Originally Posted by
Cedar
So here's where I really started questioning the 7/8 rule. I have. A small 1" square that I want to put in a square as a center motif. That means the the outside triangles have a 1" hypotinous and 3/4 inch square size finished. Would I really use a 1 5/8 sqare to make the outside triangles? Or is there a point where the rule breaks down? It's important to me to learn how to design my own blocks.
Sounds like you could use Deb Tucker's Square Squared ruler. Here's a link to her video:
http://www.studio180design.net/videos/?id=3
Her philosophy is to cut your pieces slightly over-sized and trim down to the exact size needed for your project. I just finished a t-shirt quilt and used her Tucker Trimmer ruler to make over 250 HST's. No matter how careful I am, my blocks always turn out a tad bit small when I only add an 7/8" to my blocks. It's more time-consuming, but I would much rather trim 256 blocks down to the exact 2.5" needed, then have 65 blocks that are only 2.25" when I'm done. Each of her rulers come with an instruction sheet that tells you exactly how big to cut all of your pieces to trim down to your desired size. The square squared ruler sounds like what you're trying to do. I am very happy with each of my Deb Tucker rulers.