Attach a carbide blade to your Multi Max. The size blade you need depends on the thickness of the grout. For example, standard grout lines require a 1/16-inch carbide blade while thicker grout lines require a 1/8-inch carbide blade.
Set the Multi Max to “high” if the grout is particularly old and hard. Select “medium” or “low” for softer grout.
Position the Multi Max’s curved blade inside the grout line. Turn on the tool.
Move the Multi Max in right angles along the grout between each tile. Apply gentle pressure. The carbide blade will sand out the unwanted grout, leaving only the tiles.
Wipe away any grout dust left on the surface of the tiles with a damp cloth.