## Eve Learns Math (and you can, too!)

Wednesday, April 4th, 2007Tags: Orangina, Techniques Tips & Tricks

So here’s a bunch of math so I can figure out how I should knit my Orangina. I’ve included my calculations so you can get an idea of the process I’m using, but I’ll summarize here by saying that I have a gauge of 14sts/4in which is way off the 24sts/4in that are recommended. With my wider gauge, I should get a wider shirt than the pattern would normally suggest. The cast-on number I’ve calculated, however (which corresponds to a 34in width in my calculations) corresponds to a 36in width in the pattern. That suggests that I would get a skinnier shirt, not a wider shirt, if I were to knit at my much wider gauge. I’ve never knit a shirt before, so I’m imploring for your suggestions. What should I do, knitters? I’m usually proud of my mathematical ability, but in this arena I’m stumped.

Here’s my math:

I figure that because it’s lace, it’s going to stretch a bit, even though it’s cotton. Given that there will be stretching and I don’t really care about length (that can be adjusted as I knit along), my gauge will be slightly approximated. I’ve measured the swatch in its stretched state (~7.50cm over a single pattern repeat) and its non-stretched state (~5.75cm over a repeat), giving me an average of 6.625cm per pattern repeat. That gives me 0.736cm (or 0.290in) per stitch. The inverse of 0.290in gives me the number of stitches per inch: 3.45. Multiplied by 4 inches gives me 13.8sts over 4in. That’s quite a bit short of 24sts, but that’s also taking stretch into account so I’m not sure how bad that is.

This is the part where you learn far more about me than you wanted to! I’m a size 34C, which means that I have a ribcage measurement of 29 inches and a bust measurement of 32 inches. I’ll use an inch of leeway (assuming the cotton will grow over time), which means I’ve got 33in*(14sts/4in) = 114sts. That’s in the general neighbourhood of the right sizing, but I don’t know if I should stick to the wide gauge or if I should go down a needle size or two. What do y’all think?

OK, I’ve knit Orangina before too, and wouldn’t say it is a particularly stretchy lace pattern, but I did knit it at a very fine gauge. I imagine that at a larger gauge, it is likely to stretch more.

The best suggestion that I can give you is about making the math a little easier. Each pattern repeat for Orangina is 9 stitches. You just have to figure out exactly how many lace repeats you need to get the right width, esp. since there isn’t any shaping. So, just for argument’s sake, say that 1 repeat = 2″. So if you measure 32″ around, then you need 1/2 that for one side of your shirt, so 16″. You would need 8 lace repeats, or 9×8 stitches, or 72 stitches, then add 4 more for the +4 that the lace requires, or 76 stitches.

Your own math might not come out quite so evenly, and I would not be afraid to let the circumference around the bust be a little smaller than your actual size, so that it does give you a nice, slim fitting garment.

If you notice, the way the designer sized this garment was just adding or subtracting lace repeats, so it is a simple as knowing how large each pattern repeat is at whatever gauge you are knitting, and knitting the right number of lace repeats to make the proper circumference.

Comment by Liz K.April 4, 2007 @ 10:24 am