In workpiece apparently the method of car groove calls grooving, groovy appearance has outside groove, inside groove and end panel chamfer. If pursue,1 is shown. Graph the method of 1 commonly used grooving 1. The choice of grooving knife often chooses grooving of knife of high-speed steel grooving, the geometrical appearance of grooving knife and angle are shown 2 times like the graph. Graph knife of grooving of 2 high-speed steel 2. The methodological turning precision of grooving is not tall with width narrower rectangular groove, can be equal to the grooving knife with wide chamfer with Dao Kuan, use take a way continuously the car goes. Precision demand is higher, divide second car to become commonly. The groove with wider turning, can use the straight cutting that take a way for many times (see a picture 3) , leave certain fine vehicle surplus in two side of groove, next according to groove vehicle of wide choice of deep, chamfer comes dimension. The round deep-slotted chip breaker with lesser turning, use turning of figuration lathe tool commonly. Bigger circular arc chamfer, motor-car of couplet of usable both hands is cut, check nap with example. The echelon chamfer with lesser turning, finish with figuration lathe tool commonly, bigger echelon chamfer, normally first car straight chamfer, enter law or law of or so cutting to finish continuously with echelon knife next. Graph 3 cut wide chamfer CNC MillingCNC Machining