Archive for November 9th, 2008

There are two widely used methods for measuring spun yarn. One, the yards per pound measurement, is usually taken using a piece of equipment called a McMorran Balance. There’s a good article in the Summer 08 Spin-Off explaining this. A McMorran measurement, however, won’t really tell you how thick your yarn is - a heavy, drapey fingering weight may come up at the same ypp (yards per pound) as a light poofy DK, as the yarns each have the same amount of fibres, just spun in a very different way. Measuring the wraps per inch (wpi) will tell you the exact grist (thickness) of your yarn, although it won’t describe the density for you. Combining both measurements will give you the most complete picture.

Firstly, why would we even measure wraps per inch? Well, a few reasons. Taking notes of measurments such as grist, ratios spun and so on, gives you valuable information should you want to recreate the yarn at a later date. It may be that you want someone else to be able to recreate the yarn - e.g. in a published pattern. The more information you have, the better.

Measuring the wpi is also a good way to check a substitute yarn. Commercial yarns give a gauge on the ball band, but rather than knit swatches with all your handspun to find a match, you can simply measure the wpi of the commercial yarn, and those of your handspun skeins. Knowing the wpi can also give you a starting point for needle size - there’s a handy table in this article listing wpi and equivalent gauge.

So how is it done? Measuring wpi is quite simple really, however there are variables in play and it’s a good idea to practice a bit to make sure you are consistent. Instructions such as ‘wrap evenly and not too tightly’ are actually quite subjective, you may wrap ‘not too tightly’ with different judgement to someone else. If you know that you are always consistent yourself, then that is a good starting point.

Specially made wpi tools like this one are handy, but not essential. You can wrap your yarn around anything with measurements marked on it - or even a piece of dowel with tape markers. Wrap slowly and evenly, placing each layer next to the last without squashing them. This is much easier with smooth, drapey yarn than soft and puffy!


Continue until your inch is full - don’t be tempted to stop at half an inch as your reading may be inaccurate. Check that the yarn is not too tight or too loose, the threads should be touching, but not squashed. This yarn measures 12 wpi.


And that’s all there is to it! Practice measuring your yarn - find some commercial yarn you think looks the same as your handspun then measure them both to see how close you were. Measure different parts of your skein to check whether it’s even. Measure everything in sight until someone gets tired of you and takes away your ruler :-)


I have two little wpi tools to give away this week - leave me a comment telling me what you’re spinning today and on Thursday morning I’ll draw some names out of the proverbial hat. Good luck!

Don’t forget, we’re now on Lingr. Pop by today for a chat :-)


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