In the Stretch section there are two useful tools for stretching meshes in various ways. 

Stretch

One of the tools that you will probably use the most is the Stretch tool. You can stretch separate meshes, for example making a handle longer.

Automatic cutplanes are inserted to maintain symmetry during stretch, but you can manually add your own cutplanes.

To stretch a mesh, follow these steps:

1. Click the Make editable button and the click the component that you wish to modify. The component turns yellow and is now editable:
   
   
2. Click anywhere in the drawing area to deselect the component.
3. Make sure that the Single mesh select button is selected.
4. Click to select the mesh or meshes that you want to stretch. You can select multiple meshes by pressing down the Ctrl key and clicking each mesh. Selected meshes turn yellow, like the two pull handles in our example:
   
   
5. Click the Stretch button.
6. Move the mouse pointer to the drawing area in either the 2D view or the 3D view. The mouse pointer snaps to the selected mesh and CET uses a red indication to show where you can stretch. An input box with the following options is displayed:
   
   • Length / Width / Height: The overall length, width, or height.
   • Length change / Width change / Height change: How the length/width/height is changing.
   • Auto depth planes: How many auto planes are activated, for symmetrical scaling.
   • Center: Check box to stretch from both sides of center. If you do not turn on any Auto planes or insert any cutplanes, the component will scale evenly. We have used this feature in our example with the pull handles.
   • Split mesh: See Split Mesh.
7. Click once where you want to make the stretch.
8. Move the mouse pointer without pressing down the mouse button, or use the properties box to control the results, to stretch the component to the desired size:
   
   
9. Click once to complete the stretch. The mesh has now been stretched, as shown with the pull handles in our example:
   
   
10. A new red indication is now attached to the mouse pointer letting you repeat steps 6-9.
11. When you are done, press the Esc key on your keyboard or move the mouse pointer outside the drawing area to release the Stretch tool.

Cutplanes

A cutplane works as a divider between different planes.

This could be useful if you, for example, want to alter a bookcase by adding some space between the shelves while keeping the shelf thickness. Or, as in the example below, when you want to heighten a storage tower while keeping the drawers the same size.

To insert a cutplane, follow these steps:

1. Click the Make editable button and click the component that you wish to modify. The component is now editable.
2. Make sure that the Single mesh select button is selected.
3. Click to select the mesh or meshes that you want to add a cutplane to. You can select multiple meshes by pressing down the Ctrl key and clicking each mesh. Selected meshes turn yellow.
4. Click the Cutplanes button.
5. Move the mouse pointer to the drawing area in either the 2D view or the 3D view. The mouse pointer snaps to the selected mesh, and a blue cutplane is visible.
6. Move the mouse pointer over the mesh to get the cutplane in the right position. An properties box appears where you can select X, Y or Z direction. You can also use the space key on your keyboard to select the direction. You can also use the Remove button in the input box to remove an existing cutplane.
   
   
7. Click once to add the cutplane. A new cutplane is attached to the mouse pointer. Keep adding cutplanes until you are satisfied.
8. When you are done, press the Esc key on your keyboard or move the mouse pointer outside the drawing area to release the Cutplanes tool.
9. Stretch the mesh as needed.