My mom and I did a ladies day out for my birthday on Wednesday - we were actually picking up my car (it had some engine work done on it), so we made a couple stops on the way home. One was a quilt shop we had never been to before. I finished my civil war quilt top recently, so I was looking for a backing suitable for it. I found a brown/cream print in the clearance section of the quilt shop - it was marked $5/yard. Then, they had a coupon for an extra $2 off - so it was $3/yard! THEN, when I was having it cut (I got 5.5 yards), my mom mentioned giving me my birthday money - and the clerk mentioned they give 20% off for birthdays. So, 20% off the $5 was $4 - then $2 more off - making the material $2/yard!!! So, even with tax, the backing was only $12-something!!! What a deal!
Anyhow, I realized quickly when I got home that I should have gotten another 3 yards - my quilt top is 90.5''x90.5''. Usually, I will piece in material from the front to make up in width, but I really didn't want to do that on this quilt. So, I used this calculator/technique and found I had JUST enough to make the quilt backing JUST BARELY big enough.
I did it a tiny bit different - instead of moving the triangles until it was the width I needed, I estimated how much offset it would need and cut 7.5'' off of the tips of the triangles before sewing the diagonal back together. If I do it again, I think I will do only 7'' because it is barely long enough, but plenty wide now (it is 91''x94''). This is the most common size quilt that I make, so I am sure I will be repeating this.
This is how the seam looked on the back:
And, on the front, you can barely tell it is pieced!
Success I would say!!!