Rake angle

rdf:langString Rake angle

rdf:langString Rake angle is a parameter used in various cutting and machining processes, describing the angle of the cutting face relative to the work. There are three types of rake angles: positive, zero or neutral, and negative. * Positive rake: A tool has a positive rake when the face of the cutting tool slopes away from the cutting edge at inner side. * Zero rake: A tool has a zero (or neutral) rake when the face of the cutting tool is perpendicular to the cutting edge at inner side. * Negative rake: A tool has a negative rake angle when the face of the cutting tool slopes away from the cutting edge at outer side. Positive rake angles generally: * Make the tool more sharp and pointed. This reduces the strength of the tool, as the small included angle in the tip may cause it to chip away. * Reduce cutting forces and power requirements. * Helps in the formation of continuous chips in ductile materials. * Can help avoid the formation of a built-up edge. Negative rake angles generally: * Increasing the strength of the cutting edge. The tool is more blunt. * Increases the cutting force. * Increases the power required for a cut. * Can increase friction, resulting in higher temperatures. * Can improve surface finish. Zero rake angles: * Easier to manufacture. * Easier to resharpen. * Less power and cutting forces than a negative raked tool. * Chip will wear and 'crater' the rake face.