Knitwear and jersey, when the fabric makes itself

01Cut-and-sew and fully fashioned are two different routes

Two common routes are cut-and-sew and fully fashioned knitting. Choose the route during early design because it affects the shape, specification and costing. In cut-and-sew, knitted cloth is produced by the metre, relaxed, laid up in plies, cut to pattern pieces and sewn together. A t-shirt, a sweatshirt, a jersey dress and most leggings are made this way. In fully fashioned knitwear, panels are knitted to shape by increasing or decreasing stitches and then joined. Whole-garment knitting is a further route that can knit the garment in one piece, although some designs still need additional sewing or finishing.

A jersey factory buys cloth. A knitwear factory buys yarn and makes the cloth and the garment in one operation, which is the whole of the difference in a sentence. So a range drawn without the distinction treats a jumper as a heavier t-shirt, and that plan does not survive the first conversation with a factory. Changing a jersey style is a pattern change against cloth that already exists. Changing a fully fashioned style means writing a new knitting programme, size by size, often in a different yarn.

A third route sits between them. Sweater panels can be knitted as flat blankets and then cut and sewn like any cloth, which looks like knitwear and behaves commercially like cut-and-sew. What it gives up is the shaped edge: no fashioning at the armhole, cut edges that have to be secured, and more yarn consumed for the same garment.

02A cut edge has to be secured and a knitted edge closes itself

The clearest place to see the difference is where a panel ends. In cut-and-sew the edge is made by a blade passing through many plies of relaxed cloth. Every loop the blade meets is opened, so the edge is unstable: single jersey curls towards its face and a cut course can run. It has to be secured, which is why an overlocker trims, wraps and sews in one pass.

The seam then has to move as far as the fabric does. An overlock wraps looper threads around the edge, and a coverstitch lays parallel needle threads over a looper thread underneath; both structures let the seam extend and return with the cloth. A lockstitch made with unsuitable thread or stitch settings can break before the jersey reaches the extension needed in wear. Choose thread, stitch density and seam construction together, then test the seam's extension and recovery.

On the fully fashioned route nothing is removed to make an edge. Stitches are transferred inwards, or added at the selvedge, while the piece is knitting, so the loop structure runs continuously to the boundary and closes itself. Those small diagonal marks inside the armhole of a well-made sweater record where stitches were moved. Joining follows from that: linking places one loop of one panel over one loop of the other along a points bar, so the join is a single course of stitches, flat and continuous with the fabric either side. It is slow and skilled. Overlocked make-up on a knitted panel is quicker and leaves a bulkier seam that shows at the shoulder and the neck, where it is felt as well as seen.

03Cost follows the cloth on one route and the machine on the other

On cut-and-sew, cost follows the cloth. The controlling number is how efficiently the pattern pieces nest in the marker across the width of the fabric, because the gaps between them are paid for and never become garment. Adding a style to a jersey range adds a pattern, a marker and sewing time; it does not usually add a new material commitment, because the new style draws on cloth that has already been bought.

On fully fashioned, cost follows machine time. A knitting machine works in courses, so the time a garment takes is close to the number of rows it needs, and the number of rows depends on how small the loops are and how large the body is. A larger size takes meaningfully longer to knit than a smaller one, which is not how a cut garment behaves, and make-up is a real share of that cost rather than a rounding.

Those two structures push a range plan in opposite directions. Shared jersey cloth can support several styles, but each still needs development and sewing work. Fully fashioned styles add knitting-programme development across the size range. Both routes benefit from a focused range and a palette that fits the material minimums. How quantity changes what is possible sets out how a change in the order reopens material decisions that looked settled.

04What a specification must carry on each route

A cut-and-sew jersey specification is a woven garment specification with stretch added to it. The anatomy is familiar: material, points of measure, seam and stitch types, seam allowances, trims, labels and care. What it adds is behaviour. The cloth needs its construction named, its weight, its finished width, the direction and amount it stretches, how much of that it takes back, and how far it moves after washing. Construction here means the actual knit: single jersey, interlock, rib, French terry, loopback fleece.

A fully fashioned specification is a different document. It has no fabric line at all, because the fabric and the garment are made together. It carries the yarn, the gauge, the stitch structure area by area, the stitch and row counts that produce the shape, the fashioning itself, the trims at welt, cuff and neck, the make-up seam by seam, and the finishing route that brings the garment to the state in which it will be measured.

Material

Cut-and-sew names a cloth, bought by weight and width. Fully fashioned names a yarn: fibre, blend, count, ply and twist. On the knitting route the yarn is the material and the cloth is an outcome of the programme.

Structure

Cut-and-sew states one knit construction for the whole cloth. Fully fashioned states a structure for every area: body, sleeve, welt, cuff, collar and any panel that differs, with the transitions between them.

Dimension

Both carry points of measure and the method for taking them. Fully fashioned also carries the stitch and row counts behind those measurements, because a knitting machine works in stitches and rows and not in centimetres.

Shaping

Cut-and-sew shapes with a pattern line. Fully fashioned shapes by losing or gaining stitches at a stated rate and position, which is visible on the finished edge and has to be drawn as well as counted.

Make-up

Name the join at every seam. Linking sets loop against loop for a flat, low bulk join and is paced by an operator. Overlocking is quicker and reads heavier at the shoulder and the neck.

Finishing

State the wash, steam or press the garment passes through, because that operation sets the final handle and the final dimensions. A garment measured before it is finished is measured too early.

The two documents are not interchangeable. A jersey specification handed to a knitter leaves every question that matters unanswered, and a knitwear specification handed to a sewing factory asks for information it has no way to use. The general method behind both sits in What to decide before a specification, and the route decision belongs upstream of everything in it.

05Gauge constrains yarn choice and stitch scale

Gauge is the number of needles per inch on the needle bed. A coarse gauge has fewer, larger needles and takes thicker yarn; a fine gauge has many small needles and takes fine yarn. Gauge constrains the available yarns and stitch scale. Yarn count, stitch length, structure and finishing then work with it to determine weight, warmth, opacity, handle and stretch; gauge alone cannot predict the finished cloth.

Handle and drape follow from the same place. A coarse fabric is thick relative to its area, so it resists bending, holds a shape and makes volume out of its own structure. A fine fabric bends easily and falls, taking the shape of what is under it. Gauge also decides the shaping increments available, since a slope is made by losing whole stitches: a coarse gauge shapes in visible steps and a fine gauge shapes almost invisibly.

Stitch structures are constrained by the same number. A cable crosses groups of stitches over one another and needs bulk to read as relief, so it wants a mid to coarse gauge; at a fine gauge the same crossing becomes a texture. Small motifs need enough stitches to resolve the intended detail. Jacquard, pointelle and intarsia can be made at different gauges, with different visual scales. Pace moves with it too: halving the loop size roughly doubles the rows needed for the same length.

This is why gauge belongs to range planning and not to detailing. A silhouette drawn for a fine, flat, close rib and then knitted at a coarse gauge is a different garment: proportions change, trim depths change, weight changes, and the shoulder falls in a new place. On cut-and-sew the equivalent decision is fabric weight, and it behaves the same way. The order product decisions have to happen in places both among the choices that other choices depend on.

06The yarn behind the handle is a specification, not a fibre name

A fibre name predicts almost nothing about a finished knit. Two wool yarns of the same weight can produce a smooth, dry, sharply defined fabric and a soft, hairy, blurred one. The difference is in how the yarn was made. Worsted spinning combs the fibres parallel and removes the short ones, giving a lean yarn that holds stitch definition and sheds fewer fibre ends. Woollen spinning keeps the fibres lofty and disordered, giving warmth, softness and a surface that fills in the stitch.

Count, ply and twist finish the description. Count states thickness. Ply states how many strands are twisted together, and more plies at the same total thickness make a rounder, more even yarn and therefore a cleaner stitch. Twist sets the rest: a harder twist gives strength, definition and a drier hand, while a softer twist gives loft and a surface with more fibre ends free to migrate and pill.

On cut-and-sew these decisions are already inside the cloth, so they are chosen as cloth characteristics: weight, construction, finish and any surface treatment applied afterwards. It is worth knowing they are there, because two cloths at identical weight and identical fibre content can pill differently, print differently and recover differently. The most expensive decision is not the fabric holds the wider version of that argument.

07Measure a knitted garment in a defined relaxed state

A knitted fabric has no fixed dimensions. It is a structure of loops that extends under load, contracts when released, and takes time after knitting and finishing to settle into the size it will keep. A measurement therefore means nothing until the conditions of measuring are recorded beside it.

The method matters. Let the garment rest after finishing, for a stated period, in ordinary room conditions; a garment straight off the machine or out of a dryer is not at its size. Lay it on a flat, clean table and square it, so the centre front, the fold and the shoulder points are symmetrical. Smooth it outwards from the centre with the flat of the hand and then let go, so the fabric settles rather than being held. Lay the rule flat and read the defined point edge to edge, without pressing the tape into the surface. Never pull a knitted garment to reach a number on a sheet.

Some measurements need two values. A waistband, a cuff and a neck opening should be recorded relaxed and extended, because relaxed describes how the garment sits and extended describes whether it goes on at all. A neck opening measured only at rest can pass a specification and still fail over a head.

Tolerances on knitwear are wider than on a cut woven garment, and the reason is mechanical. On the fully fashioned route the garment is dimensioned in stitches and rows, so the smallest available change is one stitch or one row: measurements move in the increments the machine allows and not the increments a pattern would allow. On cut-and-sew, panels relax after cutting and the roll has to be relaxed before it is laid, or the finished garment comes out smaller than the marker promised. How to read a garment sample covers the wider inspection around those numbers.

08Test growth, recovery and shrinkage on the fabric itself

Three behaviours decide whether a knitted garment still looks like itself after a month. Growth is what happens during wear, as the knee, elbow, seat and cuff extend under load and hold part of that extension. Recovery is how much comes back when the load is removed. Shrinkage is what the wash does, as the yarn releases tension put into it during knitting and the fabric settles shorter, wider or narrower than it left the factory.

Some effects belong to specific structures. A wool fabric can felt, thickening and contracting as the fibre scales lock together under heat and agitation. A single jersey knitted in the round can develop spirality, where the twist in the yarn works against the fabric in washing and walks the side seam around the body. Neither is visible in a fibre content statement. Both are visible in a washed sample.

None of it follows from the fibre name, because the same yarn behaves differently at different tensions. Knitted slack it makes a fabric that grows and does not come back; knitted tight it recovers and feels board-like. Tension, gauge and the finishing route decide the answer together, which is why the test runs on the actual fabric.

The test itself is cheap. Mark a measured area on the fabric or the garment, wash and dry it to the care instruction that will be printed, then measure the same marks again, and repeat for several cycles because the first wash is not the whole answer. For extension, load a marked area to a set force for a set time, release it, and measure again after a stated recovery period. Then write the care instruction to match what was tested, and build the numbers into the pattern or the programme, so a fabric known to contract in length is made longer.

09Colour commits at the yarn or at the cloth

A knitted product takes its colour at one of two moments, and the choice governs the lead time and how late a colourway can be added. Dyeing the yarn fixes colour before knitting begins. Pre-coloured yarn is the usual route for contrasting stripes, jacquard, intarsia, tipped trims and marl. Fibre-dyed or differently dyeable yarns offer other routes; confirm the method with the knitter and dyer. The commitment therefore sits early, and a colourway added afterwards starts a new lot with its own dyeing and delivery time in front of it.

Piece dyeing and garment dyeing invert that. The cloth or the finished garment is made undyed and coloured afterwards, which moves the colour decision much later and allows undyed stock to be held and dyed against real demand. The trade is that the result is a solid colour, the sewing threads and trims have to be chosen either to take the same dye or to sit in deliberate contrast, and shade varies between lots more than it does with dyed yarn. Dimensional change is largely set in that same operation, which is why final approval for a garment-dyed style is based on measurements and tests after dyeing. Before-and-after measurements establish the required allowances.

The route also changes the shape of what is being committed to. On cut-and-sew the commitment tends to attach to cloth: a colour is a dye lot, and every style cut from that lot draws on it, so five jersey styles in one colour are a single material decision. On fully fashioned it tends to attach to the yarn and its colour, and every style and every size knitted from that yarn draws on the same purchase. Minimums themselves are set per style and confirmed at enquiry.

10Prove the fabric with a knit-down before a sample exists

A knit-down is a piece of fabric knitted in the intended yarn, at the intended gauge, in the intended structure, on the machine that will make the garment. It is the cheapest and fastest decision point in knitwear development, and it settles most of what a first sample would otherwise be asked to settle. On cut-and-sew the equivalent is a length of the development cloth, finished the way production will finish it.

Handle and weight

How the fabric feels against skin, how heavy it is per square metre, and whether that weight matches the season and the retail position the range is aiming at.

Stitch definition

Whether the structure reads at this gauge in this yarn. A cable, a rib or a pointelle either resolves into a legible feature at full scale or it does not.

Dimensional behaviour

How far the fabric moves through a wash cycle, in which direction, and whether it settles after the first cycle or keeps moving through several.

Recovery

How the fabric responds to being loaded and released, which decides whether ribs hold, whether knees bag, and how the garment looks by the end of a day.

Colour in fabric

How the shade reads in a knitted structure under real light. A colour approved on a card or a wound cone reads differently once loops start creating shadow.

Surface durability

Whether surface fibres migrate and pill under rubbing, which is a property of the spin and the twist and shows up long before a garment exists.

Sequence matters as much as the test. The knit-down comes before pattern work and before the programme is written, because weight, thickness and dimensional behaviour all feed the pattern and the stitch counts. Review the piece in the state a customer will meet it, which means washed and finished, not straight off the machine where the fabric is still tight and the stitch has not yet opened.

A knit-down does not answer everything. Fit, proportion, make-up quality and how the trims sit against the body all wait for a garment. The first sample is never the product describes what that first garment is for. The point of the knit-down is to arrive at it with the material questions already closed.

11Choose the route from what the first range has to prove

The route follows the argument the product is making. When the idea lives in the graphic, the fit, the colour or the brand around the garment, cut-and-sew jersey carries it. One cloth serves several styles, colour can commit late if the cloth is piece dyed, patterns are quick to revise, and a second version of a style is a pattern change and not a new programme. That combination lets a first range put a proposition in front of customers and react to what comes back.

When the idea is the knit itself, cut-and-sew cannot make the argument. A structure that only exists at a particular gauge, a shoulder that only sits correctly when it is knitted to shape, a yarn whose handle is the reason anyone would want the product: these need the fully fashioned route, and the calendar starts earlier, because yarn dyeing and programme development both sit in front of the first garment.

Mixed ranges work when each route has been given a job. A common shape is jersey carrying the volume and a small number of fully fashioned pieces carrying the signature, with a shared palette so the two sit together on a rail and in a photograph. A range that arrived at both routes by accident doubles the development, doubles the supplier conversation, and asks a first season to prove two unrelated things at once. What a first collection has to prove is the test to hold each piece against, and Planning a first range covers the range structure once the route is known.