After running this all around in my head, scrutinizing the patterns directions, I came up with a formula that I think just might work. If:
x = desired size
y = original size
a = original tension
b = desired tension
Then: the adjustment factor need is
y/x times b/a
33/24 times 13/20
which equals 1.1188
Now my physics professor in college said that there's no point going beyond the second decimal place,
so I have a factor of 1.12.
So with the formula in hand I shall now try to see if it works by knitting this sweater for Emily, who is pictured at left in the last sweater that I made for her. It was a pattern that I found in a 1950's McCall pattern for a pleated skirt and jacket, with the sweater pattern thrown in for good measure. That was back in the day when it was assumed that women knew how to do all sorts of things. But then that's another story.
I will now make the sweater as long, relatively speaking, for Emily. And I'm really hoping that I can find a really cool butterfly button for the sweater.
Yarn: Plymouth Yarn, Encore Colospun
Tension: 5 sts per 10 cm
Needles: I'll have to check this out.
The sweater is knit from the top down.
Starting with the neck, using _____ needles, cast on 75 stitches.
Knit the next 5 rows - that's in garter stitch.
Make button hole: knit 2, yf, k2tog, knit to the end.
Knit the next row.
This next row is a tricky one. I think I will increase 44 stitches, which will give me 119 stitches.
First Increase row: knit 5, (M1, k1, M1, k2) repeat to last 7, then M1,k1, M1, k6 (119 sts)
Next row: knit
Start the yoke pattern:
row 1: k5, (p1tbl, k1) repeat to the last 6 stitches, p1tbl, k5
row 2: k5, (k1tbl, p1) repeat to the last 6 stitches, k1tbl, k5
Repeat these 2 rows 3 times.
Next row: knit
Second Increase Row: This will be increasing 30 stitches
k5, (M1, k3, M1, k4, M1, k4) repeat to last 15, then M1, k3, M1, k4, M1, k8.
to be continued