Almost every yarn has twist (among the few that don’t are flat yarns like ribbon, reed, and metallics). Twist is what makes natural fibers hold together as yarn. It’s what makes the plies of thread hug together in a strong yarn. Even man-made fibers benefit from the twist. This post talks about slightly adding or subtracting twist by which end of a spool you take the yarn off of. These situations aren’t common, but may occur with over-twisted, unbalanced, or single ply yarns.
Three major truths about twist to keep in mind:
1. In general, adding twist makes a harder, stronger yarn.
2. In general, subtracting twist makes a softer, more easily abraded yarn.
3. Twist has two directions: S twist and Z twist.
You can add S or Z twist when you unwind yarn from the end of a spool.
When the yarn, as seen from the end of the spool, moves in a counter-clockwise direction as it unwinds from the spool, S twist is added.
By turning the spool end-for-end, the yarn will move in a clockwise direction as it unwinds, adding Z twist to it.
Repeating the principle: which end of the yarn package the yarn comes off from dictates the direction of the twist put into the yarn—because the yarn is coming off the end.
You can add or subtract twist not only by how you wind a pirn, but also by which end of the spool of yarn you take the yarn off of. Now, every time you wind or unwind yarn, you can slightly add twist, subtract it, or have no effect on it.
How you unwind a ball of yarn determines the amount of twist as well as the direction of twist. If the ball rolls around and the yarn comes off the side, you know that no twist is being added.
If the yarn comes out from the center and off the top of a ball a small amount of twist is added or subtracted depending upon which end of the ball is on top as usual.
If you unwind the ball starting at the outside of the ball, the amount of twist being added (or subtracted) increases as the circumference of the ball gets smaller and smaller. However, if you begin to unwind a ball from the center of the ball where the circumference is small, you’ll be putting in the most twist at the beginning. It will gradually get less and less as the circumference of the inside of the ball gets bigger as it is unwound, because one twist is added for each time the yarn traverses the circumference of the ball, making more twists per inch where the circumference is small—in the center. If this is a problem (kinks in the yarn) let the balls roll around on the floor as you wind. Then any twist will work itself out before it gets to the winder.
You can always check yourself with a roll of toilet paper so you don’t need to worry if you forget all of this!