Pinwheels are among the more famous traditional quilting designs. Usually formed of a pair of colors —one a pattern, and one a solid color — they’re made by sewing two squares of fabric back-to-back. This doubled-square is then cut twice, on the diagonals. The resulting pieces are then pressed flat, resulting in four squares of two different colors. These are then pieced back together to form the pinwheel pattern.
You can form numerous other patterns, of course from these four half-squares. You can make diamonds, or arrows, or a range of other shapes. You’re limited to some degree by the fact that the pieces can only go in a few different configurations before they become repetitive, but it’s still a beautiful range of geometric forms produced from the original pair of procedures:
- sew two squares together along the perimeter;
- Cut them on the diagonal.
The intermediate steps look something like this. You wind up with stacks of triangles that have a seam along one side, and only one side.
You may be able to tell that at the moment, I’m working with a palette of three colors: green, blue and red. These are the leftover squares of fabric paired with each other after cutting up four two-yard-long sections of fabric. Apparently one fabric, the yellow, was considerably narrower than the other three — I had substantially fewer yellow squares than of the other three colors.
All the same, you should be able to see how the triangles, once folded out and pressed with the iron, become four squares. Each square consists of two triangular pieces of two different colors; those two different colors become the contrast in the pinwheel. Swap out two of the half-squares for squares of different colors, and the illusion of the pinwheel begins to dissolve into half squares.
Of course, you’re starting out with stacks of squares like this, and getting to these stacks of squares arranged in color variations is hard enough.
Each of these pairs of squares has to be sewn along its perimeter — four sides — and then sliced in an X through the middle to create the four squares.
There is another way to do it, of course. This is quilting. There’s always another way to do it. For this method, one defines one diagonal, and then sews a line 1/4″ out from that line on either side. One then cuts the diagonal with a ruler and rotary cutter, and one then has two half-squares. This Half-Square — the one made by sewing two-lines-and-one-cut, instead of the four-lines-and-two-cuts I described first, is apparently one of the most useful shapes in quilting. It can be trimmed down to a 6 1/2″ square from the 7 1/2″ squares quite neatly and with minimal waste — instead of losing a full 1 1/4″ all the way around, as shown in my first picture.
I’ll be trying these techniques both ways, and see which one works best for me.