The Oval designer is accessed using the 'New' command. It is a special design feature for
designing a single oval pipe/cone, with or without skew, that can be unfolded. An oval differs from
an ellipse in that it has four sides each with a radius, with each side smoothly meeting the next
tangentially. The ellipse, on the other hand, has a continuously changing radius of curvature.
The Oval designer is a standalone feature and the oval pipes/cones cannot be transferred to the
3D environment for intersection with other parts as they can for many of the other Special
designs.
There are two possible cases shown below, selected via the Symmetry parameter which can be
set to either Symmetric, or Asymmetric. In the symmetric case the radii on the opposites sides of
the oval are kept the same. In the asymmetric case they can be different.
Fig: Special Oval Design Feature - Symmetric Case
The next case is the asymmetric case allowing greater flexibility
Fig: Special Oval Pipe/Cone Design Feature - Asymmetric Case
Parameters
Symmetry: Option - This option can be set to either Symmetric, or Asymmetric. In the symmetric
case the radii on the opposites sides of the oval are kept the same. In the asymmetric case they
can be different.
Show-Radials: Boolean - This option can be set to None, Ends, Arcs or All. Its setting affects
both the display and output of the oval. If set to All then radial lines are shown on all sides. If set
to Ends then radial lines are shown on the Ends sides only - which can help with visualization. If
set to Arcs then radial lines are only shown on the oval sides. If set to None then no radial lines
are shown on the oval.
Length: Value - This is the vertical length/height of the oval. The center line may be longer if the
piece is skewed with eccentric offsets, but the vertical length is always the same regardless of the
skewing.
Seam: Angle - Defines the position of the seam on the oval, on the side selected in the Seam-Seg option.
Seam-Seg: Option - This option can be set to 1-Arc, 2-Rad, 3-Arc or 4-Rad defining one of the
four sides of the oval where the seam should be placed.
Width Eccent: Value - Defines the skew offset in the direction of the Width of the ellipse. The top
is therefore moved away from alignment with the bottom so that top and bottom are no longer
inline. This does not affect the ability to unfold the ellipse and get a perfect result without twisting.
Height Eccent: Value - Defines skew offset in the direction of the Height of the ellipse. The top is
therefore moved away from alignment with the bottom so that top and bottom are no longer inline.
This does not affect the ability to unfold the ellipse and get a perfect result without twisting..
Radial Inc: Angle - This defines the angular increment at which radial lines are generated and
shown in the view.
Finite Inc: Angle - This defines the angular increment at which data lines are generated. These
are not shown but the increment should be small because they can affect the accuracy of the
resulting pattern slightly.
End Parameters
The following parameters are available on each end of the oval - End-1 and End-2:
Width: Value - The width is the distance between the two oval end radius centers.
Radius: Value - The radius of the ends of the oval.
Arc: Value - The radius of the arc side of the oval.
In the Asymmetric case the parameters Radius and Arc are replaced with Radius-1, Radius-2 and Arc-1, Arc-2 to allow all four sides of the oval to be defined separately.
Scale: Value - The proportional scale of the end of the oval compared to the other end.
