Crimp Twist and Ply

The formula of crimp, twist and wheel ratios for spinning perfect yarns
How do you figure out how much twist to add to your yarn? One way, is to look at the fleece and spin with the crimp, rather than fighting against it.

If your end product is to be a thick, low twist yarn, then start with a fleece that has a lower crimp count, such as a Romney or a Coopworth. If you wish to spin a fine, high twist yarn, then use a fleece that has these characteristics, such as a Merino or a Cheviot. A lot of times I spin without paying particular attention to the crimp or the twist, but just spin for the pleasure of spinning and what feels right at the moment. But when I look at the yarn afterwards, I find that I have been spinning with the crimp for the most part. The fleece does know how it wants to be spun, naturally. Here is a more technical explanation of what happens, as I understand it.

Spinning with the Crimp

Lay the locks of the fleece you have selected against a ruler and count the number of crimps or bumps in the fleece. To spin with the crimp, the finished yarn will have the same number of twists as the original fleece has in crimp count.

Fleece Staple Length

If the fleece has 5 crimps per inch, then your finished, plied yarn should also have 5 twists per inch. If the fleece has 12 crimps per inch, the finished yarn is best spun to 12 tpi as well.

Formula of Twist and Ply

If you are starting with a Romney fleece that has 5 crimps per inch, and you wish to spin with the crimp, the plied yarn should turn out to be 5 tpi. How do you achieve this? To spin a 2 ply yarn, the singles spun yarn should be spun at 1.5 times what the finished yarn should be. When you ply the 2 singles yarns, in the opposite direction, 1/2 of the twist that you added into both of the singles, goes into the twist to create the balanced yarn.

Use this table as a guide of how to spin your fleece. But of course, you can alter the amount of spin of your yarn, depending on its intended use. For example, if you are spinning for socks, you might want to add additional twist to the yarn for increased strength.

This table is an approximation of the crimp in different breeds of fleece.
There is always some variation in fleece so please do try to figure out the correct crimp for your fleece.

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