Thank you so much for your comments and emails in last Tuesday's post! You let me know that you appreciated "the same or a bit more math, please" in these posts so you can more easily apply my techniques with the Farmer's Market Cardi to your own sweater-making. Thus: A Bit of Math it shall be. (Please continue to let me know via the comments if I am hitting the mark or not.)
The first order of business is to address some of the questions you asked. The questions centered around three things, so I'll take them one by one (I am so organized that way!).
How I chose the finished size of 43.5"
The first thing to do is Measure Thyself Properly. (A handy photo tutorial starring Yours Truly is here.) Most patterns list sizes according to the finished bust measurement, so of course, one wants to start by measuring one's bust.
Please note that this measurement has nothing to do whatsoever with your bra size. Measuring for a sweater involves wrapping an actual tape measure around your actual bustline at "its fullest point" (as we say demurely in the fashion industry). Go for it!
Then, you choose your preferred amount of ease (see below; more info is here) and add that to your bust measurement. Voila: Full Bust Measurement Plus Ease = Finished Bust Size, which is how most patterns designate size.
As it turns out, for the Farmer's Market Cardi, when I add my bust measurement (41.5") to my preferred ease (3"), the result (44.5") is smack-dab between sizes–right between the 43.5" and the 47". Now: I'm plump, so the waist, hem, and upper sleeve circumferences of the 47" size are more suited to my own measurements-plus-ease, but the armhole depth and shoulder-to-shoulder width of the 43.5" are a better fit for my smaller bust and relatively narrow shoulders.
So, the eternal question: Do I make the smaller size and adjust upwards, or the larger size, and adjust downwards?
The key to a great fitting sweater is, more often than not, bust fit. Armhole depth in professional patterns is proportional to fit in the bust area, as is shoulder width. (Notice I am avoiding the issue of cup size–this is due to space limitations, sadly. Go to Amy Singer and Jillian Moreno's splendid Big Girl Knits series for a wonderful discussion on how to handle differences in cup size.) The 47", while it fits me better at waist and hip, would give me a whopping 5.5" of positive ease in the bust; also, the armholes on the 47" would be too big. I have a couple of sweaters in my closet now that have 5-6" of positive ease in the bust; I only wear them at home whilst doing housework because I feel that I look rather sloppy in them. The 43.5" gives me 2" of positive ease; I can easily add more where I need it at waist, hip, and sleeve without having to do the rather complex calculations needed to adjust the armholes properly.
Thus, the decision has been made: I will make the 43.5" size, adding room in the waist, hip, and upper sleeve areas. Voila! With those adjustments in mind, and knowing I would do some generous swatches, I made sure to order an extra skein.
How do I figure out how much ease to use?
Choosing the amount of ease is always the tricky part. Not enough ease, and you end up looking like your sweater shrunk in the wash; too much ease, and you end up with a sweater that looks oversized and sloppy.
So how do you know how much ease you need to factor in? The answer: Look in your closet! This fall, I went through the sweaters I own and divided them into three groups: too big, too small, and just right. (Whoot! It's The Goldilocks Method!) I laid each sweater flat on the floor, then measured dimensions such as bust and waist circumferences, armhole depth, shoulder width, and hem circumference. (More on measuring the clothes in your closet is here.) I made notes as to what fit nicely ("I like the way this fits at the bust.") and what fit poorly ("These armholes are too big!" or "This sweater is HUGE on me!"). Then, I created a spreadsheet containing the basic measurements of these sweaters.
Now, when I want to knit a sweater, I can consult this handy spreadsheet, matching the dimensions given in the pattern schematic to those of similar sweaters I already own. If I know that I love the way my purple zip cardi fits around my bust (i.e., I like the amount of ease there) but I feel that the armholes of my grey button-up cardi are too big, I can use those data points to choose a size where the measurements are close to something I love wearing (my purple zip cardi) rather than something that I don't like wearing (my monster-sized grey cardi). And from my magic spreadsheet, I determined that in cardigans like the Farmer's Market Cardi, I generally prefer about 3" of positive ease.
When I pointed out that there was One Teensy Issue with my cast-on numbers, that garnered a lot of replies! Let's review:
46" hip measurement + 3" positive ease = 49 inches. 49 inches multiplied by 4.5 stitches per inch = 220.5 stitches, which I rounded up to 222 stitches to get an even number (this makes any mods easily split between left/right sides). As my belly is bigger than my behind, I added two additional stitches to the front on each side. The total? 222 stitches plus 4 stitches equals 226.
And that's where I noted that there was the One Teensy Issue with that number, 226. The problem is that when I added the two additional stitches to each side, I was adding a total of 4 stitches–or nearly one additional inch to my finished measurement. 226 divided by 4.5 stitches per inch = 50.2 inches, which is about one and a quarter inches more ease than I had planned on according to my careful spreadsheet. WHOOPS.
Of course, I did not realize this until I was on Row 17 of 226 stitches, which of course meant I had already knit 3800 stitches. (Whew!) The words of a friend echoed in my head: "Sandi, if you rip out all those stitches, I shall poke you with my dpn." Not wishing to be poked, even in my imagination, with her stiletto steel dpn, I chose to start the waist decreases early…and that is where we shall stop for now.
With one exception. I was a bit clever, and perhaps a bit crazy, and started something else along with the waist decreases: A steek. Find out all about my knitting mischief with steeks and waist decreases (oh, my!) next week!
If anyone has any questions, please leave a comment and I'll address those next week, too.
Joy and light to you this holiday season.