How does it happen that the yarn in the ball is broken or what causes it to repeatedly break while working?
Damage, such as cut or broken yarn, is not caused until after the ball winding process is completed. During the winding of the ball, the yarn must be under tension. Since a yarn which is not under tension can't be wound, the winding machine stops immediately if the yarn breaks or ends. In individual cases, the yarn itself may be faulty but in most cases, such damage is due to external influences, such as pest infestation, which occur after the ball has been removed from its sealed plastic packaging. Textiles in human habitation throughout the world are subject to damage by clothes moths. This type of moth is active throughout the year and favors living and storage spaces. For their development, the tiny larvae of the clothes moth need keratin, a protein component of animal hairs. They especially love fine fibers such as wool, alpaca, and cashmere. Balls of animal fiber yarns which are not properly stored are real treats for such larvae. In most cases, it is the outer layers of yarn which show damage. One indication for such pest infestation is that the positions of damage all lie very close together. If a carpet beetle was the culprit, the yarn looks almost as though it had been cut by scissors; moth larvae commonly only “nibble” on the yarn and don’t bite all the way through the strand. Often, the waste material of the pests can be found in the yarn ball. For example, if the yarn ball is held over a piece of white paper and then lightly beaten, a fine powder in the same color as the yarn may appear.
What can be done in order to prevent broken threads?
A lovely basket, full of beautiful yarns is certainly a decorative addition to any living area but to avoid unpleasant pest infestation, it is best to never leave your yarn stash and current knitting project in the open. Instead, store everything in well-closing bags or boxes. As additional protection, lay small bags of lavender or pieces of cedar wood together with your yarns; the fragrant essential oils serve as pest deterrents.