I drafted a straight UK Size 12, rather than draft for my personal measurements. First I drafted their bodice block, then used this to draft the slip. This book only shows drafts for one size. Sometimes it is easy to see how to change this for other sizes, other times, not so easy. Luckily for me, the size they use in the book is pretty close to my size.
I had to take it in a fair whack under the arms. I am wondering if this is a fitting, drafting or fabric choice problem. The slip is cut on the bias. The bodice block included 7.6 cm ease in the bust. I'm thinking that a bias cut, in a drapy fabric, will drop until it reaches a place it fits. So I'm thinking that I want very little ease. Admittedly, the technical drawing in the book did show an elasticised upper back edge.(On me, the slip stops dropping before the underarms fit, because it can't slide any further down my waist or hips...but you have to work with what you've got, don't you!)
I am wondering where the slip should sit. If I adjust the straps so that the empire line is under the bust, the bust point sits in about the right place. However, the slip feels more comfortable if I shorten the straps, so that the empire line is a little above the base of the breast. This does put the bust point in the wrong spot. (Either way, I will need to make some changes to get a good fitting cup.) I don't know if the improved comfort is due to the poisition of the empire line, or just because I am used to more coverage and higher underarms?
I'm not sure if you will be able to see the difference, but I will show photos with both strap positions.
Firstly, positioned below the bust:
Overall, I'm happy with it as a starting point, though I will do some more work on the cup draft. I'm thinking of changing the dart to a curved, vertical seam. This seam placement seems flattering in my bras, so why not try it in a slip as well?