Let me start with a confession. I don’t always swatch.
When I’m knitting a scarf or shawl or baby blanket or a pair of socks for myself with the same yarn, needles and pattern that I always use, I simply wind my yarn and go.
Note that I have 40 odd years of knitting experience under my belt, so I can usually tell whether this was a bad idea or not within the first inch or two of knitting…
Swatch-skipping is to be avoided, however, if;
- you’re a new-ish knitter
- you’re knitting a garment that you want to fit properly
- you’re using yarn that you’ve never knit with before
The purpose of the swatch is to see if you can match the gauge on the pattern you’re knitting with the yarn and needles chosen. You know, the number of stitches and rows per inch the pattern tells you you need to get in order for the finished product to look like it does in the pictures.
Translation: a 4 by 4 inch blocked square knit in stockinette (or stocking) stitch on 5 mm needles should be 17 1/2 stitches across and 22 rows high. [Note that some patterns use ‘stitches per inch’ in their gauge instructions. Simply multiply those numbers by four to get the gauge required for a standard 4 by 4 inch swatch.]
Ideally, you’ll have chosen an appropriate weight yarn for your project and needles conducive to knitting with that weight. (Let me know if I need to write a blog post on this topic in the comments below; it’s a crucial first step to a successful finished object (FO)).
How I swatch (others may do it differently):
1. Using the needles suggested in the pattern, cast on the number of stitches required to get gauge over a 4 by 4 inch swatch. Cast on 50% more. Having too few ‘edge’ stitches will distort the swatch, rendering your estimate of gauge inaccurate. For the above example, that’s about 25 stitches.
2. Knit according to the pattern’s gauge directions (most often in stockinette stitch, but sometimes in the pattern’s more prominent stitch pattern) until you’ve got a swatch that’s approximately 5-6 inches in length. Again, having two few ‘edge’ rows will distort the swatch, rendering your estimate of gauge inaccurate.
3. Cast off all stitches loosely.
4. Wash swatch according to directions on yarn ball label (usually by hand and in cold or room temperature water). Press excess water out of swatch by rolling it up in a thick towel (I like to step on the towel-wrapped-swatch until no more water comes out).
5. Flatten swatch and pin out corners, taking care not to over- or under-stretch the fabric. Ideally, you’ll pin your swatch out to a size at which the fabric’s density appeals to you and is in keeping with the type of project you’re knitting.
6. Let swatch dry completely.
7. Without unpinning, measure out a 4 by 4 inch grid in the centre of your swatch. I use a contrasting yarn, pinning out the ends in the corners of my grid. Make sure that your contrast yarn is placed directly along a row and following a vertical row of stitches (look for the ‘V’s).
8. Count the number of stitches across both the top and bottom vertical lines. Ideally, you’ll get the same number for both. This is your ‘stitch’ gauge.
9. Count the number of stitches across both the left and right horizontal lines. Again, it’s nice if you get the same number on each side. This is your ‘row’ gauge.
10. Compare your measured ‘stitch’ and ‘row’ gauges to those indicated on the pattern. If they match, you win and get to start knitting immediately. If they’re off by more than 1/2 stitch or 2-3 rows, keep reading…
For most projects, ‘stitch’ gauge is more critical than ‘row’ gauge. (Warning, knitting requires that you’re comfortable doing a bit of math…)
Just think about it. If you’re knitting a sweater whose back is 100 stitches wide and supposed to measure 20 inches across (plus an extra 3/4 inch for side seams), you’d better be darn sure you’re getting a stitch gauge of exactly 5 stitches per inch (20 stitches over 4 inches).
If you’re off by even a single stitch, you’ll end up with a sweater back that’ll be either much too large (25 inches wide for a stitch gauge of 4 stitches per inch) or on the smallish side (16.7 wide for a stitch gauge of 6 stitches per inch). Not something you want to have happen when you’ve spent $100 or more on yarn…
Row gauge isn’t quite as important. You can adjust the length of a garment while you’re knitting it by paying careful attention to the measurements between instructions in the pattern. But width is harder to adjust. Particularly if there’s a stitch pattern in the knitting and you’re a novice knitter.
Didn’t get stitch gauge? Never fear. Make another swatch with a different size needle.
If you had too many stitches per inch in the first swatch, your needle size was too small (or your tension too tight) for the yarn and pattern combo you’ve chosen. Try a bigger needle. Go up a half or full size and repeat the above 10 steps.
If you had too few stitches per inch in the first swatch, your needle was too big (or your tension too tight). Try a smaller needle. Go down a half or full size and swatch again.
I always make sure to buy an extra skein or ball of yarn when planning my projects. That way I don’t worry about running out of yarn before I’m finished swatching!