2.0

Drawing Templates
273
n
Type C to select the Close option. This option closes the template surface.
The Close option draws the final segment from the current point back to the
starting point. It is not necessary for all components to be closed (i.e., if they
will be mirrored about the centerline).
n
Type U to erase the last segment drawn. You can repeat the Undo option
until the Draw Template command returns to the starting point.
n
Type X to exit the command.
5 Continue picking points until you have finished drawing the template.
Create the surfaces on the left side of the finish ground reference point for
symmetrical templates. The Define Template command mirrors the surface
about the finished grade reference point. Draw the complete surface as one
continuous polyline for asymmetrical templates.
6 Define the template after you have finished drawing it.
NOTE
When defining a template or subassembly, the outline of each component
must consist of a single 2D polyline for the left side of the template. A
subassembly can consist of only one component. A template can consist of
more than one surface, each one drawn as a separate polyline.
Drawing Normal Surfaces for
Symmetrical Templates
Follow the general procedures for drawing a template surface, keeping in mind
the following points:
n
If a template is symmetrical, both the left and right halves of the template
are assumed to be identical, and are mirrored when you define the template.
Because of this, it is necessary to draw only the surfaces for the left half of
the template. When you define the template, the surfaces on the left half are
mirrored about the vertical plane that passes through the finished ground
reference point.
n
A normal surface that has the opening at the mirror plane (the finish ground
reference point) is mirrored so it becomes a closed surface. An example of
this type of surface is the asphalt surface of a two-lane road.
n
When drawing a normal symmetrical surface, start at the centerline (the
vertical plane of the finished ground reference point) and draw the surface to
the left, in a counter-clockwise direction, until the surface returns to the
centerline.
n
Any normal surface that does not intersect the mirror plane must be drawn
as a closed surface. When you define the symmetrical template, all closed
surfaces are mirrored about the vertical plane that passes through the finish
ground reference point. An example of this type of surface is a curb surface.
n
When drawing a closed surface that does not cross the centerline, start at a
point that is nearest the centerline and draw the surface in a clockwise
direction.