They're already pressed, but I will try again, PaperPrincess. Thank you.
Several days ago I watched
this video about the Log Cabin ruler. Marti Michell suggests cutting your strips on the lengthwise grain rather than crosswise for stability. Unfortunately, I am using a jelly roll and they're done crosswise, of course. If I ever plan another log cabin I will try to get yardage instead of pre-cuts and try her method. It certainly looks as if the direction of cut would help.