I am working on a block called snail trail. This is the first time I have tried working with triangles. I have put together the block pulled it apart and put it back together and I can't seem to get it to measure 9.5 inches. the squares were cut to size I checked twice before I cut the half trianagles. If you know the block it starts with 4 squares and builds squares in squares by adding the triangles. Is there some way to work the math to find out what each square should measure. That might help my final block measure up.

here is a link to the block.

http://quilting.about.com/od/quiltpa...ails_trail.htm

Thanks! I hope I explained this correctly.