Sharon, that is why I have made so many of these....each one is different... the only strip of material I cut to uniform size is usually the middle one .. however on the one I did for my dad I made them ALL 2 1/2 inch strips... I was still able to use out of my scrap stash and still have a ton left so plan to do more....I think the difference in the looks of each quilt is what you use for your focus fabric in the centers ...I have also made many without matching the centers by size or color and they still look great!!! Its a great method..
My MIL taught me how to make these way back in 1975, before they were even called "string quilts"...she referred to them as newspaper quilts as we used newspaper for foundation. I've made alot of them for charity raffles and people really go for them....