T-FLEX Parametric CAD. Fundamentals. 2D Design

CIRCLES
Circles
Circles in T-FLEX CAD are constructed similarly to lines, that is, by defining their geometrical relations
with other construction entities. Examples of such relations include placement of the circle center at a node,
tangency to a line, tangency to a circle, passing through a node, concentricity with another circle, symmetry
to another circle.
The T-FLEX CAD circles can be divided into two main groups:
- circles, whose radius can be assigned a number (for example, a circle with the center placed at a node,
or a circle tangent to two non-parallel lines);
- circles, whose placement and radius are defined by construction (for example, a circle passing through
three given nodes).
If a circle has a numerical parameter (the radius), then the parameter can be defined by a constant, a variable
or an expression. To assign the numerical parameter, one can use the property window. The circles are
created in the command “C: Construct Circle”. The relations defined at the time of circle construction can
be modified in the command “EC: Edit Construction” in a similar to line way of handling.
Circle Construction Examples
Before discussing all capabilities of the command “C: Construct Circle”, let’s consider examples of
constructing most common types of circles. Additionally, the command “L: Construct Line” will be used
in constructions. This command was described in the previous chapter.
Enter the command “L: Construct Line”. Select the option , represented in the automenu by the icon
. Move the cursor over the center of the graphic window and click . This creates two lines, a vertical
and a horizontal one, and a node at the intersection. After that, enter the command “C: Construct Circle”.
Keyboard Textual Menu Icon
“Construct|Circle”
Move the cursor to the just created node and click . Thus you define the circle
center. Internally, the system stores the relation between the circle center and the
node. The node will be highlighted, and a circle will start rubberbanding after the
cursor. Meanwhile, the radius of this circle will be dynamically updating on the status
bar (“R=...”).
Clicking completes construction of the circle with the current radius.
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