Your yarn, your fabric
Why the gauge step asks about your yarn — and how to answer in two minutes with things you already know.
The same yarn knits into different fabrics. Three strands of a combed merino on a 5-gauge machine give a fabric that flows and grows; the same wool, carded and knit a little tighter, holds its shape for years. Your measurements can be perfect and the sweater still slides off the shoulder — because the fabric, not the geometry, did the moving.
So before we calculate, we want to know what kind of fabric you are making. Not the brand — the behaviour. We sort every fabric into one of four classes, and the class tells the pattern where to add a bound-off edge, where to stabilise a seam, and how much ease a fitted silhouette really needs.
Nothing here requires a lab. Read the label, look at the yarn, and stretch the swatch you washed anyway.
1. How the yarn is spun — the question that matters most
Fibre content is what everyone reads first, but how the fibre was spun predicts the fabric better. Two 100 % merino yarns can behave like different animals. Look for these three families:
| Worsted-spun (combed) | Woolen-spun (carded) | Brushed | |
|---|---|---|---|
| Look | Smooth, even, slightly glossy. You can see the twist clearly. | Matte, soft, a little uneven, with a light halo of short fibres. | A visible hairy halo standing off the core. |
| Feel | Cool, dense, slides through the fingers. | Warm, airy, light for its thickness. | Fluffy; the core is hard to feel. |
| Pull it apart | Breaks with a clean end. | Drifts apart softly. | The halo pulls away first. |
| Words on the label | worsted-spun, combed, Nm 2/30, industrial cones, ‘cashwool’, most superwash merino, sock yarn | woolen-spun, carded, lopi, Shetland, ‘rustic’, tweed, carded cashmere | mohair, kid silk, angora, brushed alpaca, ‘halo’ |
| Typical yarns | Zegna Baruffa Cashwool, Lang Merino 150, Malabrigo Sock, most machine-knitting cones | Lettlopi, Jamieson’s Shetland, Holst Supersoft, Cardiff Cashmere Classic, tweed | Drops Kid-Silk, Rowan Kidsilk Haze, angora blends |
| What it does in a sweater | Low friction between loops: the fabric flows, lengthens under its own weight, opens at the shoulder. | Fibres grip each other: the fabric is springy and keeps its width. | The halo hides the core. Behaviour follows the fibre underneath — mohair with silk flows, brushed wool is springy. |
One word of warning: ‘fuzzy’ is not the same as carded. Most knitters say fuzzy and mean mohair or angora. A carded merino or a carded cashmere looks calm and matte — it is not hairy — but it is exactly the springy family we mean.
2. Fibre — the base tendency
Fibre sets the starting point; spin, treatment and your swatch move it from there.
| Fibre | Tendency | Why |
|---|---|---|
| Wool (non-superwash), BFL, Shetland, Icelandic | Springy | Crimp and scales let loops grip each other. |
| Superwash wool and merino | Flows | The scales are stripped or coated; loops slide. The most common surprise. |
| Cashmere, carded | Springy | Short, crimpy fibre, usually woolen-spun. |
| Silk, viscose, bamboo, Tencel | Flows, heavy | No crimp, no memory, lots of drape. |
| Alpaca | Flows | Long, smooth fibre with little crimp; heavy when thick. |
| Mohair, angora | Follows the core | Read the fibre it is blended with. |
| Cotton, linen, hemp | Heavy, no recovery | Plant fibres do not spring back; the fabric grows in length. |
| Acrylic, nylon | Firm to springy | Behaves like an ordinary wool in plain stockinette; the engine treats it the same way. |
3. Three more things from the label — and one from you
| Superwash | Yes, no, or ‘I don’t know’. Superwash shifts wool one step toward the flowing class. |
| Metres per 100 g | With the number of strands it tells us how heavy your fabric is — the load on the shoulder seam. |
| Gauge on the label | Optional. If your swatch has fewer stitches per 10 cm than the label suggests, the fabric is looser than the mill intended — it will flow more. Tighter than the label — it will hold better. |
| Stitch structure | Stockinette, ribbing, or texture. Any ribbing stabilises; cables and texture stabilise. Plain stockinette is the most honest — and the most mobile. |
4. Two questions for your swatch
You wash and rest your swatch before measuring anyway. While it is dry and flat, mark 10 cm across the stitches and do this:
Stretch it sideways to a comfortable maximum — not until it hurts.
| Up to about 12 cm | Barely stretches | Firm fabric |
| 12–16 cm | Stretches and springs | Springy fabric |
| Beyond 16 cm | Stretches far and easily | Flowing or heavy fabric |
Let go and watch the mark.
| Snaps right back | Memory is good. |
| Comes back slowly, within a minute | Memory is there but lazy. |
| Stays stretched | No memory — the fabric will keep whatever shape wear gives it. |
If the label and the swatch disagree, the swatch wins. It is your fabric, made your way.
5. The four fabric classes
This is what the answers add up to. You see one line on the gauge step; the pattern quietly does the rest.
| Class | How it feels | Typical fabrics | What the pattern does |
|---|---|---|---|
| A — Firm | Barely stretches, snaps back. Holds its shape like a coat. | Carded wool knit tighter than the label, tweed, cables, Shetland, acrylic in stockinette | Nothing extra. Fitted silhouettes get 2–4 cm of ease so you can move. |
| B — Springy | Stretches and returns in seconds. | Non-superwash merino, BFL, carded merino and cashmere, any ribbing | Nothing extra. Fitted silhouettes can go to zero or slightly negative ease. Heavy garments get a stabilised shoulder seam. |
| C — Flowing | Stretches far, returns slowly or not fully. | Combed smooth wool (Cashwool), superwash merino, silk blends, alpaca, mohair with silk, anything knit looser than the label | Neck edge is bound off and the collar picked up separately. Shoulder seam stabilised. Side seams required. Body and sleeve lengths shortened a little to allow for growth. A warning on drop-shoulder and wide-sleeve designs. |
| D — Heavy, no memory | Medium stretch, almost no recovery; the swatch hangs from its own weight. | Cotton, linen, chenille, heavy viscose, single-strand silk | Same construction rules as C, and lengths shortened a little more. The gauge step suggests knitting tighter than the label. |
Classes A and B leave the pattern exactly as it was — these are the fabrics the construction was designed on. The extra rules only appear for C and D.
6. What we will not ask, and what we admit
- No weights, no timers, no extra swatches. The one swatch you already knit is enough.
- The class is a guess from evidence, and you can overrule it. If you know your fabric better than the rules do, pick the class yourself — we keep your choice as a data point.
- The numbers behind classes C and D are first estimates. The first garment you knit in a new fabric is a calibration, not a failure. Measure it after washing, compare, and the next one lands closer.
Where you will meet this
On the gauge step of every pattern, right under the stitch and row counts. Answer what you know; skip what you don’t. Everything here is optional — and the more you tell us, the fewer surprises after the first wash.
Tired of counting by hand? A Knitticate pattern does all of this for you, from your own measurements.
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