Thank you all so much for taking the time to respond to my question. It sounds like from your advice that this should not turn out to be a problem. I did use the selvage edges for sewing the lengths together to make the widths I needed. I also used a straight edge on the top to get the 90 degrees in hopes of making everything square as well as cutting carefully. It has been reassuring to hear your thoughts to confirm my ideas and also nice to know I'm not alone in having these kind of problems. Thanks again, you ladies you are awesome. :)