The Drop Tilt Method (DTM) is a technique for positioning a tool over a curved surface part of a tool or die. The Drop Tilt Method generated tool position contacts the surface at multiple points (two) and the tool position and orientation can be achieved using a 5-axis CNC machine. In DTM therea retwo steps. In step 1 the tool is dropped along a vertical axis onto the curved surface to find the first contact point. in step 2 the tool is tilted, while retaining the contact at the first point, until it touches the surface at a second point of contact. This tool position and ortintation form one tool position. Numerous such tool positions form a tool path. The animation below shows the two steps of DTM as a tool positionis found for a concave surface.

The animation below shows the tool being positioned over a convex surface. DTM follows the same two steps. In step 1 the tool is dropped over the surface and in the second step the tool is tilted. It must be noted that the animation shows that the surface invades the convex hull of the toroidal tool. A real toroidal tool on a CNC machine has a relief at the bottom created by the positioning of inserts. This relief accomodates the interference without resulting in any gouging.