At the risk of sounding really stupid is it actually the four triangles that you fold and sew round the "glass". Sorry for my silly question but other than that I think this is a wonderful tut and definately will try it. I have a lot of animal and bird 31/2" squares which I would like to put in place of "glass" do you think they would look OK and what size would my first square need to be to suit these. Many thanks.