I've been practicing and even built an FT3D that looks ok, but I struggle with my cuts. It seems that even with a straight edge, my cut lines occasionally aren't truly straight. What I mean is, no matter what blade I have, I struggle to keep it vertical the entire time, so many of my lines look beveled. I tried screwing a blade to a block of wood, but tightening it down too much bends the blade a little and doesn't seem to work well. Too loose and the blade doesn't stay put. Are there any tools out there or examples of tricks you guys use.