T-FLEX Parametric CAD. Fundamentals. 2D Design

Lines
These rules result from the use of the coordinate system in T-FLEX CAD. That helps keeping the once set
relations between construction entities under any modifications of the parameter values.
Note that the “-” sign may be preset by the system before the parameter input box in the property window.
The system is monitoring the rubberbanded line position with respect to the reference parallel line. When the
new line is rubberbanded in the area of negative offsets, the negative sign is automatically set, and the user
needs to enter only the absolute distance.
As an alternative to entering a specific distance value, one can use variables. The name of a variable is
defined as a US ASCII string of no more than 10 characters. The names are case-sensitive, therefore, for
example, the two names “Width” and “width” are different. Let’s assign the distance between the two
lines a variable “W”.
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A dialog box will come up then, for defining the value of the
variable. The variable being created can be flagged as
“External”. The variable can have a positive or negative value, or
assume the value of another variable or mathematical expression
based on other variables. Let’s enter the value “50” for the
variable.
If we flagged the variable as “External”, then in future it will be
accessible for assigning values from outside the document.
Such situations include, for example, use of external applications, or assigning a value from an assembly
document upon inserting the present drawing as a fragment. In our particular example, the variable is not
required to be external.
Once the value has been assigned to the variable, a line is created, parallel to
the reference one, at the distance of 50 units on the left-hand side of the
reference.
Now, one can verify the just defined relation between the lines. Enter the
50
command “V: Edit Variables”:
Keyboard Textual Menu Icon
“Parameters|Variables”
The Variable editor dialog box will come up on the screen. The only variable displayed in the dialog box will
be the just created “W”, with the value “50”. The Variable editor has four fields (columns): “Name”,
“Expression”, “Value” and “Comment”. Since we entered a numerical value for the variable, the “Value”
and “Expression” readings are the same.
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