I found that using wash away fusible featherweight grid to sew the small squares together is excellent to get perfect results. I can't find it anywhere now though. I took a class years ago and we made 1" square nine patches. We used the fusible and I bought it at the shop that had the class. The shop is long gone. It's the same method of making the Mondo Bags but the fusible washed away and was gridded for small 1 1/2" squares. I have contacted the ones I remember that took the class but they have no idea and most said they forgot all about it. Ugh. I guess drawing a grid on wash away fusible will be the way to go.