Somewhere I saw a tutorial on how to sew these strips together so it compensated for the sometimes inconsistant 2-1/2 inch. I think it involved measuring in 2-1/4 inch from the left side of the strip to your needle instead of the right. That way your strip sets came out the right size as it was the seam that was variable, such as the top strip had 1/4 inch while the bottom might only have 1/8 inch material. I know I am not explaining it clearly, but if anyone can understand my blathering, and remembers this tutorial, please put me out of my misery and remind me where I can access it. Thank you soooo much!