You will have points to watch along the seam lines. Be sure they look the way you want them to before you go on. Some of my points refused to behave at the seam line so I cut out little flowers from one of the fabrics and appliquéd them over the offending areas (see right side of photo). This was a better solution than redoing seams until the fabric died.
TIP: Covering up faults is not cheating. It is called artistic innovation.
Another problem area may be the very center where all the wedges come together. This design has a lot of seams jammed up tight at the center point and it was impossible to put them together nicely. My solution was to make a 4 inch kaleidoscope of six small wedges from my feature fabric, and appliqué it over the bulky center. From the back I cut away the bulk.
TIP: One way to avoid problems in the center is to use a single fabric at the point of the wedge and choose a hexagon or octagon for your design (6 or 8 wedges). That chosen fabric could be fussy-cut to yield an interesting design. This solution would have to be included as part of the original design.
I have not tried it yet on a spiral quilt, but on my next one I am going to glue baste the seams together instead of pinning. See Christy Fincher's tutorial on this process. I tried it on a recalcitrant border on my current work in progress and it was fabulous. When you think about it, no matter how careful you are with pins, they distort the fabric. I have spent way too much time redoing seam junctions, and with spirals there are often more than two seams coming together. RaNae Merrill likes to keep the paper in until the seams are sewn. I prefer working with the fabric without paper so I tear off at least the seam allowance. You'll have to find what works best for you.
TIP: Take your time, work slowly and carefully, and it will be beautiful.
Pressing is a major issue as the bulky seams have a mind of their own. I just let them play their own game as long as the piece looks nice on the front. The only time I try to control them is when I have three or more seams at a junction. Then I like to have all the seams flat in the same direction so I end up with a nice little rosette at the center. That often means that a seam will have to twist somewhere along its length. To tell you the truth, I have never noticed those twists when the quilt is done and they don't interfere with the quilting. They are less bulky than the seam junctions.
Finishing requires placing the circular design onto a background, and I leave it to you to figure out how your special design will be displayed. I put mine onto a square or rectangular background by sewing large pieces of fabric onto the edges of the spiral however they will work and be easiest to sew. You can face the mandala, cut away excess fabric after it is turned, and appliqué it to a background. If you do this, you will have a circular border around the finished spiral. The heavy seams of the spiral will not turn under neatly so they have to be sewn in a way that allows them to lay flat.
This is the finished quilt that I have been describing. In my next post I will talk about quilting this type of quilt.