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
by selecting Tangency to Face
under Guide tangency type.
To control Start/End Constraints:
Create
a loft.
In the
PropertyManager, under Start/End Constraints,
select from these tangency types in Start
and End constraint:
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.
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.
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.
To apply
the Start or End
constraint settings to the entire start or end profiles, select
Apply
to all
under Start or End
constraint. If cleared, multiple handles allow you to apply a weight
to the constraints for individual segments within a profile.
Examine
the preview and if necessary, click Reverse
Tangent Direction 
to reverse the direction of the
tangent.
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|
|
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Loft preview
using no
Start constraint or End
constraint |
Loft using
Tangency to Face for both Start constraint and End
constraint |
More examples of loft tangency options
Set the other PropertyManager options.
Click OK 
.