Drawing Freehand Curve on Surface in Siemens NX

You can draw freehand curves on the nonplanar surfaces in Siemens NX modeling. The model face works as a sketch zone and the curves that you draw stick on the selected surface. 

You can divide faces by using these curves. These divided faces can be used to thicken, extrude, or assign different colors.

To draw free curves on surfaces:

1. Start the “Draw Shape” command
   1. Curve Ribbon Bar => Advanced Group => Draw Shape
      
   2. Menu => Insert Curve => Draw Shape
2. The “Drawing Base” command dialog box will open.
   
3. Select a face to create freehand curves on it.
4. Click the middle mouse button. (Also you can click on the “OK” button on the dialog box.)
5. The Draw Shape Task environment will open and the ribbon bar will change as the figure below.
6. Some of the specific command functions in the Draw Shape Task environment:
   1. Draw Stroke; draw stroked curves. You can not use the “Trim”, “Extend”, or “Offset Curve” commands on the curves created by the “Draw Stroke” command
   2. Draw Curve; creates smoother curves on the drawing base.
   3. Start Symmetry Mode: Creates symmetry curves through a defined plane as shown in the figure
   4. Finish: Exits the Draw Shape Task environment and applies curves on the base surface.