A necessary part of becoming a proficient knitter is learning how to substitute yarns. Changing the yarn in a pattern for a different yarn can be necessary for a number of reasons, such as the yarn being discontinued, being made from a fiber you don't like or are sensitive to, being out of your price range or simply unavailable for another reason.
It is not that difficult to substitute yarns, but the prospect of finding the right yarn to complete a project can be quite daunting for beginning knitters. Here are some tips on how to choose the right substitute for a yarn given in a pattern.
Before you go to the yarn store or your favorite online shop to look for a yarn to replace the one used in a pattern, you need a little bit of information about the yarn that was used in the pattern.
The most important piece of information you need about the yarn in question is its gauge, or the number of stitches and rows per inch that the designer got when she or he worked the pattern.
So for instance in the fingerless gloves pattern knit with Rowan Big Wool, you can see that the gauge was two and a half stitches and three rows per inch knit in the round on size 15 circular needles.
That tells you that if you want your finished project to be the same size as the project in the pattern, you will need to find a yarn that allows you to knit that same gauge. Virtually every pattern you will ever come across will tell you what the gauge was, even if it says the gauge isn't important to the finished piece.
If a pattern doesn't tell you the gauge, it likely will tell you the weight of the yarn, whether its chunky, worsted, or fingering weight. Some patterns that give gauge will also tell you the weight of the yarn, which is handy information to help in your search.
Knowing the weight of the yarn can help you narrow down your search in the yarn store. You can ask to see only super-bulky yarns in the yarn shop if that is what you need, or most online shops have an option to search by weight. This will save you a lot of time by eliminating the yarns that simply won't work for you.
Finding the Right Fiber
Now that you know the gauge and weight of the yarn that was used in the pattern, you can begin to look for a yarn with a similar gauge to use for your project.
How do you know if a yarn has a similar gauge without knitting it? Most yarn bands will give you an estimate of how many stitches and rows the yarn works up to on a certain size needle over an inch or four inches. This is often presented graphically with a number of rows and stitches shown on a grid with a particular needle size named outside the grid.
Whether the gauge information is listed in words or as a picture, it's pretty unlikely that you'll find a yarn that perfectly matches the gauge that was given for the project you are looking at. That's because different companies use different sized needles to make their gauge swatches, and you might not find a yarn that indicates the same size needle your pattern calls for.
Even if you did, the gauge probably won't be exactly the same, and even if it were, that's no guarantee that when you make your gauge swatch you'll get exactly the same gauge.
Let's go back to the wristwarmer example. We're looking for a yarn that will get us 2.5 stitches to the inch (the stitch size is much more important than the row size, since you can always knit more or fewer rows to make the project fit). I like to check Yarndex, where you can search by weight and fiber, or you can just search online for things like "super bulky wool yarn" and see what develops.
Doing this I found Cascade Magnum, which knits up to 1.5 to 2 stitches per inch on size 15 to 17 US needles. With a little fiddling you could probably get the right gauge for this project.
Picking the perfect substitute yarn has a lot to do with your personal taste as well as the dynamics of the pattern. Don't pick a yarn just because it fits the math. If you don't love it, keep looking.
Once you find the right yarn, how do you know how much to buy?