I'm using Hobbs 80/20 and the package says to quilt 3.5 inches. I'm working on a quilt that is 50 x 60 with 10 inch blocks - simple rail fence. I've stitched at 5 inches and if i need to stitch closer I will need to stitch at 2.5 inches to stitch in the ditch. I'm attaching a photo but the lines I drew on it didn't show up - I'm going to try again. You might be able to see the stitching...