How do you pick a sweater size when you are going to do some Bust Shaping? Most knitting patterns are set up with the Front and Back the same width. That works great if you are not curvy. If you are curvy, you want to add extra width to the front only where you need it. You do not need it in your shoulders or neckline. But which size do you knit?
The knitting industry uses the measurement across your bust for choosing the finished size. Add some ease and choose the nearest size to knit.
If you are going to add inches for bust shaping you need to begin with a different size. The simple answer here is to make a smaller size and add the needed width across the bust so that your sweater fits just like you want it too.
If you are knitting Top Down, you can use one, or combine two, of the Bust Shaping Methods here:
A more accurate way to measure for your size, might be to use your upper chest measurement. Add some ease to that measurement and choose your size.
My manikin, as you can see, does not have a big difference between her Upper Chest and Bust measurement. It must be a manikin thing.
Here is what I would do. I have a 3-4″/7.5-10cm difference between my Upper Chest measurement and my Bust. Usually sweater pattern sizes are set up in 3″/7.5cm increments. Ideally I would like an inch and a bit of ease added to this Upper Chest measurement. I would begin my Top Down sweater using the stitch counts for one size smaller than I really need according to my Bust measurement. I would work the neck down to just above the bottom of the yoke. The neckline and chest should fit nicely. Then I would decide which method I want to use for adding Bust width and continue to work, adding around 2″/5cm (and a little bit more usually) at the bust.
I then have the proper size according to my Bust measurement but more of the width is across the Front where I need it, for two obvious reasons.
Thanks for reading,
P.S. We do have two books where the Bust Shaping is included (built in to the finished sizes). In the Need A Plus Cardigan book the fronts are 3″/7.5cm wider than the back. In the Need A Circular Yoke the front is 2″/5cm wider.