Creating a Shell

This task explains creation of a shell. A shell is the plate that goes over the hull and is usually the first step you need to take.
In most cases one you will have more than one shell for your hull. In the example below it is assumed that two shells will be created - starboard and port.

1. Create an SFD system under the root product (see Organizing Your Document), rename it if necessary. Select the CATPart that is created under the system in the specifications tree and go Start - Equipment & Systems - Structure Discipline - Structure Functional Object Design.  The image below shows the starboard hull with shell placed on it.



Click the Plate button to display the Plate dialog box. The entries are explained below:

  3. Category: Click on the down arrow to display the entries - they will include the last 10 entries that you selected. If Shell is not displayed then select More to display the Class Browser and make your selection from that list.
  4. Name: The application can assign a name to the object you are creating using the object naming function if you check the Automatic checkbox. If you want to assign your own name then uncheck the box and enter a name.
  5. Support: Select the hull (you can select it in the specifications tree) as the support for the shell -  once you select a support the shell is placed (in preview mode). Your selection displays in the Support field. The image below shows the specifications tree structure and the hull (with the shell preview).

  6. Limits: This function trims the excess plate.

Under Offset, you can define the offset value of each plate limit. A positive value adds material. A negative value removes material. Additionally, limit tags display in your 3-D session to assist with plate limit management.

If, as in this example, you are creating two shells for the hull, then you can use a longitudinal plane as the limiting object. To do this, right click in the Limits field and select Select Reference Planes to display the Plane Systems dialog box. Select Long as the System and Sub-system, and select LONG.0 in the Select Planes pane. See Using Reference Plane Browser for more information.

Click OK to trim the shell - in the image below the user is intending to trim the starboard side, leaving the port shell. If you want to trim the other half then click the Switch Side button, as explained below.

The Remove button allows you to delete a limit.

The Switch Side button lets you toggle between limited sides. In the image below the user has clicked the Switch Sides button to toggle sides. You can also switch sides by selecting the same limit again.

  7. Click OK when you have finished.