I have used this method before, on a smaller scale, to make parts of Ohio Star blocks. I thought it would work well to make the 12 inch squares to go between my pieced blocks.
Step 1. I added 2 inches to the size block I need finished, at the end. Since I wanted the blocks to be 12 inches when finished, I cut out 14 inch blocks. Here you see one red and one white. I drew a diagonal line across the squares, put them right sides together, and sewed 1/4 inch from BOTH SIDES of the line.
Step 2. Cut on the diagonal.
Step 3. You now have 2 squares that are made of two triangles - one red and one white. Iron the seam allowances towards the red.
4. Draw the diagonal on the wrong side of one of the blocks. This should be the diagonal that crosses both colors.
(GEOMETRY TEACHER ALERT! Since a square is a rhombus, this diagonal will be perpendicular to the other diagonal - the seam you have already sewn. Since a square is also a rectangle, the diagonals will be the same length.)
Step 5. (You can just barely see the line I drew in this picture on the white fabric) Line up the squares with right sides together and opposite colors facing each other. The red will touch the white. You can FEEL that the seams line up since the seam allowances are ironed toward the red.
Step 6. Sew 1/4 inch from the diagonal you drew on each side of the diagonal.
Step 7. Cut through the diagonal.
Step 8. TA DA!!! You have two 13+ inch squares that are made of quarter square triangles!! These are easily trimmed to the correct size.
Since I used these in a Quilt-as-I-go method, I actually left them BIG and will cut them down later. It gives me some fudge room as a quilt. You might also be able to see that I used two different reds in this square. After Step 3, I switched some of my squares around so different reds would be next to each other.
Here is a picture of the quilt when it was on my design wall. (Yes, I know there is one setting square in the wrong position) I have, since, pieced them all together and added a border. I am currently hand finishing the seams on the back squares and should be done soon. Then I will add a little more quilting in the borders, add the binding and be DONE....
...Done with my July project!! And Done with Red. I have used up most of my red stash in this project. YEAH!!!
Stay tuned, however, because I hope to catch up and also finish my August project in August!!
Oh.. I am seeing red.