Guided loft: Create a surface using birails

Description: 5 minutes; Lab exercise: 20 minutes

Birail curves define the paths for the profiles to follow and are interpolated by the created surfaces. Use birail curves to add the surface to an existing part or to create a more complex shape.

When using birails, choose from four options:

Conditions for birails

Limitations

For more about using birails, see Guided loft: Create a surface using unidirectional scaling.

Lab exercise

Prerequisites

Using one birail

  1. Load the vase.pkg file.
  2. Click Surfacing .
  3. Click Guided Loft in the Create Face section.
  4. Select the straight line as the Spine.
  5. Select the circle as the Profile Edges (two curves).
  6. Select the curve as the Birail Edges. The Isotropic option is on by default.

  1. Click Preview.

  1. Click to complete the operation.

Because there were two profile edges that made up the circular profile, the resulting vase has two surfaces.

 

Try this lab again by changing the scaling options to None and Unidirectional. Bidirectional will not work because there is only one birail.

Birail Scale: None

Birail Scale: Unidirectional

Using two birails

  1. Load the bidirectionalscalingwithbirails.pkg file.
  2. Click Surfacing .
  3. Click Guided Loft in the Create Face section.
  4. Select the straight line as the Spine.
  5. Select the two circles as the Profile Edges (two curves).
  6. Select the two curves as the Birail Edges. The Isotropic option is on by default.
  7. Click Preview and view the model from the top (Z direction).  This will give you the best view of how the shape changes according to the birail scaling option you choose.

Isotropic

Unidirectional

Bidirectional

  1. Choose an option and click to finish.

Integrate a surface

Birails can be used to integrate a surface into a given model. The profiles are translated, rotated, and scaled in order to make the surface fit to the birail curves.

  1. Load the twobirailsforpartintegration.pkg file.
  2. Click Surfacing .
  3. Click Guided Loft in the Create Face section.
  4. Select the straight line as the Spine.
  5. Select the both ends of the model as the Profile Edges.
  6. Select the top and bottom of the empty space as the Birail Edges. The Isotropic option is on by default.
  1. Click to integrate the guided loft surface into the existing surface.