Three Dimensions

One thing I love about knitting is that it can be three-dimensional.

Sample E, unfolded

Knitting doesn't have to be. Making a scarf or blanket is usually a two-dimensional process. It is creating a flat plane of fabric. Sometimes there are texture patterns, but we think of them as embellishments or decorations. We think they aren't fundamentally changing the nature of the item as a plane.

Socks are a great example of three-dimensional knitting. They are typically worked in the round. They have special shaping to turn the heel. If they are knee socks, they might even having shaping through the calves. And, of course, there is shaping at the toes. Think about all the socks you own. Are any of them made from flat fabric sewn together? Even commercial socks are typically worked in the round with a seam at the toe.

While I find weaving intriguing for its mathematically properties, loom weaving is a two-dimensional technique. Fabric on a loom is a plane. You make it fit a human form in three dimensions through cuts, folds, pleats, darts, gathers, and seams.

I was particularly delighted a few months ago to see this technical work about knitting and how it naturally wants to fold. Anybody who has fought curling stockinette knows knit fabric can seem to have its own opinions about what it wants to be. Sometimes blocking will encourage a fabric to behave as we wish — temporarily. In ideal design circumstances, the knitter creates a fabric where the final form and the form the fabric intrinsically wants to take are congruent.

If you want to observe the true nature of your chosen pattern in full force, swatch with inexpensive worsted-weight acrylic. Acrylic does not relax and block in water, as wool does. Wool is forgiving, in that you can sometimes block it to a shape that is not entirely congruent with its nature. Acrylic will not do that unless you "kill" it — melt it by hitting it with steam. The downside of killing acrylic is the fabric now has drape but no elasticity. If you've never experienced this, make two swatches, "kill" one, and see how very differently the fabric behaves.

Part of what I found intriguing about this paper is how knit-purl patterns cause the fabric plane to deform. As knitters we think about knits and purls as decoration. We think of increases and decreases as ways to shape fabric. But in this paper, the pattern of knits and purls is what shapes the fabric. Pattern is more than mere decoration. Knit-purl patterns can be a way to program buckling into a fabric.

Sample E, folded

If you scroll down in the paper, you'll see Figure 3 with an assortment of seven fabrics that exhibit intriguing folding properties. I haven't knit all seven. I did knit sample E, which has a fascinating accordion-like property. The paper didn't provide charts for the samples, but I was able more or less to reverse-engineer the patterns by scrutinizing Figure 3. Below is my chart for sample E.

If you want to work from this chart, blue is a purl, red is a knit.
The black box is one pattern — multiple of 20 + 2 with a 12 row repeat.
The dark columns on the left are there to balance the motif. They are the +2 part of the multiple.
You can also break the pattern at the two wales of knit stitches. In my swatch, I broke the pattern in the middle of a block rather than on a fold line.

I'm not yet sure what I might do with such a technique? This particular pattern suggests it is possible to create a self-folding blanket. On the other hand, this information also suggests some knit-purl patterns by their very nature will resist lying flat. In a blanket on a bed this may not matter, as once the fabric is laid on the bed it might not be able to work against gravity. But for something that hangs freely like a scarf, some knit-purl patterns will contort in ways that may or may not be desirable. This also makes me wonder if it is possible to knit an origami pattern so the final piece of fabric will intrinsically want to fold up into a crane or frog?