Defining the Contour-driven Stepover Strategy

Below we are going to see how to do the first of these with a between contours operation on a small area of a part.

To create the operation, you define:

  • the geometry of the part to machine ,
  • the parameters of the machining strategy ,
  • the tool  to use ; you have the choice of end mill or conical tools for this operation,
  • the feedrates and spindle speeds ,
  • the macros .

Only the geometry and the guide contour(s) (strategy tab) are obligatory.
ll of the other requirements have a default value

Either:

  • make the Manufacturing Program current in the specification tree if you want to define an operation
    and the part/area to machine at the same time,
  • or select a machining feature from the list if you have already defined the area to machine and
    now you want to define the operation to apply to it.

Open file Basic2.CATPart, then select Machining > Surface Machining in the Start menu.

  1. Click Contour-driven .
    The Contour-driven dialog box is displayed.
    The dialog box opens at the geometry tab page .

  2. Right-click the red area of the icon, select the part as follows
    and click OK in the face selection toolbar to confirm your selection and redisplay the dialog box.

  3. Go to the Strategy tab and click Between contours.

  4. Go to the Radial tab,
    select Constant on part in the Stepover list and select the guides and stops as shown.
    (Click a label, select an edge and click OK in the Edge selection toolbar. Repeat this step for each label).

  5. Change distance to 5 mm.

  6. Select From guide 2 to guide 1 and click Tool Path Replay .

    The result is of an equal distance on the part surface from guide 2 to guide 1.
    Note the bottom of the machined area and how the paths remain perfectly parallel to each other
    but because of the shape of the surface they finish gradually on guide 1.

  7. With the same parameters, switch to Maximum on part and click Tool Path Replay .
    There is a variation in the distance between the paths on the surface but the paths respect
    both guide 1 and guide 2. There is no gradual finish on Guide 1 as there was with Constant on part.