The thickness of two yarns can be very similar, but they can still be different because of twist. Twist refers to the spiral configuration that contributes to the cohesion of the spun yarn. In particular, beginners may pay attention to thickness and fail to notice the degree of twisting. The following is a method for easily recognizing the difference in twist.
Prepare two yarns of approximately the same thickness and lay them on a flat surface with adequate lighting. Hold each yarn with your fingers and turn it slowly, observing the spiral pattern on the surface of the yarn. One yarn will appear dense while the other appears fluffy. A magnifying glass will help you determine the spiral angle, especially if the surface is fuzzy.
However, twist is not just a matter of visual effect. It affects how cohesive the yarn is, its elasticity, and its surface condition. But twist is not necessarily a sign of quality. More twist does not necessarily mean better quality. It must be considered in conjunction with factors such as the type of fiber, yarn count, the number of plies, the structure of the fabric to be made, and the finishing process.
To compare the two yarns, first check the yarn itself before checking the fabric. Which one is more compact? Which one has more loose fibers on the surface? Is the thickness constant throughout the yarn? Bend the two yarns slightly instead of stretching them hard. You can also differentiate by bending them gently without making it a strength test.
Sometimes beginners will think that any spiral is the same thing as twist. Slow down and observe the spiral pattern over several centimeters. Twist is a repeated spiral pattern of fibers around the yarn axis. For a plied yarn, observe the individual twist of each individual strand and then the twist of the yarn around the plied strand.
After checking the yarn, check a fabric swatch containing a similar yarn. Observe whether the yarn surface of the fabric makes a contribution to the fabric texture. You should not assume that the fabric properties can be explained by twist alone. The yarn construction becomes only one aspect of the system, along with the relationship between warp and weft yarns, the loops of the knitted fabric, fabric density, and finishing.
If you are getting better at recognizing twist, you should no longer write simply thick or thin or smooth in your notes. If you can distinguish and write about the twist, the loose fibers, the evenness, and the ply, you are beginning to read the yarn as a component of a textile system.
