Replaceable carbide grit-coated blades are 1/16" thick, which allows you to work with tiles that have a thin grout line. If you wish, you can add a total of 4 blades to the shaft (two on each side) to cut grout lines up to 1/2" in a single pass. Wider grout lines can be cut with a second pass. It is important to choose a blade thickness less than the joint width to prevent the tool from binding in the grout line and damaging the edge of the tile.
A single blade will clear grout from about 300 square feet of tile depending on how old the grout is and the type of grout used.