Sizing up and knitting the 1945 '2 Colour Jumper for the Slim Figure' from a 30 inch to a 43 inch bust - plus link to free pattern

You can watch a video on how I sized up and knitted this jumper from 1945 on my YouTube channel here:

https://youtu.be/sWi10EUWTpQ?si=zu08WrCtQl4KGB8p

Recently I went through and organised my yarn stash, cataloguing every ball and skein including the amount, colour, ply and tension, so at a glance I could see what I already owned when I was going to knit a new project. This was to help me stop overspending and overconsuming craft supplies and to use up what I already had.

After cataloguing the (many) balls of yarn I had, I found several balls of double knit merino wool in different colours that I thought would go really well together as a garment.

I had grey yarn that was originally from Rowan that I bought second hand from a car boot sale and pink and purple yarn from Jaeger that was given to me by someone who was clearing out their stash. 

The Jaeger yarn was unfortunately hit by a moth attack and after washing, freezing, thawing and freezing it again, I was able to save the majority of it but it was then in smaller size balls, so I was after a project that I could use these oddments in so they were not totally wasted.

I came across this free pattern online ( Free Vintage Knitting Patterns – Stitchcraft August September 1945 – Vintage Knitting Pattern Archive) and thought the design would be perfect for what I was after, however it used 2 ply yarn and was only available in two sizes, 28-30 inch bust and a 31-33 inch bust.

I could have done what I have done in the past and used the same ply and needle size as specified and increased the amount of stitches I cast on, but because I had my heart set on using this yarn with this pattern, I thought that there had to be another way around it.

I’m a member of a few vintage knitting groups online and one way some people size up their patterns is to go up a needle size or two and change the ply. Using this method means you can be limited to how far you can size up to, however its still a good technique to learn.

So I thought I would look at the tension given in the pattern and work out some calculations. 

The original pattern used 2 ply yarn and UK needles size 11 and 12 (3mm and 2.75mm) and fitted either a 28-30 inch bust or a 31-33 inch bust.

The tension, unstretched, was stated as 8.5 sts to 1 inch.

So to work out the actual bust size of a finished jumper, I took note of the st count at the bust before armhole shaping and then divided by 8.5. I then times this number by 2 to get the full bust measurement.

28-30 inch bust pattern had 120 sts, divided by 8.5 sts = 14.11 inches, x 2 = 28.23 inches unstretched.

31-33 inch bust pattern had 132 sts, divided by 8.5 sts = 15.52 inches, x 2 = 31.05 inches unstretched.

To see if it was possible to size up the pattern without having to increase the amount of cast on stitches, I looked at the tension/gauge of the DK yarn I wanted to use.

The tension for the DK yarn I had was 5.5 sts to 1 inch, so I used the same stitch count in the original pattern to see if the sizing up would work.

120 sts divided by 5.5 sts = 21.81 inches, x 2 = 43.63 inches

132 sts divided by 5.5 sts = 24 inches, x 2 = 48 inches

I followed the pattern for the 28-30 inch bust using DK yarn and 4mm, using the same st count but adjusting the length for the torso and armholes.

I used the size chart from Craft Yarn Council as my reference point to help with length: https://www.craftyarncouncil.com/standards/woman-size

I used the grey yarn as the main colour and the pink and purple yarn as the contrast.

Following the instructions for the first size, I cast on the stitches and knitted 3 inches of k1, p1 rib before increasing.

The stranded colour work in this pattern was done in an unusual way in that the contrast colour was knitted back and forth and then the main colour was knitted back and forth, instead of taking both colours across at the same time. So a 4 row colour pattern feels like 8 rows.

 I came to think of them as 'half' rows, as you're knitting the contrast colour half of the row before knitting the main colour again.

The colour work pattern is 14 rows in total.

The first 6 rows are straight forward stocking stitch in your main colour and then it changes when you start the contrast colour stripes.

7th row: With contrast wool, k2 slip 2 alternately to end

8th row: Slip 2, k2, alternately to the end, bringing wool through to front of work between needles and slipping sts purl wise each time

9th row: With main shade, slip 2, k2, alternately all along

10th row: With main shade, p2, slip 2 all along 11th row: Using contrast, slip 2, k2, alternately all along 12th row: with contrast, k2, slip 2, alternately all along

13th row: With main shade, k2, slip 2, alternately all along 14th row: with main shade, slip 2, p2, alternately all along

And then you're back to 6 rows of stocking stitch in the main colour.

So when it comes to increasing and decreasing make sure which 'half' row you're on so you don't increase/decrease twice on the same row.

Below I've typed out how the 'half' rows create the 4 row garter stitch stripe.

Half Row 7 & 9 = Row 1

Half Row 8 & 10 = Row 2

Half Row 11 & 13 = Row 3

Half Row 12 & 14 = Row 4

So for example, after you finished the k1, p1 rib for the bottom of the jumper, you then inc 1 st at each end of the 6th row, which is the last row of the stocking st segment. The next 6th row will be Row 2 or the 'half' rows of 8 & 10, so you could increase on the half row 10 which is when you're using the main shade to p2, slip 2 to end.

 For the armhole depth I used Craft Yarn Council website for guidance. https://www.craftyarncouncil.com/standards/woman-size 

For my jumper, I knitted the armhole to be 8 inches in depth before decreasing for the shoulder shaping, whilst also keeping to the colour row pattern. The pattern matching on the sleeves was a happy accident and I followed the decrease rows according to the pattern, but I decreased to 36 stitches in the end not 30 before I cast off. I then did a running stitch through the top of the sleeve to gather the fabric tightly so I was able to ease and sew it to the shoulder.

For the buttonhole placket I cast on 5 stitches and knitted in garter stitch until it measured the same length as the opening. With the buttonhole side, I wanted the buttons to line up with the stripes and use colour buttons to match. to make the buttonhole I knitted 2 yarn over k2tog. For the collar, I cast on 8 sts onto 3.75mm needles, I worked k1, p1 rib for 20 inches in purple and then joined the pink yarn and carried on in k1, p1 rib for another 20 inches (40 in total) before casting off.

 For the shoulder pad, using 4mm needles, I cast on 20 sts and knitted until it was an even square shape and cast off. Folded it in half to make a triangle and sewed up the open sides. I then sewed the folded edge to the shoulder seam, where the sleeve attaches to the jumper. You can either wear the pad on your shoulder or as I have done, sew it so it's supporting the volume of the sleeve head.

The jumper fits well on me and does have stretch in it, so if the original tension given was unstretched and a jumper with a finished measurement of 28.23 inches fitted a 28-30 inch bust and 31.05 inch jumper fitted a 31-33 inch bust, then maybe a 43.63 inch jumper could fit up to 45 inch bust and the 48 inch jumper fit up to a 50 inch bust?

It might still depend on how tight or loose your natural knitting tension is, but it does open the pattern up to those who need a larger size.

Link to free knitting pattern available here: Free Vintage Knitting Patterns – Stitchcraft August September 1945 – Vintage Knitting Pattern Archive

Link to YouTube video here: https://youtu.be/sWi10EUWTpQ?si=zu08WrCtQl4KGB8p

Link to YouTube short here: https://youtube.com/shorts/-Krd0rQtGRc?si=ARDxtk9wIjtMvQF2