The Z twist (twisting to the left) is the most widely used as it is suitable for most machines.

反捻(向左捻)使用最广泛，因为大多数机器适合这种捻法。

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However, it is customary to produce cotton and linen yarns with a Z-twist and woolen and worsted yarns with an S-twist.

然而，人们习惯性的生产棉和亚麻纱线时用Z捻，生产羊毛和精纺毛料纱线时用S捻。

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When it is rolled clockwise by your right hand, an S-twist yarn will become tighter and a Z-twist yarn looser.

如果你用右手顺时针的旋转它，S捻的纱线会越变越紧，Z捻的纱线会越变越松。

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