On a cold morning, you pull on a sweater without a second thought. But how does yarn become sleeves, a neckline and a body that fits? Making one from yarn is another story.
Machine knitting has a long history. In 1589, William Lee developed the stocking frame, the first mechanical knitting machine. Today, some industrial machines produce lengths of knitted fabric, others knit garment pieces to shape, and specialized machines can knit an entire garment in one piece.
So how do these machines differ? Let’s look at the main types, how each one works and which type may be right for your product.
Types of Industrial Knitting Machines
Industrial knitting machines can first be divided into two broad groups: weft-knitting machines and warp-knitting machines.
Circular and flat-bed machines are common types of weft-knitting equipment. Tricot and Raschel machines belong to warp knitting.
| Machine type | Typical output | What it may become |
|---|---|---|
| Circular weft-knitting machine | Tubular or continuous knitted fabric | Fabric cut and sewn into a T-shirt |
| Flat-bed weft-knitting machine | Flat fabric or shaped panels | Panels joined to make a sweater |
| Tricot or Raschel warp-knitting machine | Warp-knitted fabric | Apparel fabric, lace or mesh, depending on the machine |
How Do Knitting Machines Work?
All knitting machines make fabric by drawing new yarn loops through existing loops. Repeating this action produces connected rows and columns of stitches.
The machines differ in the way yarn reaches the needles, how the needles are arranged and how the newly formed fabric moves away from the knitting area. These differences determine whether the machine normally produces a tube of fabric, a flat panel, a shaped garment piece or another type of knitted material.
Circular Knitting Machines
On a circular knitting machine, needles are arranged around a cylinder. As the needles form successive rows of loops, the knitted fabric commonly comes out as a continuous tube.
The needle arrangement affects what the machine can produce. A single-knit circular machine uses one main set of needles and can make fabrics such as single jersey. A double-knit machine uses needles in both a cylinder and a dial, allowing it to produce structures such as rib and interlock.
For conventional fabric production, the tube is removed from the machine and sent through the required finishing processes. Depending on the garment design, it may remain tubular or be opened into a flat width. Pattern pieces are then cut from the fabric and sewn together.
This production route is widely used for T-shirts and other cut-and-sew garments.
Seamless Circular Knitting
Seamless circular knitting follows a different production route. Specialized machines use smaller, garment-sized cylinders to knit tubes closer to the dimensions of the final product.
For example, the body of a top can be knitted without side seams. Stitch structures may also be positioned in different areas to create ventilation, support or stretch zones. This technique is often known as body mapping and is commonly used in products such as activewear, underwear and hosiery.
The word seamless does not always mean that the complete garment leaves the machine ready to wear. Armholes or neck openings may still need to be cut, edges may need finishing, and additional parts may need to be attached. Some circular systems also produce garment sections in a continuous tube that must later be separated and assembled.
Flat Knitting Machines
A flat knitting machine has needles arranged across a straight bed. Many industrial models have two beds facing each other in an inverted V shape, which is why they are often called V-bed machines.
A carriage travels back and forth across the beds. On each pass, it feeds yarn to selected needles and adds another row of knitting.
Flat machines can produce structures and patterns such as jersey, rib, cables, jacquard and intarsia. The available options depend on the machine, its needle arrangement and its programming capabilities.
Flat knitting is particularly important in sweater production because a suitable machine can change the width and shape of a piece while knitting it.
A sweater front, for example, can be narrowed toward the shoulders. A sleeve can gradually widen from the cuff to the armhole. The machine produces the required outline by adding, removing or transferring stitches instead of knitting one large sheet and cutting the shape from it.
This production method is known as fully-fashioned knitting. The front, back and sleeves are knitted as separate shaped panels. After knitting, their edges are joined—often through a process called linking—before the garment is washed, finished and inspected.
Whole-Garment Flat Knitting
Specialized computerized flat machines can take this process further by knitting the body and sleeves as a connected garment.
This reduces much of the joining required for separate panels. However, the exact result depends on the equipment and the design. Some garments may still require finishing or partial stitching after knitting.
Not every flat machine can make an integrated garment. Fully-fashioned panel knitting and whole-garment knitting are therefore two different production routes, even though both can use flat-bed technology.
Warp Knitting Machines
Warp knitting works differently from circular and flat weft knitting. It uses many yarns running lengthwise through the machine. Guide bars position those yarns around the needles and shift them between neighbouring needle positions, connecting the loops into fabric.
Two important types of warp-knitting equipment are Tricot machines and Raschel machines.
Tricot machines are commonly associated with relatively fine, smooth fabrics. They can be used for products such as lingerie, sportswear linings and other lightweight knitted materials.
Raschel machines can produce more open or decorative structures. Common examples include lace, mesh and netting. Depending on the machine configuration, Raschel technology can also be used for spacer fabrics and technical textiles.
Unlike fully-fashioned sweater production, warp knitting normally produces a length of fabric rather than separate body and sleeve panels. That fabric is subsequently finished, cut and assembled according to the intended product.
What Do Fully Fashioned, Seamless and Whole-Garment Mean?
These terms describe different aspects of garment construction.
Fully fashioned
Fully fashioned means that separate garment pieces are shaped while they are being knitted.
A sweater’s front, back and sleeves can be knitted to their planned outlines. The pieces still need to be joined before they become a complete garment.
Seamless
Seamless describes the removal of particular seams, but it does not explain the entire production process.
For example, the body of a circular-knitted top may have no side seams because it is produced as a tube. The neckline, armholes or other parts may still require cutting, joining or finishing.
When a supplier describes a product as seamless, the practical question is: Which seams have been removed?
Whole-garment knitting
Whole-garment knitting uses a suitable specialized flat machine to knit the body, sleeves and other sections as a connected garment instead of separate panels.
This can substantially reduce later assembly. Finishing—and, for some designs, partial stitching—may still be necessary.
These construction descriptions can sometimes overlap. The clearest way to distinguish them is to look at the actual machine output:
- Fully fashioned: separate shaped panels
- Circular seamless: a garment-sized tube or tubular garment section
- Whole-garment knitting: a more complete connected garment
WHOLEGARMENT® is a registered term for SHIMA SEIKI’s designated knitting technology. It should not be used as a general name for every garment made with fewer seams.
Which Knitting Machine Is Right for Your Product?
Begin with the product rather than a machine name. Bring a sketch, tech pack or reference sample to the factory and define three things:
- The fabric you want
- The shape of the finished product
- Where seams can or cannot appear
These details help identify a suitable production route.
If the garment will be made from cut fabric pieces, discuss machinery that produces continuous fabric. The resulting fabric should be compared with your reference for structure, weight, stretch, appearance and hand feel.
If you are developing a sweater with shaped sleeves, armholes or a neckline, discuss flat knitting. Decide whether the design should be produced as separate fully-fashioned panels or assessed for a more integrated construction.
If the design requires fewer seams, identify exactly which seams you want to remove. A circular machine that produces a seamless body tube and a flat machine that produces a connected garment solve different construction problems.
Once the general route has been identified, check whether the proposed machine is suitable for:
- The intended yarn
- The required structures and patterns
- The finished measurements and size range
- The necessary knitting width or cylinder diameter
- The required shaping
- The planned cutting, linking, sewing and finishing
For flat-knitted sweaters, machine gauge is another important consideration. A coarser gauge has fewer needles per inch and generally works with thicker yarns and larger, more visible stitches. A finer gauge places more needles within the same distance and typically works with finer yarns to create smaller stitches and a smoother surface.
Gauge alone does not determine how the finished fabric will look or feel. Yarn, stitch structure, loop length and finishing also influence its weight, texture and drape.
The final decision should be based on a sample made with the intended yarn and construction. Review the sample after its planned washing and finishing processes, checking its measurements, appearance, fit, stretch, seam placement and overall hand feel.
Fully Fashioned Knitting with GUOOU FASHION
GUOOU FASHION helps brands turn sketches, tech packs and reference samples into knitwear samples. During development, we work through the yarn, stitch structure, gauge, shaping, measurements and fit. For suitable projects, we can also assess seamless garment options.
Developing a knitwear style or collection? Contact GUOOU FASHION with your design brief or reference sample to discuss the construction and sampling options for your project.
