Loft with Start and End Constraints

You can control the tangency magnitude and direction of a loft between sketches, faces, or edges of surfaces.

When using guide curves, you can also control side tangency by selecting Tangency to Face under Guide tangency type.
Loft with side tangency not applied Loft with side tangency applied

To control Start/End Constraints:

  1. Create a loft.
  2. In the PropertyManager, under Start/End Constraints, select from these tangency types in Start and End constraint:
    Option Description
    Default Approximates a parabola scribed between the first and last profiles. The tangency from this parabola drives the loft surface, which results in a more predictable and natural loft surface when matching conditions are not specified.
    None No tangency constraint is applied.
    Direction Vector Applies a tangency constraint based on a selected entity used as a direction vector. Select a Direction Vector . If used as the Start constraint, select a plane (using the flyout FeatureManager design tree) or a linear edge or axis to define the Direction Vector .
    Normal to Profile Applies a tangency constraint normal to the start or end profile.
    Tangency to Face (Available when attaching a loft to existing geometry). Makes the adjacent faces tangent at the selected start or end profile.
    Curvature to Face (Available when attaching a loft to existing geometry). Applies a smooth, visually appealing curvature continuous loft at the selected start or end profile.

  3. Set the Start and End Tangent Length. Use the handles in the graphics area and drag to change the value, or enter the values directly in the PropertyManager. The tangent length controls the amount of influence on the loft. The effect of tangent length is limited up to the next section.
  4. Set the Draft angle to add draft at the start or end profile (available with Direction Vector or Normal to Profile selected).
    To set the Draft angle, you can also use a design table, or you can double-click the loft feature in the FeatureManager design tree. Double-click the values in the graphics area and change them in the Modify dialog box.
  5. To apply the Start or End constraint settings to the entire start or end profiles, select Apply to all under Start or End constraint.
    Apply to all selected

    One handle per profile controls the constraints for that entire profile.

    		 Apply to all cleared

    Multiple handles per profile control the weight of the constraints at individual segments within each profile.
  6. Examine the preview and if necessary, click Reverse Tangent Direction to reverse the direction of the tangent.
    Loft preview using no Start constraint or End constraint Loft using Tangency to Face for both Start constraint and End constraint
  7. Set the other PropertyManager options.
  8. Click .