I am trying to piece a Jacob's ladder and the first block has not come out square. The instructions I have are using a method I have not tried before...they call it a "sandwich method for doing the triangle where you cut two 4 7/8 inch squares, mark a center line from corner to corner and sew a quarter inch on each side of the line and then cut it in half. For the 4 blocks, you sew two strips 2 1/2 inches wide together, then cut those up into 2 1/2 inch sections and sew again to make the 4 piece block. When I sewed all the pieces together for the block I found that I needed to really stretch the two blocks to match up with the edges of the triangles and then when I got the first block done it was still out of whack. I have remeasured my cutting and it is good and also measured the seams and they are 1/4 inch. Do I need to do a scant 1/4 inch for this block or do you have another suggestion? Thanks
The finished block is "supposed" to measure 12 1/2 square. As you can see, my sides measure anywhere from 12 to 12 1/2 inches.