Originally Posted by rebeljane
I would like to make some 6 1/2" pinwheel blocks. I want to use the 2 square method using 1/4" seam around the 4 sides then cut diagonally to make 4 half square triangles. My question is how big do I have to cut the 2 squares? Hope I have made this clear but am sorry if I have not. This is the first time posting and I have no doubt there is someone out there who can help me. Thank you in advance.
When we were doing the pinwheel project a member, Ceil, came up with this formula that works!
"Whatever your block side is subtract .5 then multiply by 1.4 then subtract .5. "
So you would have:
Start with a 5.5 inch square
5.5 minus .5 = 5
5 x 1.4 = 7
7 Minus .5 = 6.5
Try it on some scrap fabric.
If your seams are a true 1/4" it should work.
If it is a little small try starting with 5 3/4" and trim finished block.
If it's a little big trim back.
HTH
Edit to add: Yes, as the others have said starch or sizing is a must before you cut out the squares.
:-D