Snowball blocks are a nice alternative to plain blocks between pieced blocks, often creating interesting secondary patterns. I like to be able to figure out my own measurements, instead of having to look for a pattern or template, so that is why I want to share this with you.
The block that I want to make is a 6" block. 6" is the finished size, so we will begin with a block that is actually cut 6 1/2" square. Keep in mind that 1/4" seam allowances mean that pieces are cut 1/2" larger than their final size.
If I were making a 9-patch, I would cut nine little squares 2 1/2" x 2 1/2". That is the same size that I will cut the squares for the snowball corners. There is a little waste with this method, but it is much easier and more accurate than cutting an octagon shape and then trying to sew triangles to four corners.
With whatever fabric marker or mechanical pencil shows up best on YOUR fabric, mark a diagonal line corner to corner in one direction on the back of each 2 1/2" square. My fabric was so dark that the black pigma pen worked best for me. (DO NOT USE BALLPOINT PEN!)
Carefully line up a square on each corner of the background, right sides together, placing one pin in the corner out of the way, and another pin where the line of stitching ends. Sew directly on top of the marked line.
Trim 1/4" beyond each sewn line. Press the triangle corners out. Ta da!!
Here is what I made with my snowball blocks. One more project to be quilted, luckily it is a small one.
Apologies to the art quilters, crooked quilters, and PhD-in-math-quilters. I like it all and sometimes it needs to be accurate. Ha ha ha.