Ask Tara is a weekly-ish feature in which I attempt to answer your questions about spinning, dyeing or confusing knitting acronyms. If you have a question, ask it in the comments and I’ll answer it here with either a post or a video!
This week’s question was spurred by Laila of Rawfish.
She wondered:
Is there a name for yarn bigger than 8 WPIs?
But wait, what is WPI?
WPI stands for Wraps Per Inch. It’s a way of measuring the thickness of yarn.
Well, let’s back up a little more.
What we’re talking about is the diameter of a strand of yarn, but the industry standard way to describe this “weight”. I find that’s confused with the actual weight (like, 4 oz.), so for our purposes, we’re going to call it the “thickness”.
Commercially spun yarns are not measured in WPIs, but in stitches per inch. This is the measurement of how many stitches fit in an inch of St st knitting. It’s usually given as a range of numbers, as knitting styles cause variation in tension. Commercial yarns also contain “suggested needle size” and that can give you some insight into the thickness of a yarn.
Have you no standards?
The Craft Yarn Council of America has created an industry standard for measuring yarn: Numbers and Words! You can see in this chart how the numbers represent the weights (thicknesses) of yarn (0 is smallest, 6 is biggest) with corresponding “official” words (Lace through Super Bulky)
These measurement systems are all well and good if you’re looking at a ball band, but what about the yarn you just created? Do you need to knit a swatch to know if it’s worsted or super bulky?
Honestly, once you’ve knit with a wide range of yarns, you can usually figure it out by sight and touch. But relying on intuition for yarn I’m selling isn’t a reliable policy, so I use WPIs.
The reason so many spinners use WPI and many knitters haven’t?
- Spinners need to know the thickness without knitting it up
- Knitters want to know what it will be like after they knit up!
How to measure WPI
So simple! Get out a ruler, gently wrap your yarn around the ruler for one inch (from 1″-2″ or 5″-6″). Make sure the yarn isn’t being pulled too tight or overlapping or leaving gaps. You want to fill in that entire inch without stretching your yarn.
Now count how many times your yarn wrapped around – that’s your “wraps per inch”!
So what does it mean for knitters?
Well, WPIs can be translated (roughly) into an idea of what how many stitches/inch the yarn will produce. At the very least it will land you within the right number label.
Or at least, it should. While researching this issue, I came across quite a few WPI charts and all of them seemed slightly different. Some charts label a yarn with 7 WPIs Super Bulky and some just call it Bulky.
What do I do if a yarn is on the edge? Take a good look at the yarn, check this chart and use my common sense! If the yarn is very dense, I round it up to the bigger size (because the knitter/crocheter is going to get a bigger gauge). If the yarn is soft and fluffy, I’ll round down, knowing the yarn will smoosh into a smaller gauge.
But what to do with that “off the chart” yarn?
Well, friends, that’s where you come in! What do you think we should call the ginormous, bigger-than-super-bulky yarn? I asked that question on Twitter today and got some responses including “Jumbo”, “Gigantor” and “CrazySuperBulky”.
What do you think? What should be the industry standard in mega-yarn?
Resources:
Spindlicity article about measuring WPIs
WPI chart
Another WPI chart
Craft Yarn Council’s Yarn weight standards