Is there such a thing as correct yarn directionality? Does it change with knitting versus crochet? Are some affected by it and some not?

Technical Understanding of Yarn Directionality

One of the questions I got in comments the other day has me thinking:

“Something that I’ve been wondering about as I deal with splitting yarn, is this:
Several years ago, and in different context, I was told that yarn structure had (for lack of a better word) direction. That to manipulate it from one end vs the other yielded a different ‘product’. Whether or not it was true then, would an evaluation today, with the proliferation of natural and synthetic fibers and manufacturing processes used today or whether it’s being used right or left-handed, and with your experience, be different?“

Judy in comments August 28, 2023

First of all, splitting yarn can have multiple structural causes. In my experience, it’s rarely the directionality of the yarn that causes it.

Ted Myatt was one of the more technically-oriented spinners I know. He used to mark his hanks of yarn with the end of the yarn you should start with. He said his handspun had a nap to it that made it easier to use it in the direction of the nap. But I’m pretty sure the nap didn’t affect whether the yarn was more easily splittable.

The other thing that more often affects how loose and thus splittable a yarn can be is the direction of the plying. Most yarns have singles that are spun in one direction (s-twist or z-twist) and then plied in the opposite direction. As you use yarn in your knitting or crochet, there are certain movements that will loosen the twist and/or tighten the twist.

For instance, when I do a standard long-tail cast-on with most commercially spun knitting yarns, the change in twist is most noticeable. The tail-end of the yarn gets looser and looser (unplied) as I cast on more and more stitches. And the ball-end of the yarn gets tighter and tighter (more tightly plied). When I’m casting on 50 or more stitches, I’ll often have to let the tail-end re-ply itself by letting it hang.

If the nap of your yarn is really the issue, there is only one resource that I found that might help – https://www.heartstringsfiberarts.com/yarn-direction.shtm

If tightening and loosening ply is your issue, then I found this article to be comprehensive – https://www.schoolofsweetgeorgia.com/twist-and-shout-why-twist-direction-matters-in-your-making/

Current Crochet

Good news and bad news. Good news is that I finished the body of the short-sleeve, crochet shirt and sewed up the shoulder seams.

Bad news is that I need more girth on the body of the shirt. I’m adding a faux button band to add a few inches of width to the garment.

Hopefully that will fix it. But if not, it was a fun design experiment that someone more slim might get to enjoy instead of me.