If you try this at home, remember that before the prepping and before the cutting, the very first step is always to choose a sweater knit fabric that you really love and one that will work for the particular project. And that's the part that I'm most pleased with. The fine merino wool was a great choice. The sweater is wonderfully soft, just the way I like sweaters.
Though there are a few online classes offered on "sewing knits", none that I've seen take the heavier sweater knit fabric into consideration. My resources for sewing were Revised Knit, Cut and Sew: Bk. 1 and The Complete Serger Handbook. I used both my sewing machine and my serger. Below are the instructions I wrote out for myself (with additional notes) so that I could remember what to do as I went along. I also wanted a written record in case I decided to tweak the procedure a bit the next time.
Step 1. Sewing machine: Machine baste Stay-Tape to Back shoulders. (I placed the Stay-Tape on the seam line, then machine basted along the upper edge of the tape. The Stay-Tape was lightweight and really worked well. I may try experimenting with clear elastic to see how I like it.)
Step 2. Serger: With a 4-thread balanced overlock stitch, stitch Front and Back together at the shoulder seams. Steam seams to one side, toward front of garment.
Step 3. Serger: With right sides together, stitch side seams for all ribbing (Front Neckband to Back Neckband, Front Hem Band to Back Hem Band, and Cuff seams) so that they form tubes. Steam side seams to one side, toward back of garment.
Step 4. Sewing machine: Fold ribbing in half horizontally with wrong sides together and zigzag-baste together raw edges. (I used a 4 mm width and a 4 mm length. In the future I may skipped this step, once I've had more practice.)
Step 5. Serger: With ribbing on top, stitch neckband to bodice matching side seams. (I "pinned" neckband to bodice first using binder clips and removed the clips as I serged. In fact, I always "pinned" with binder clip before stitching fabric.)
Step 6. Serger: Stitch side seams of bodice and stitch seams of sleeves. Steam seams to one side, toward back of garment.
Step 7. Serger: With ribbing on top stitch appropriate ribbing to sleeves, neckline, and bottom of bodice, always "pinning" first.
Step 8. Serger: Attach sleeves to bodice. (So that there's no extra bulk under the arm, after the ribbing is attached and before the sleeve is attached to the bodice, the sleeve seam directly under the arm must be steamed toward the front of the garment. This way when the sleeve is attached to the bodice, the sleeve seam goes toward the front and the bodice side seam goes toward the back.)
Attaching ribbing is where I had my biggest difficulty. After working my practice scraps I decided to use a differential feed at a click under 1.75. I still managed to overstretch the bottom of the bodice and sleeves when attaching the ribbing. Next time I'll raise my differential feed up to 2. For now I may try top stitching to see if that tames the flare any. Next time I may use the method described in this BurdaStyle tutorial (Steps 2 and 3), stay stitching before attaching the ribbing. If anyone has other suggestions, please let me know in the comments!
A special shoutout to the crafters of #VirtualCraftNight for their moral support through sweater construction. :)
So... I plan on redoing the bottom band and the cuffs. Though the flare is not too noticeable when worn, I'm all about process and I'd like to learn a method that works for me. And it's such an easy redo -- just a little re-cutting and re-sewing.
ETA On January 18, 2013 I posted a follow-up Further Notes on the Providence Sweater.