Double knitting is a clever technique that’s used to create reversible colourwork fabric. Essentially, it’s 1×1 rib where you’re using different yarns for the knits and purls. In order to create a stocking stitch fabric on both sides, you need to work all knit stitches with both yarns held at the back, and all purl stitches with both yarns held at the front.
In this guide Jen Arnall-Culliford shows you the basics of double knitting, including working in the round and flat, following charts, and casting off.
To find out how to cast on for double knitting, using the two-colour backwards-loop method, click here for Jen’s tutorial.
Working in double knitting
There are a number of ways of charting colourwork for double knitting fabric. The simplest of these is used for projects where the front and back of the fabric have the same pattern, with the colours reversed. In this situation, the pattern is usually charted by showing one side of the fabric. Each square of the chart then represents two stitches, rather than one stitch as is more common. It is easier to work in the round from a chart for double knitting than to work flat (as you will see in a moment).
Double knitting in the round
The colourwork pattern shown on Chart A below has a 6-stitch repeat, and a swatch has been cast on with the two-colour knit front and back method. It has been joined to work in the round, and is ready to work row 12 from the chart.
The first 3 squares on the chart are all coloured blue for yarn A, so this means that you work as follows:
*K1 in yarn A (with both yarns at the back of the work), then P1 in yarn B (with both yarns at the front of the work); rep from * twice more.
The next 3 squares on the chart are all coloured grey for yarn B, so this means that in the same way you’ll work *K1 in yarn B (with both yarns at the back of the work), then P1 in yarn A (with both yarns at the front of the work); rep from * twice more.
Continue to work from the chart in this way until you reach the end of the round. When working in the round, all rounds are worked with the ‘RS’ facing you, so the chart always shows you what shade to use for the knit stitches (and the other yarn is then used for the purl stitches).
Double knitting worked flat
It is slightly more tricky to create a flat fabric in double knitting. As the fabric is reversible, there isn’t really a right side or a wrong side, but we will use RS to mean the side that is shown on the chart, with the WS being the reverse colourway.
The first issue is that you need to twist the yarns together at the start of the new row, so that the fabric remains joined at the edges. This is actually easier than it sounds – simply take the new yarn for the first stitch of the new row from underneath the other yarn before knitting the first stitch:
This is the same way that you would twist yarns when working intarsia, and it ensures that you don’t get a gap in your fabric.
The RS row of the pattern is then worked in exactly the same way as described above for working in the round. It then requires a bit of mental gymnastics to work the WS row from the chart… First, you are reading the chart from left to right (as is normal for WS rows). And second, the first three squares on row 12 are shown as blue yarn A, which on the WS means to use grey yarn B to knit and then to use blue yarn A to purl. As before, you need to move both yarns from back to front as you go from knit to purl.
I found it tricky to be looking at the opposite side of the fabric and to have to reverse things in my head, so as with many things in knitting, the secret was to take my time and re-read the key slowly before working across each row. I normally find it fairly easy to read my knitting, so I know whether my pattern is lined up as I work the row. When double knitting back and forth, it’s trickier than normal to see how things are lined up, since you’ve got both yarns being used for each visible knit stitch on the front of the fabric (one is being used for the purl on the reverse). Once you’ve worked enough fabric, though, it becomes easier as you start to see how things are meant to line up. It’s worth persevering, as the finished fabric will be warm, bouncy and perfectly reversible!
More complex double knitting fabrics
Some patterns use double knitting to create a reversible fabric where the two sides have different patterns. These require a more complex charting method, since the knit and purl stitches in each pair may now be using the same shade rather than always alternating. In order to make this fabric, each row must be worked twice. On the first pass the yarn A is worked across all stitches indicated, with the remaining stitches slipped. And on the second pass, the yarn B is worked across the stitches that were slipped on the previous pass, with the yarn A stitches slipped. There is an excellent explanation and complete tutorial in Lynne Barr’s book, Reversible Knitting (Stewart Tabori & Chang, 2009) which not only includes several complex double knitting charted stitch patterns, but also designs using this technique.
To create a cast-off edge that matches the Italian two-colour cast-on edge used on the flat swatch, you can use the Kitchener stitch cast-off method (or Italian cast-off) as described in part 2 of the Brioche Masterclass in issue 105 of The Knitter. This creates a lovely rounded edge to your knitting.
For a simpler method, work as follows, using the main colour throughout:
SSK and pass the first st over the second st in order to cast it off.
Repeat step 2 until all sts are used up.
Break yarn and fasten off through final st.
When working in the round, the cast-off edge may also be worked as follows:
Pass the first st over the second to cast it off.
Repeat steps 2 and 3 until 1 st remains.
K1 and pass it over the last K2tog stitch to cast it off.
Use the tail of the yarn to neaten the join at the end of the round.
Double knitting in the round makes fantastically cosy double-sided cowls, such as the great ‘Spots’, ‘Dots’ and ‘Arrows’ designs from Hilary Smith Callis shown below. They’re available in her e-book Double Knit Three. It can also be used for reversible mittens or socks. Why not try casting on for a scarf or cowl and experiment with double knitting? We’d love to see how you get on!