob assembly toward you. It will slide off along with the small washer that sits on the end of the shaft between the screw and the knurled knob.
The winged piece screws up inside the knob and will have to be unscrewed for proper cleaning and lubricating.
When you've finished disassembly the knob, you'll have four pieces as shown at left. Next, a light application of lubricant on the inside the knob will aid in reassembly.
Putting the knob back together can be a bit tricky because threading the winged piece back into the knob works opposite from the old "lefty-loosey, righty-tighty" principle.
Start by holding the winged end in your left hand. Then take the knob in your right hand and screw it onto the end of the winged piece, turning it toward you. This is best shown in video:
Next the winged end will be inserted into the slot on the lever and the washer and screw put back in place. Again, this is best demonstrated in video:
As you can see, it only took a little bit of fumbling to get the pieces back together. Believe me, it will be a lot easier if one hand isn't tied up holding a camera!
And there you have it. Make sure everything is firmly tightened and your knob will be good as new.
Happy Sewing! Barbara
OldSewinGear...dedicated to helping you get the most out of your old sewing gear.
First, select the stitch pattern you want to use. There are 24 discs available for the Slant-o-Matic and early Touch & Sew machines. They are numbered 0-23, with 0 being standard zigzag and 23 being basting stitch.
Next, open the lid on the top of your machine:
Check to see if there is already a disc in the machine:
500 disc compartment WITH disc
500 disc compartment WITHOUT disc
Singer 401 stitch selector knob.
If there is already a disc in the machine, you will need to remove it before inserting the disc of your choice.
To remove or insert a disc you may need to adjust the knob or lever settings on your machine.
If you have a 401, 411, 500, or 600 model, make sure the stitch selector is NOT on "Special."
Singer 600 stitch selector levers
Singer 500 stitch selector knob
403 stitch width lever
If your machine is a 403, 503, or 603 model, set the stitch width lever to "S" or "STR".
Grasp the raised center portion of the disc firmly and pull straight up. There's no special trick to this. As my dad always says, "Pull hard and it'll come easy."
Now you're ready to insert your chosen disc. Line up the holes in the disc with the two posts in the disc compartment.
Press disc firmly into place. There should be a slight click when it's fully seated.
Let's look at it in motion:
Next, readjust knobs & levers for Special Disc sewing.
For 401, 411, and 500 machines, set large center knob at "B" on the left and "Special" on the right. For 600 machines, set the upper stitch selector lever at "Special" and the lower stitch selector lever at "B". Then set stitch width lever to desired width.
For 403, 403, and 503 machines, set stitch width lever to desired width.
Finally, adjust the stitch length lever to desired density. Special Disc patterns typically look best when sewn at the shortest stitch length possible.
That's it! You're ready to sew. It's really that easy.
Happy Sewing! Barbara OldSewinGear...dedicated to helping you get the most out of your old sewing gear.
When Singer introduced the 500 Slant-o-Matic Rocketeer, it featured a new threading step that Singer called a "thread control."
So what is it? What does it do?
Singer 500A "Thread Control"
"The automatic thread control, located above the tension, ensures a smooth flow of thread from spool to needle. This device eliminates spool weight and drag by pulling off a measured amount of thread before it passes through the tension discs."
So there you have it straight from the horse's mouth! Thread control is clearly the greatest invention since sliced bread!
So this thread control was a giant leap forward in sewing machine technology, right?
Ummm...not so much, because there's no noticeable difference in stitch quality when comparing the 401A and 500A. Singer apparently came to the same conclusion, because "thread control" disappeared after the early 1960's. It does appear on the German-built 401 and 411 models but then Singer went on to produce the "Touch & Sew" series with a horizontal spool spindle which eliminated spool drag completely.
Alternative threading for Singer 500A
Thread control was so underwhelming that Singer went so far as to distribute an alternate threading guide for the 500 that bypasses the thread control. This threading chart was included in the "Knit Kit" that Singer produced for sewing double-knit fabrics.
I've experimented with both threading methods and I prefer to bypass the thread control because it's faster. And the stitches look just as good without it.
So there you have it...thread control. No, it didn't revolutionize sewing machine technology, but it's still a cool feature that sets the Rocketeer apart.
October 1957...Russia launches Sputnik, and the whole world goes into orbit...
America went crazy for "Space Age" style and Singer's response was the redesigned Slant-o-Matic, fondly called "The Rocketeer."
With sleek, futuristic lines, cool knobs, and rocket-motif levers, the 500-series was one small step for Singer, one giant leap for...well, you get the picture!
Launched in 1961, the 500 series introduced features not included on the early 400 series Slant-o-Matics. These included top-mounted enclosed bobbin winder and an additional "thread control" lever. A previous post, "Which is better? Singer 401 vs. 500 Rocketeer" discusses the differences in a side-by-side comparison of the two models.
The new Slant-o-Matic came in two models, 500 and 503. So how do they stack up against each other?
Both machines are heavy duty powerhouses with the ability to sew straight-stitch, zig-zag, & decorative stitches. When properly adjusted and equipped with correct needle and thread, both machines will sew leather, denim, canvas, or vinyl.
As with the 401 and 403, the fundamental difference between the 500 and 503 is in HOW the machine sews zig-zag and decorative stitches. The 500 has decorative stitches built-in. The 503 requires Special Discs to produce any stitch other than straight stitch.
Let's take a look side by side with 500 on the left, 503 on the right:
Slant needle Rotary hook Steel Gears Drop-in Class 66 bobbin .72 Amp direct drive motor Double-thread capacity tensioner Double capacity needle clamp Thread control regulator Special Disc compartment Removable top-mount spool spindle 2 fold-flat spring-loaded spindles --- 25+ stitch patterns built-in
Slant-o-Matic 503A Special
Slant needle Rotary hook Steel Gears Drop-in Class 66 bobbin .72 Amp direct drive motor Double-thread capacity tensioner Double capacity needle clamp Thread control regulator Special Disc compartment Removable top-mount spool spindle 2 fold-flat spring-loaded spindles --- No built-in stitch patterns
Almost immediately you notice that the 500 has a large knob in the front and the 503 does not:
The large knob on the 500 is the selector for built-in stitches. A look inside reveals the cam-stack that produces these stitches on the 500 and the absence of the cam-stack on the 503:
Since the 503 does not have any built-in cams, it relies entirely on Special Discs to produce zigzag and decorative stitches. Once a Special Disc is inserted, the 503 is capable of producing beautiful decorative stitches using single or double needles.
On the other hand, the 500 has the capability of combining built-in stitches with Special Discs to create additional decorative patterns. (For more information on built-in stitches vs. Special Discs, see the article "Do I need Special Discs for my 401 or 500?")
So which Rocketeer is right for you? That depends on your sewing needs. If you want simplicity with the option to occasionally sew decorative stitches, the 503 will suit you perfectly. It is very easy to operate and typically a little quieter than the 500 since it has fewer moving metal parts.
But if you want maximum creative flexibility and don't mind learning how to use the knobs and charts, then the 500 is the better choice.
Whichever model you choose, you'll be 'over the moon' once you own a Rocketeer!
On a lighter note, my family reserves the term "Rocketeer" for the 500. Our nickname for the 503 is "Purtineer." Almost a full-fledged Rocketeer, but not quite!
OldSewinGear is the collaborative effort of retired repairman Gary and daughter Barbara. We love old sewing gear and enjoy sharing what we've learned in our vintage sewing machine adventures. We are located in Roseburg, Oregon.