When Size Matters

Next to "How do I Double Weave?", the most frequently asked question I get is, "What size heddle do I use with my yarn?".

First you have to determine the sett for your yarn for the weave structure you want to make. To know the sett for your yarn, you have to know the size of it and use the chart below. If you don't know the size of your yarn, wrap the yarn around a ruler for 1/2" and count the number of times it wraps. That's the same number DPI (dents per inch) of the heddle to use for that yarn. This is known as "sett" or "EPI" (ends per inch).  Sett is a very important consideration for weavers

Yarn Sizes

8/4 Cotton: What does that mean?

These numbers tell you the weight, yardage, and number of strands in the yarn.  The industry standard is based on a single strand of cotton that has 840 yards in a pound. A 1/1 yarn would have a single strand of cotton and in one pound of it, would measure 840 yards.

In 8/4 yarn, the top number tells us the size of the threads. In 8/4 the thread used is 8 times thinner than the industry standard so you end up with 6720 YPP (840 * 8). The higher this number, the thinner the thread and more yards per pound.

The bottom number, the 4,  tells us the ply or how many of these threads are used to make up the yarn. An 8/4 yarn would be 4 very thin strands of yarn, which works out to 1680 YPP (6720 / 4).  8/4 yarn is in the "sport weight" category.

Here's a chart to show you the different sized yarns, the weight category and the recommended heddle size for plain balanced weave.

Yarn Type

Wraps/Inch

Yards/Pound

Recommended
Heddle Size

Ultrafine
(Lace or Baby Weight)

18
or more

2600

10 DPI

Fine
(Fingering Weight)

16

1900-2400

8 DPI

Medium
(Sport Weight)

14

1200-1800

8 DPI

Heavy
(Worsted Weight)

12

900-1200

5-6 DPI

Bulky

10

600-800

5 DPI

Very Bulky

8 or
fewer

400-500

4 DPI

For more information about "sett" and why it's important, check out some of these links:

http://peggyosterkamp.com/?s=sett&submit=Search (articles on sett)

https://www.interweave.com/wp-content/uploads/Master-Yarn-Chart-2014.pdf (Master Yarn Chart Free Download Highly Recommended)