T-FLEX Parametric CAD. Fundamentals. 2D Design

Fundamentals. Two-Dimensional Design
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The “Symmetry About Axis X” flag among the function
spline parameters allows mirroring of the created entity
about the X-axis of the function local coordinates. (The
X-axis passes through the two nodes selected at
function spline creation).
If in future this construction line will be subjected to a symmetry transform (for instance, in copying or in
translation), then the state of the flag of the transformed line may be changed by the system automatically.
To construct a spline symmetrical to a given one about an arbitrary line, use the option .
Additional parameters “Scale of Axis X (Y)” allow
changing the scale along each axis of the function local
coordinate system. The coordinate of each point used
in the function creation is multiplied be the specified
scale factor.
The “Change on Transformation” flags, to the right of
the respective axis scale input boxes, allow/disallow
automatic change of scale when subjecting the given
entity to a scaling transform (as in copying or
translation). The cleared flag prohibits automatic
change of the respective scale factor, while the checked
item allows it.
Note that special-type nodes are created at end points of function spline construction entities (as
well as in other curves). These are created by using the option of the node creation command.
Evolvent Creation Example
As an example, let’s create a profile of a cogwheel. First, let’s make all necessary calculations and
constructions: circles, cog size, etc. relating these parameters by variables.
Then, using the “Evolvent” function, specify two points for defining the Х-axis of the evolvent. Besides, the
first point also defines the center of the main circle (rb). Each equation among the function parameters needs