Wood plastic screwdriver,wood screwdriver,good quality screwdriver,non-slip screwdriver henan horn tools co.,ltd. , https://www.hornhandtools.com Based on the practice and on the basis of the general round body forming turning tool, we deduced the graphic method and calculation method for the contour design of the circular body forming turning tool for machining the inner hole, which greatly improved the design efficiency, which is as follows: Shape and size, according to cutting conditions, workpiece material, tool strength, select tool radius r_1, rake angle γ_0, back angle α_0. Graphic method