I have not seen a version of Butterick 4985 that I haven't loved, so I put it into my sewing queue. I plan to use it on some pinstripe silk dupioni I got from Paron at PR Weekend 2007, but since it's such a nice fabric I figured I'd make a wearable muslin first. I used the fabric I got at Fake Paron in NYC when I went there in March to see Xanadu (warning: site plays music), which is closing soon on Broadway I hear but will be touring. If it comes to your city you really should see it. It's hilarious. I saw Ricky from Season 4 of Project Runway in Fake Paron, which was my celebrity sighting of the trip.
Anyway, I wanted to emphasize the corset-like lines of the lower bodice, and I decided piping was just the thing.
I started by cutting strips of fabric two inches wide. For the vertical piping I just cut on the grain; for the piping around the neck I cut on the bias so I'd have better flow. I chose the width based on seam allowances of 5/8". If you use wider or narrower seam allowances, adjust accordingly. Remember that part of your width will be taken up with the piping.
Using your zipper foot so you can get snug against the cording, fold your piping strips in half and run cording down the fold. I used rattail braid I had handy. After the piping is made and cut for the seams, I sew over the top to keep the cording in place but leave the bottom loose so I can trim the cord at the hem.
Again using the zipper foot, pin the piping into your seams and sew. As you can see, the two inch width on the piping strips ends up with perfect piping at a 5/8 inch seam allowance. Just line up the edges of the piping with the edge of the seam allowances and you're all set.
Finish your seams and press them open. Pressing didn't smush down my piping, though you do have to pick which side you want your cording to lie. You can see that I made this before I got my serger. I kind of want to go back through years of projects and serge all my zigzagged edges.
When hemming, you want to cut the cord slightly above the hemline so you don't have too much bulk, which can make your hem all bulgy. Press the hem under and then pull out your cording. Mine was easy to trim because I could see the fold that had been pressed into the cord and trimmed a little above the fold. You can also measure to double check. When you sew your hem, break the stitching at the piping so that you don't smush the piping and/or have glaringly unmatching thread.
The piping on this came out really cute, though I need to open up the right side of the collar and trim the neck piping even more, as it sticks out a little. All photos of this project are here and the review is here.