This local edit function provides draft to curved faces in a mold. It fills in gaps that are not visible from a specified direction. The purpose of this operation is to remove face regions with normals perpendicular to the draft direction. It introduces new ruled faces in order to remove regions from the nominated faces where the draft is thought of as being in shadow from a beam of light traveling with the draft direction and angle. It detects special geometry cases on spheres, cones, and Torii and makes a cone or plane for the taper surface rather than a spline.

Using the Function:

1. Select Shadow Taper from the Modify>Solid Face submenu.

2. Select a face to taper.

3. Choose a method for mold extraction vector. The mold extraction direction is very important as it determines the direction on which to base the angled silhouette curve, also known as an iso-cline curve. An incorrect direction vector will not produce the desired result.

• 2 points - Select the base point of the vector, then the tip point.

• Line - The vector will point in the direction of the chosen line entity.

• Vector - Select an existing vector.

• Tangent - Select an existing curve at its tangent location. Use The DynaHandle arrow to indicate position and orientation.

• Prp2Pln - Select an entity or use selection options to define perpendicular plane. Define either the Y axis or use Cplane Z Axis. Use the DynaHandle arrow to indicate position and orientation

• Keyin - Enter the I,J,K direction cosines of the vector. Cursor indicate the base position and move the DynaHandle arrow to indicate position and orientation.

4. Enter a taper angle. The face is tapered per your specifications. The special silhouette curve is calculated and ruled faces are added into the model and surrounding faces are extended and re-intersected with the new ruled faces. Some faces may be swallowed up in the process.

Below > The taper angle was 30 degrees. All five curved faces were selected at once for the operation by depressing the CTRL key and picking each face. The vector was used as the mold extraction vector.

Below > Both of the curved faces below were tapered using a 15 degree taper angle. The right vector was used for the mold extraction vector on the outside face. The left vector was used for the curved face nearer the center of the solid.