I am trying to make my first quilt top and the blocks are set on end. When I finished all the blocks, I wound up having to cut off 1/4", so then my triangle pieces were too big. I went on line and found a site that tells you what size to make the triangles, so I could reduce their size too. This site was very helpful.
http://quilting.about.com/od/quiltse...ngtriangls.htm