The Over & Under of Cloth Analysis
Inspiration for handwoven designs are everywhere.
If you have ever admired the cloth design of a pillow, placemat, old garment, or fabric store find, and wondered how it was woven, you can discover the structure and loom requirements for it using cloth analysis.
A few tools are necessary, along with a willingness to unweave your sample fabric "for the greater good." This procedure is not recommended for old or cherished textiles. Although with experience, you may be able to recognize the structure of delicate items without invasive observation.
Some of my favorite sources for handwoven design inspirations are the household linens sold at Pier 1 Imports, World Market, and Crate and Barrel.
This sample cloth I analyzed for this article is a find from a much-loved local mega-store: Mary Jo's Cloth Store. The cloth is drapey, garment weight, and the subtle differences in the two golden colors against black are reminiscent of an organic leopard-skin pattern.
Equipment and Supplies
- Graph paper to chart the cloth design.
- A "pick glass" (also called a linen tester or loupe) with magnification 5X or higher.
- An awl, scriber, or large tapestry/needlepoint needle to gently move yarns within the cloth structure
To begin, determine the direction of warp versus weft
If your sample has no obvious selvedge to indicate how it is woven, one way to determine the orientation is to compare the "give" in opposing directions.
Grasp the cloth with your thumbs 2 to 3 inches apart and try to tug it apart firmly. Do this in each direction, paying attention to which direction allows the most, or easiest, movement between your fingers. The direction having the most "give" is the weft direction.
This is because warp yarns of industrially-woven cloth are typcially stronger than the weft yarns, with higher twist, synthetic fibers, and/or applied sizing to help withstand the rigors of high-speed weaving. Thus the warp yarns will not stretch as readily as the weft yarns.
Next, find the epi and ppi. This step is important for finding the ratio between the warp and filling systems, which maintains the pattern scale.
A pick glass (or linen tester) is designed so that when it is opened and placed on a surface, the magnifying lens is the proper distance from the object being examined. They are available from graphic arts supply stores, and also are carried by Halcyon Yarn. A good source of light facing you from the front will help eliminate shadows in the close-up view, especially if it is capable of aiming at a low angle, like an adjustable desk light or Ott Light.
Pull yarns from two adjacent sides of your cloth to create a fringe. Measure the yarns-per-inch by using the glass to frame-off a one inch area at the edge where the fringe meets the woven section, and count the yarns that are visible within the one-inch square opening. In commercially woven cloth, the number of warps per inch will almost always be greater than the number of wefts per inch.
So, if your perception of the "give" mentioned above seemed ambiguous, then another clue to which yarns are warp is to find which direction has more yarns per inch.) My sample has 26 warp yarns per inch, and 22 wefts per inch. (Note: In actuality, this cloth utilizes pairs of yarns that weave together in both warp and filling directions, making the actual totals 52 ends per inch by 44 picks per inch. I am considering each pair as a single yarn for simplicity.)
As you pull out yarns to make the fringes, make a note of the order (or rotation) of differences in color and/or style if they exist.
For my sample, both the warp and weft yarns follow a pattern of four light gold, four black, four dark gold, and four black repeating throughout.
Besides color, yarns may differ in size or type, such as thick vs. thin, straight vs. fuzzy, etc.
Now you are ready for detective work!
One mystical quality of woven cloth is the deceptive simplicity underlying the most intricate structures and patterns. Very simply, each individual yarn from one direction interacts with each individual from the adjacent direction. The sum of yarn intersections in a cloth is the total number of warps multiplied by the total number of wefts—a number that can become very high very fast. Yet, for any yarn intersection within the cloth, only one of two possibilities will ever occur—either the warp will rise on top of the weft, or it will sink below it. (Conversely, from the perspective of weft, either the weft will be under the warp, or else it will float above it.)
That's it! Only two possibilities, no matter how you describe it! To make the cloth structurally stable, however, both possibilities must exist in opposition of each other. The positive and negative, yin and yang, work together to define and compliment each other, creating a functional and harmonious whole. The nearly infinite possibility of positions for all yarn intersections determines whether the cloth will be a simple two-harness plain weave, or one that requires the individual yarn control of a jacquard machine, as well as anything in between.
With your sample oriented as it was woven (i.e. warp running "north and south" and weft running "east and west") gently tease the first warp yarn out into the "eastern" fringe of weft yarns without displacing its position among them. (Left-handers may be more comfortable working from the "west" side of a swatch, which is perfectly fine.)
Use a slender, pointed tool such as a large T-pin, tapestry needle, or scratch-awl for the yarn manipulation. My tool is marketed by General Hardware as a "scriber", though I refer to it as a "pick needle." (Note: When not in use, the pointed end can be removed and reversed into the casing for protection of both tool and user!)
Position your pick glass near the "north-south" fell line, so that the close-up view allows you to see the proper order of the picks making up the fringe, as well as the warp that you pulled away for examination. Beginning with the bottom pick, simply follow the path of the warp yarn upward, by moving each weft slightly to observe its position relative to the warp yarn.
Download larger image
Record on graph paper whether the warp yarn lies above or below each successive pick. Use an "x" (or fill in the rectangle) when the warp yarn is on top of a pick, and a small dot when the warp lies below a pick. (You can also leave the square empty to show the warp sinking below the weft, but using a tiny dot helps to keep your place in the analysis.)
Continue recording the path of the warp yarn through the wefts until you notice a repeating pattern, then remove the yarn completely from the sample.
Do the same analysis for each successive warp, recording them from right to left on the grid paper, just as they are positioned in the sample. (If you are working from the "western" edge of the sample, you will record the warps from left to right on the paper.) Differences in the color or style of yarns may be recorded to the side for weft and at the top or bottom of your work for warp. When the number of picks in a vertical repeat is confirmed for a few successive warps, then for the remaining warp yarns, you need only to count and record the warp positions for that number of picks.
Notice that my first warps on the far right were recorded for more picks in the vertical direction. After examination of a few more warps, I felt safe that the vertical repeat for this cloth occurs on 16 total picks, so that was all I needed to record for the subsequent yarns.
To find the horizontal repeat of the design, make sure that you have accounted for all warps in the color or style rotation of the yarns along with the woven repeat. For example, plain weave repeats on only two warps and two picks, but if a stripe pattern is designed into the warp and/or weft, then the full design repeat will include the color information as well and be much larger than two picks.
You now have a cloth diagram, or drawdown, of your sample, It is not important whether this initial diagram is "centered" properly in either direction, but only that it is entire and complete. Once you know the full pattern repeat in each direction, you may center it to your liking by "wrapping" the columns (for ends) from one side to another, or the rows (for picks) from top or bottom as needed. My example repeats on 16 ends and 16 picks, and the photo above shows one repeat in each direction highlighted in yellow.
Now to figure out the number of harnesses used to weave the cloth pattern. The mantra here is simple: Ends that weave alike are threaded on the same harness.
Beginning with the first warp on the left of your drawdown, assign it to harness 1. Moving from left to right, check the path that each warp takes relative to the ones before it. Each successive warp will be assigned to the next available harness, but only if it weaves differently from the ones before it. When any warp in the diagram weaves the exact same pattern as any other one, then it will be assigned to the same harness.
For my sample, the first end is assigned to harness 1, the second one to harness 2, the third one to harness 1 again, and the fourth end to harness 2 again and so on.
Continue this sequential assignment of the ends in the cloth diagram to separate harnesses for the entire repeat, duplicating when necessary. In the end, my sample requires eight harnesses for the threading.
To determine treadle tie-ups, simply examine each row of the pattern (in the pick-wise direction) and record all harnesses that will be raised for that pick. In my example, the first pick weaves under the ends on harnesses 1, 3, 4 and 7, so that determines the first treadle's tie up. The next pick weaves under warps on harnesses 2, 3, 4, and 8, so that requires a second treadle. Continue assigning treadles in the same sequential method as used for harnesses, and any treadles used more than once will show as a repeat in the treadling sequence.
Assign the treadles
If you have weaving software, you can transfer the weave draft to your computer.
Now that you have discovered how your sample was created, you have all the info needed to vary the structure to your own preference of yarn size, color and texture. If you don't have enough harnesses, it is often possible to adapt a structure to what you do have, albeit with alterations.
Learning to reveal how a fabric is made is another tool for designing your own creations. Textiles will no longer be seen as merely decorative or functional, but subject to study and interpretation.
Note: Please remember that any cloth design is intellectual property owned by an individual or a company. The intent should never be to create an exact copy of a cloth that someone else has spent their time on. This is especially true if the "borrower" intends to offer the cloth design in items for sale. Cloth analysis as a skill should lead to new ideas rather than repeating old ones.
Annette Norviel works in North Carolina as a textile designer for residential and contract upholstery fabrics. She enjoys trying her hand at gardening, and fostering a role as the "crazy squirrel lady" of her neighborhood. (No real animals were taken hostage for this photo.)
Photo Credit: Some photos taken, and much computer help provided by William Mann (husband)