Wonder if it's just me and having trouble using a straight-handled cutter!?! My go-to cutter is an old, blue, curve-handled Quilters Rule cutter which the HF blades don't fit. I tried 3 pkgs of HF blades and they all skipped. Used in 2 different cutters on 3 different mats. Now I keep one in an old brown Dritz cutter for paper piecing.