Existing lips can be easily removed from a sheet metal part. You can specify a number of options that control how the lip is to be deleted, such as the cut plane for the lip and how bend and corner reliefs are to be handled.
You specify the lip to delete by specifying a face on it. From this face, a top or bottom face of the sheet is detected. Creo Elements/Direct Sheet Metal then uses this face to select the bend and the larger side of the part, and the base face follows from this. However, you can always select the base face manually if necessary, to delete the other side of the bend. The direction of the cut plane is always defined by the bend and the base face.
The plane at which the lip is cut from the part can be one of the following:
• Outside: The plane at the intersection of the outer lines of the lip faces in both directions of the bend.
• Inside: The plane at the intersection of the inner lines of the lip faces in both directions of the bend.
See the graphics below for an illustration.
• Bend Start: The plane at which the lip bend begins.
• User def: The cut plane can also be positioned by manually selecting a 3D point.
• Adj Face: If bend reliefs exist, the cut plane can also be positioned at the faces adjacent to the bend relief. (This option is only available if the left and right adjacent faces are in the same plane.)
Visual feedback on the model shows the cut plane. The following graphics illustrate the Outside, Inside and Bend Start cut planes applied to lips at less than and greater than 90 degrees:
Delete Lip (<90 degrees)
Delete Lip (>90 degrees)
If the part contains bend reliefs, these can either be kept or removed after deleting a lip. If they are removed, the side faces are aligned. Likewise, in the case of corner reliefs, you can keep them, remove them, or adjust them to fit for a new lip. The differences between the actions are as follows:
• Keep: The geometry of the relief is kept, but the relief feature is removed.
• Remove: The geometry of the relief is closed, and the relief feature is removed.
• Adjust: This option is available only for corner reliefs, and only when more than three bends meet at one relief; that is, if two bends are left and an existing corner relief needs to be adjusted for the new situation. The action is the same as with Remove, except that for reliefs with more than one bend left, the existing relief is replaced by a new relief of the same type. (This may or may not change the geometry, depending on the part.)
When removing corner reliefs along with a lip, note that the state of the part prior to adding the lip cannot be fully restored. Creo Elements/Direct Sheet Metal attempts to remove or replace existing corner reliefs appropriately according to each situation.
To delete a lip:
1. Click Sheet Metal and then, in the Modify Sheet group, click the arrow next to Lip.
2. Click Delete. The Delete Lip dialog box opens.
3. Click the Lip to delete. The Base Face is automatically selected by the system.
4. If necessary, specify a different base face for the lip.
5. The On Line and Single check boxes are active if the lip is forked, that is, consists of more than one separate bend:
◦ On Line assigns a single feature to all bends of the lip, so that all parts of the lip are deleted.
◦ Single copies the bend feature to the bend of the selected part of the lip; the other part receives its own independent bend feature. In this case, only the selected part of the lip is deleted.
6. Specify the Cut Plane of the selected lip in the Range box, as described above. If you select User def, you must also click a position in the viewport that defines the plane.
7. If necessary, select the Method for dealing with bend reliefs, as described above.
8. If necessary, select the Method for dealing with corner reliefs, as described above.
9. Click Preview to see how the deletion will happen according to the current selections.
10. Click Next to complete the current deletion but keep the menu active, or click to complete the operation.
Lip.
Delete. The Delete Lip dialog box opens.
to complete the operation.