I hear it all the time from students.
"But I hate knitting a gauge swatch!"
And they hear this back...
"If you want to be surprised at the fit, if you want to have wasted 30 or 40 hours knitting a sweater that the recipient can never wear, then don't knit a gauge swatch.
Sure, we see this little icon on every ball and skein of yarn we buy.
It means that the manufacturer only suggests using a certain needle size to achieve a certain number of stitches per inch knitting in Stockinette Stitch. In this case size US 8 (5mm) needles might give you 5 stitches per inch.
Might? Well, sure. I knit loosely and would probably test out size US 6 (4m) needles first. Then I'd go up to 7s (4.5mm), 8s (5mm), or maybe even down to 5s (3.75mm) all the while looking to achieve the number of stitches per inch called for in my pattern. And if you don't think there's a big difference between 3.75 stitches per inch and 4 stitches per inch, just do the math. One quarter of a stitch per inch adds up to 10 stitches in a 40" sweater. And that can turn your 40" sweater into a 42.5" sweater, yikes!
But is there really that much difference in the way different people knit the same yarn? I mean, if the manufacturer says 5 stitches per inch on US 8s (5mm), didn't they test that? Isn't that what most of us would get?
This is from Jacqueline Fee's The Sweater Workshop. The image on the right shows three different gauge swatches knitted by three different knitters. All knitted with the exact same yarn and needle sizes. It this doesn't show you that you need to test your gauge I don't know what will.
But what's the gauge swatch on the left? Jacqueline tested her yarn with 11 different size needles to get a gauge she liked. Wait a second cowboy, a gauge she liked? I though we were talking about looking for a specific gauge that a pattern might require? Well most of the time that is what we're looking for in knitting our gauge swatch. But sometimes we are just looking to be creative. To find a knitted fabric that we love and create something from that.
This is from my book Knits Men Want. Every pattern starts like this, with size across the top and gauge along the side. Sure, you can use the yarn I picked for the project and go with the gauge I liked and knitted the sample with (not always what the manufacturer had in mind). Or, you can choose any yarn, knit samples on all sorts of different needles, choose the knitted fabric you like best and measure your gauge (that is, stitches per inch). Go across the top for your size, down list to find your gauge of choice, and voila, you get what you need - be it yarn requirements or the number of stitches
And remember, you've made the commitment and bought the yarn and you're going to commit weeks to the project. So, even if you spend the entire first evening on a new project knitting gauge swatches, know that it is time well spent.