Spline

The only freeform curved object

Start Line command

Pick a point and move to lower-left corner
Enter 1800 < 157

Pont up and enter 550 < 98

Point down and enter 900 < 96

Command line: Close

Draw panel > Spline Fit

Pick the points from the top lines

Pixk points from the bottom lines

Modify panel > Join

Select both splines

Press Enter to join them into one

Spline Edit

CNC machine not recognize spline object
You need to convert spline to polyline for CNC machine to make the shape

Double-click on the spline

Select convert to Poline

Press Enter for the default precision