Designed to create parallel sides on boxes and vases the Robert Sorby Box Cutter is equally adept at creating flat bottomed surfaces and delivering those perfectly crisp corners on small projects. The Box Cutter is one of 14 specialised tips that support a range of tools and offer incredible flexibility to the turner. Sharpening: Use a diamond file or honing stone flat across the top face. To gain best results and increase the longevity of the cutter this simple procedure should be done little and often. Sharpening can be achieved with the cutter mounted on the tool.