All about the discs
Here is the information I've been able to collect from various sources.
As far as I know, there's no list of official names for the various discs; they're only identified by number. If someone can point me to a sources of proper names, I would appreciate it.
Contents:
Single Discs
The single pattern discs have a sequence of lobes around their perimeter that control the position of the needle, left or right, as the machine stitches. The stitch width control also comes into play here, controlling the width of the pattern. Set the stitch width lever to zero, and you might as well not have a pattern disc in the machine at all.
The stitch length control also is used here, just as with straight stitch. Adjusting the stitch length control spreads the pattern out or squishes it together. You'll want to pay attention to this control, as many of the patterns only look right if the control is set correctly for that pattern.
coming soon: some example photos.
Discs in this section:
03 — Zig-Zag
I list this one first since it's the most important disc you can own if you have a Supermatic machine. (More modern machines such as the Elna Air series have a built-in zig-zag stitch so you don't need the disc.)
Let's face it, in the real world, 90% of the sewing you ever do will be straight stitch, and 90% of everything else will be zig-zag. Sure, you might dig out disc 134 and sew some duckies to show your friends what the machine can do, but you're never going to use it in an actual garment. (Except now you will, just to prove me wrong. Whatever.)
But zig-zag is one you'll use all the time.
If you own a Supermatic, this is the one true "must have" disc. Your machine should have come with this disc (along with some others). There's a chance that some previous owner removed the disc to sell separately. You might want to refuse to buy the machine if there's no zig-zag disc, but I appreciate that it might be hard to find a machine with this disc. (I'll tell you this much: I've sold a number of Supermatics, and I always include disc 03 and a few others when I sell one.)
If it comes down to it, you can likely find the disc for sale at eBay or Etsy. A simple search for Elna pattern cam may be very fruitful. I found that M&R Sewing and Vacuum (no affiliation) has a decent collection.
If you have access to a 3d printer, you can find the STL file at Thingiverse.
Things you can do with a basic zig-zag stitch:
Stretch fabric
If you stitch stretch fabric with a straight stitch, you create a place where the fabric can't stretch because of the stitching. If the fabric tries to stretch at that point, it will pull and distort, or worse yet, the thread will break.
Instead, sew with a zig zag stitch. Adjust the stitch width and length so that the zig-zag pattern is roughly at a 45° angle. This gives you a stitch that stretches with the fabric.
Edge Stitching
If you don't own a serger (I never have), you may find yourself from time to time needing to stitch along the edge of the fabric in such a way to keep it from fraying.
One way to do this is to sew a zig-zag pattern near the edge of the fabric. The stitching keeps the fabric from fraying. Once sewn, you can trim the fabric close to (but not cutting!) the stitching. You can also place your stitches close to the edge of the fabric. If you do this, there's a chance that the stitches will pull the fabric in, which is unsightly. An overcast foot has a small metal bar that prevents this from happening. When using one of these, be careful to have the stitch width set correctly to make sure the needle doesn't come down on that metal bar. Take a few stitches by hand before applying power. Here is a short tutorial on the subject: How to Use the Overcast Foot.
With the stitch width and stitch length set very small, you create what is known as a "satin stitch". This can be used to finish the edge of something delicate such as a handkerchief. It can also have a purely decorative purpose.
Finally, by running two satin stitches close together, with a bar tack (basically a wider satin stitch) at the ends, you have a button hole. Here is a short video that shoows how it's done.
01 — Stepped Zig-Zag
Looks like disc 03, above, but each zig-zag is actually multiple stitches. You'll need to set the stitch length much shorter to get the same visual effect. This can give a tighter stitch than disc 03. It can be used with stretch fabric as above, but many of the other effects won't work.
02 — Sine Wave
Another side-to-side stitch like zig-zag or stepped zig-zag, but a sine wave pattern instead of a triangle wave pattern.
04 — Long Scallop
05 — Scallop
06 — Zigzigzag
10 — Blind Hem
The blind hem stitch is used in combination with a blind hem foot. You fold the hem of your garment in a special way and use the blind hem foot* to hold its position properly. The result is a stitch where one stitch out of six just barely catches the fabric where it can be seen.
(* The guy who taught me how to sew called it a "micrometer foot".)
11 — Arrows
12 — Heavy sawtooth
13 — Step zig
16 — Waveform
17 — Round pulses
18 — Scallop
20 — Square pulses
33 — Hi-lo zigzag
Double Discs
Discs in this section:
This is not a complete list. I've only included the ones for which I have any information other than what you can see in the chart above. In some cases, I've linked to videos that show the disc in action.
101 — Turkish Hemstitch
Also sometimes called the Turkish Point Hemstitch. Here is an article on using this disc, along with a wing needle to complete the effect.
102 — Loops
103
106 — Cross stitch
107 — Wheat
I call it that because it looks like wheat. As always, I have no idea what the actual name is, if any. Purely decorative.
109 — Chevrons
Purely decorative. I could probably come up with a better name.
110 — Crosses
Purely decorative.
115
Decorative; could also be used with stretch fabric.
125 — Tricot
A very pretty decorative stretch stitch. Set the stitch width to zero to get a stretchable straight stitch.
134 — Duckies
Probably the most popular of the double pattern discs. If your machine came with any cams at all, it probably came with this one.
135 — Birds
136 — Dogs
137 — Sailboats
138 — Bells
Or maybe morning glories?
139 — Butterflies
140 — Asterisks
141 — Locking Zig-Zag?
142 — Doilies
Some might call them asterisks
143 — Bushes
146 — Superjersey
My notes call this "superjersey". I confess I can't remember where I got that.
148 — Herringbone
I don't know if that's the best name for it; it's what I wrote in my notes.
149 — Overlock
Generates an overlock stitch which can be used to keep the edge of fabric from fraying. An overcast foot can be used with this stitch for best results.
Here is a short tutorial on the subject.
150 — Long Superjersey
151 — Darning
This one is a little tricky. It does a long back-and-forth stitch used for darning. You drag the fabric slowly under the foot to get the effect you need. See p.45 in the Supermatic manual.
152 — Superstretch
154 — Pattern of X's
Decorative.
155
156
162 — Box Stitch
Used along with a wing needle to make decorative hem stitches. Tutorial.
163 — Double Overlock
This video shows how this disc can be used to repair a cut in fabric.