As I mentioned when introducing project, I decided to substitute a two-piece sleeve from another coat pattern for the one-piece sleeve in the pattern for this coat. My reason for doing this is simply that two-piece sleeves can often provide a nice fit and range of motion because they're of the way they're drafted, with ease at elbow joint and a slightly curved arm, so that the sleeve hem will fall toward the front of the body (similar shaping is also achieved in a single-piece sleeve with an elbow dart). Even when the arm hangs at the side of the body, it's still slightly bent, so the shaping of the sleeve accommodates this, as well as allowing the arm to bend easily.
The pattern consists of an upper panel and and undersleeve panel. I borrowed both the sleeve and it's armhole from Simplicity 4403 (now out of print) and aligned the armhole with the shoulder point and side seams of the Butterick bodice before cutting out my muslin.
The simplicity pattern instructions use basting stitches to ease in the elbow shaping of the sleeve, but I found that it worked well to ease in the fullness with extra pins and place the side of the sleeve that needed to be eased toward the feed dogs of the machine when stitching, using the movement of the feed dogs to pull in the extra fabric.
After completing the first seam of the upper and under sleeve, I pressed the curved area over a tailor's ham so that the seam would be smooth. For the second seam, I used a seam roll.
This picture of the back of the sleeve shows how it's curved toward the front of the body, even though the coat is just on my dressform and the sleeve is hanging "straight."















































