Summary The original file that I took this from was completely unusable. Re-created it so it works and is printable. Flat on one side prints great and is a great, and cool, letter opener. Recommend 0.1mm layer height for best blade toughness. If you use 0.2mm you'll likely need to trim off the first layer from the blade edge. Print Settings Printer Brand: RepRap Printer: Prusa i3 MK2 Rafts: No Supports: No Resolution: 0.1mm Infill: Minimal Notes: See description.