Swapping the Skin

This task shows you how to swap geometry from an engineering surface to a manufacturing surface, using a normal projection.

Available in Composites Design for Manufacturing (CPM).

Skin swapping can be performed only on tangency continuous shells.
When a Swapping feature already exists, you can not create a second one, but you can edit it if modifications are required.
Butt Splice Zones are taken into account by the Skin Swapping command if you select the Stacking node.
If the Skin Swapping was applied to elements under the staking, you can generate a Skin Swapping feature for the Butt Splice Zones by selecting either a zone or its group. In this case a Skin Swapping feature will be added at the end of the Composites Geometry of the corresponding elements.

Open the SKinSwapping1.CATPart document.

Click Swapping .

Select the feature where you want to insert the swapping in the specification tree.
It can be a ply, a sequence, a group of plies, cut-pieces, an edge of part or a stacking.
In our scenario, we selected the Stacking (manufacturing).
The Skin swapping dialog box is displayed.
The engineering surface to be swapped is already selected in the Swap frame (Extrude.1).

As Edge Of Part and Swapping are not symmetric operations, the skin swapping of an EOP created from plies will not be strictly equal to the EOP created from swapped plies.

Now select the manufacturing surface to be swapped with Extrude.1:
Select Offset.1 in Body.1.
Its name is displayed in the dialog box in the With column.

The draping direction is displayed in the 3D geometry.

You can click Invert to reverse the draping direction and be consistent with the direction defined in the engineering plies.

Select the Swapping mode (we have kept Projection):

By default, the Swapping mode is set to Projection: the command will perform a projection perpendicular to the destination surface. The projection of the engineering geometry of the ply from the engineering surface to the manufacturing surface is only performed on the nearest portion of the manufacturing shell.
If you select Elevation, the command will perform a projection perpendicular to the origin surface.

If you have selected a stacking, a plies group or a sequence, the Invert stacking order check box is available. Select this check box to invert the order of plies during the swapping (we have not selected this check box):

if you have selected a stacking:
- the order of plies groups is inverted (the first becomes the last, the second becomes first before last, etc.),
- then, in each plies group, the order of sequences is inverted in the same way,
- then in each sequence, the order of the plies is inverted in the same way.
if you have selected a plies group:
- the order of sequences is inverted (the first becomes the last, the second becomes first before last, etc.),
- then in each sequence, the order of the plies is inverted in the same way.
if you have selected a sequence:
- the order of plies is inverted (the first becomes the last, the second becomes first before last, etc.).

Click OK in the Skin swapping dialog box.
The engineering geometry is transferred onto the manufacturing surface.
It is put in the No show space on the engineering surface.

In the specification tree, the Swapping feature (identified as Swapping.xxx) is displayed under each ply.

You can edit any swapping element in order to change the manufacturing surface.

Double-click Swapping.1 element in the specification tree.
The Skin Swapping dialog box is displayed.
Select the new manufacturing surface.
Click OK to perform the modification.
Only the ply referencing the feature is modified.

You can also change the manufacturing surface by editing a plies group.

Double-click the Plies Group.1 feature in the specification tree.
The Plies group definition dialog box is displayed.
Click Change and select the new manufacturing surface.
Click OK to perform the modification.