I goofed. I didn't pre-wash my fabric for the Burda jacket and will now have to dry clean it so it won't shrink. Why didn't I take the time to pre-wash? I don't know. I guess I was impatient and eager to start working on it. I also thought it was polyester, like most of the fabrics I've used lately and those didn't need pre-washing. But I've discovered that the fabric, shown in the picture, is rayon. It's a burnout rayon - the leaves are a black mesh and the rest is gray knit. And it does indeed shrink. I washed a 3 inch square sample ('cause that was the size of the quilter's ruler I grabbed) and it shrank 1/8 inch in both directions. Phooey. I hate dry cleaning.
I suspected the fabric wasn't polyester when I started working on the flounces. I want to use a serged 3-thread rolled-edge to finish the bottom edge but I'd never done that before, so I tried some samples. It's a good thing I practiced first because I discovered that the stitching comes off the edge, especially when it's stretchy. The flounces are curved pieces, like the letter "C", so the edge of the fabric has portions that range from straight of grain (stable) to bias (very stretchy) to cross grain (stretchy). I went to my sewing library and The Ultimate Serger Answer Guide by Baker, Brown and Kacynski suggested stabilizing the edge. No problem, I have lots of wash-away stabilizers on hand. So I tested a sample and it went perfectly - all the stitches stayed on the fabric. When I washed out the stabilizer and found that the fabric went very heavy and somewhat stiff, I realized that I wasn't working with polyester. A burn test was in order.
I'd never done a burn test so I consulted Sew Any Fabric by Claire Shaeffer, which has a nice table of the burn characteristics of many fabrics. I had my husband help me - he has an acute sense of smell and has done scientific experiments, so I knew he'd be up for the task. The verdict was clear and unmistakable: rayon. The piece of fabric went up in flames very quickly. Scarily fast in fact. I will remember to never, ever wear this flouncy-sleeved top near open flames. The sample smelled of burning paper or wood, and in fact rayon is made from wood pulp. It was patented in 1894 as an artificial silk. Most rayons shrink when washed and some shrink multiple times.
So now I will have to come up with another way of stabilizing the flounce edges so I can serge them with the rolled-edge. I'm leaning toward cutting strips of fusible interfacing or using the (more expensive) fusible straight tape. At any rate, the jacket is on hold until I try some more samples. The only thing left to do are the flounces and the snaps (instead of buttons). Here's a sneak peek: