By inserting a Workplane you can define a new workplane for a certain mesh. You can, for example, insert a diagonal plane as a complement to the horizontal and vertical planes. Essentially, you are changing the X, Y, and Z axes around which edits are made.

To insert a workplane, follow these steps:

1. Click the Make editable button and click the component that you wish to modify. The component is now editable.
2. Click the appropriate Workplane button; there is a 2D tool that operates on the X and Y planes, and a 3D tool that operates on the X, Y, and Z planes.
3. Move the cursor to the drawing area. The cursor snaps to different places on the component, and a blue workplane is visible in 3D.

4. For the 2D tool, select two points on the component that you want to match your workplane to. First, click once for X, adjust the arrows to the direction of rotation, then click once for Y.
   
   
   OR
   
   For the 3D tool, select three points on the component tab that you want to match your workplane to. Click once for X, Y, and Z.