Defining the Product
Patterned knits are created based on carefully thought-out technical design plans. A specialized form of knit, referred to as jacquard, can be produced when needles are manipulated independently as yarn and color are introduced.
Fabricated on machines set up for a single or a double set of needles this form of knit affords designers the freedom to create complex patterns and intricate motifs.
During the planning phase, artistic talents merge with technical knowledge of how machines actually knit. Before imagination takes hold questions that influence the design and use are asked first:
- What is the target market for this product and application?
- Will the fabric be used for outerwear? Intimate apparel? Sports or casualwear?
- Will the garment be worn by women, men, juniors, or children?
- What kind of motifs might be appropriate for the audience and end-use?
Once the desired outcome has been identified, plans can begin for how the fabric will be produced.
Considerations in Planning
The first thing to consider is construction. How does the fabric need to be structured to perform well and present the right look? Does it need to be stable or stretch? Should it have texture or be smooth?
The second factor to consider is the content of the fabric and what combinations of yarn or fiber types might be used to alter performance or effect. For instance, you can produce exercise garments requiring a fabric that can have more stretch and better recovery by adding 5% spandex to a fabric that is initially 100% cotton. Different colored yarns or fibers can be combined to produce design and color effects.
The third factor influencing design is how color is used. Once the basic pattern is established the colors of the basic fabric can be altered. You can begin with fabric knit using yarns that have been dyed in different colors to create a pattern design. Or you can take a fabric knit with all-natural cotton yarns and piece dye it to achieve whatever effect you want. Or you can create a design by knitting with two colors, for instance using natural and black yarns and then overdyed to a particular pastel or medium color requested by the customer. With this method, variations of different shades and color schemes can be easily produced. We mentioned that the fiber content of the yarns can be chosen to affect color because different fibers react differently to dyes there are variations you can intentionally produce. Fabrics made up of different fibers can be cross-dyed so that each fiber becomes a different color. One dye is selected to color the cotton fiber, another dye is selected to color the second type of fiber. The advantage to this approach—one fabric created from two different yarns can be kept in inventory and later be dyed to many different color effects.
Another approach, union dye, refers to a technique used to dye two fibers the same color using two different dyes. Here, two different fibers were dyed the same shade to achieve the appearance of a solid-colored fabric which takes advantage of the physical and aesthetic characteristics of each fiber. In addition to dyeing applications, yarns can be combined for special effects. You can introduce texture and interest by incorporating novelty yarns such as boucle, textured yarns with nubs or slubs, The content of the yarn, the size of the yarn, and the appearance of the yarn all play a part in how the structure will look. The size of the yarns in the mix you have selected makes a big difference in what machines can be used to produce the fabric.
Once all the decisions have been made about fabric construction, the content of fibers, and the colors, attention turns to the knitting machines available for use. Which machines have the capabilities needed to fulfill performance requirements?
After the knitting machine has been selected and the pattern capability is known, a designer turns their attention to the technical design. The designer gets started by deciding how large the canvas should be, the size of the pattern area is determined by the number of courses and wales that will conscribe and contain the pattern.
Then comes the creative part of the design. Ideas for a motif can come from anywhere, like a natural object, like a feather, shell, or leaf. Patterns abound in fine and applied arts. Paintings, sculpture, textiles, and other mediums can be a source of inspiration and motivate the styles of representation. In some cases, the designer may begin with a scanned image and then isolate and rearrange parts.
Digital imagery enables designers to modify and generate original patterns. Using computer-aided design, a designer may change or reduce the number of colors. As images are repositioned or changed in size, the pixels or small dots representing color on a computer screen can become fuzzy or jagged. Careful attention to process is required to clean up the design.
Once the design is crisp, the designer produces a variety of pattern repeats to create the composition of the final design. Patterns can be replicated side-by-side, half drop, staggered, or tiled. The motif can be sized, flipped, mirrored, or rotated. Parts of the picture can be filled with different colors to compliment the overall design.
Once the final pattern is selected, the designer instructs the computer application to convert it into a technical design. The computer determines what needs to happen at every feed with every needle. Colors seen on the screen, real colors, are converted to system colors which are later translated to instructions understood by a knitting machine.
At this point, a designer must shift from aesthetics to technical concerns and take into account what format is used on the machine dedicated to knit the fabric. Is the knitting machine mechanical or is it an electronic machine? The layout of the pattern is affected by what type machine is used. The designer indicates which knitting machine will be used and based on its type, the designer inputs the number of feeds, the number of needles used, and what yarn is assigned to which feed. The designer compares the intended design with what can be produced based on the capabilities of the knitting machine. For instance, a two-color pattern planned for a single knit must be expanded because there is the option to knit, tuck or float at each feed.
When the designer is confident that desired results can be achieved, the designer instructs the computer application to translate the design information into a language that can be interpreted by a particular knitting machine. If the machine is mechanical, driven by a drum, a pattern wheel, or step jacks, the instructions relevant to a particular machine are detailed in a printout. These printed reports specify technical information such as how to peg drums, how to slot wheels, or what step jack selection applies to a particular machine. If the knitting machine is electronic and equipped with a controller, instructions can be saved to a disk and loaded directly into the machine. In some manufacturing settings, instructions can be routed from the designer’s computer to the knitting machine on the factory floor.
The final design motif is transferred from the studio on paper or disk to the factory floor where fabric construction begins. If the knitting machine is electronically controlled, the instructions needed to interpret a pattern are loaded into the machine. If the knitting machine is mechanical, technicians examine the printout to note specifics on setting drums, wheels, or selection devices.
Regardless of the machine, yarns must be placed in the proper sequence on the creel. Here you see how yarn positioned to knit a two-color jacquard pattern is set up so one color knits on even feeds of yarn and the other knits on odd feeds. To ensure the machine properly knits all technical information must be correct. Also set is the length of the stitch. Stitch adjustments can be made to change the width, weight, and hand of the fabric. Stitch length affects how the pattern will be seen. Smaller stitches create a tighter, smaller pattern than stitches of longer length.
Once instructions have been loaded or followed and all functions are set, it’s time for a trial run. First, the machine is jogged so that it moves slowly. Then the first course of knit is examined to see if the needles are doing what is expected. If everything is operating properly, then the decision is made to increase to full knitting speed.
When a representative sample has been successfully produced, the machine gate is opened and a portion of the fabric is snipped off. Technical diagrams, graphs, and printouts of the pattern are compared to the knit fabric to make sure the pattern is accurately represented and knit correctly. Problems can occur if yarn is out of place, if needles have not been properly selected, or if there are pattern mistakes.
If the pattern meets design expectations, the decision is made to move forward. Before going to full production, technicians complete a spec sheet detailing information about the type of machine, the correct settings, the type of yarns used, as well as the weight and width of the fabric. Also noted are course length, stitch length, and machine speed.
To visualize how the finished product will appear in garment form, it’s back to the studio to evaluate results. A designer might select a picture from a magazine or a stock photo appropriate to the application of the fabric. The designer can either import the design into the application or scan the fabric itself. Next, the design planned earlier is scaled and texture-mapped so it fits the garment worn by the model and the final effect is reviewed.
You’ve seen how construction can vary and design can be enhanced easily using knitted fabric. Because it is so convenient to manipulate needles and the resulting structure, knits can quickly be brought to market.
Artwork Files for Knitwear Design
In this webinar, Alexis Mondragon—technical designer, knitwear specialist, and sweater consultant for Cotton Incorporated—takes a deeper look at:
- Artwork and body mapping solutions using Adobe Photoshop
- How to format artwork files that are compatible with flat bed and circular knitting machines
- Knitwear design utilizing Cotton Incorporated’s FABRICAST™ collection