It isn't paper pieced. Wish it were. Each separate row is cut from a template. The paper template that I glued together includes the 1/4" for seam and my piece is almost 1/4" larger than that. I suspect that the templates are slightly off and hoped that I could use some mathematical method of checking each row and trimming if necessary. I was hoping that checking the 45 degree angle would help, but as the rows are of different widths, I don't know how to check for that.