If a piece has an internal line which goes from edge to edge, you can use that line to slice the piece. Once you have sliced a piece, you can configure the seam allowance for each edge.
To slice a piece:
In the 2D window, draw the line you want to use for the slice. Ensure it goes from edge to edge. You may find this easier if you select Snap to Edge on the Horizontal contextual menu. For more information, refer to To draw a straight line:.
If you want to draw a line starting on the edge of a piece, you must ensure Edit Points is not selected on the Horizontal contextual menu.
The following image shows a line being drawn on a piece, in preparation for the piece to be sliced.
On the Main toolbar, click Select.
On the Horizontal contextual menu, ensure Internal is selected.
In the 2D window, select the line you want to use for the slice.
Go to the Context view, in the Actions section.
The piece is sliced along the line, forming two pieces.
The following image shows a piece being sliced.
Slicing a piece cuts the piece in two along the selected line. If there is more than one line inside the piece, you can use these lines to divide the piece into multiple pieces. For more information, see Slicing a Piece.
In one piece, select the line along which the slice has been made.
In the Context view, go to the Actions section, and click Seam Allowance.
Either type in the required seam allowance, or drag the seam allowance point, as required.
Repeat steps 8-9 for the other seam edge.