Right tool radius compensation.
G42 is a G-code used to activate the right-hand cutter radius compensation. Cutter radius compensation is a feature that allows the machine to adjust for the radius of the cutting tool when performing certain operations. By activating the right-hand cutter radius compensation, the machine will move in a path that compensates for the radius of the tool on the right side of the workpiece, so the cutting tool will be tangent to the programmed path.
The G42 command is typically used before or during a specific operation, such as contouring or profiling, to ensure that the machine is following the correct path that compensates for the radius of the tool.
G42 G42 <D> G42 <P>
G42