I have 5 blocks left to cut and make. I only had a problem with one block. However, I noticed on several where a 10 inch block had units that were in 3rds so there were measurements of 1/8" or 1/16th inch. It made it really hard to have the block be exactly 10.5" unfinished. I also learned a tip from Bonnie Hunter. She said the line on the ruler should be on the fabric off. I found that just that little bit made a big difference in my blocks being the right siae.