Add or remove symmetry. In this video, we'll add and remove symmetry. In Fusion 360, we want to carry on with our box primitive. We want to start understanding how we can add and remove symmetry from a design. We're going to do a quick test, select this face and select "Modify" edit form. We're going to begin pulling the face up, moving it around, scaling it and rotating it, and seeing how the form changes. Let's hit Cancel and Control Z or Command Z to undo or use the undo options in the upper section of Fusion 360. Next, we're going to go into symmetry and take a look at all of our options. We have Mirror Internal, Circular Internal, Mirror Duplicate, Circular Duplicate, Clear Symmetry, and Isolate Symmetry. For our example, since we're dealing with a single body, we're going to use Mirror Internal. When we do this, we need to select faces across a mirror plane. As soon as we select those faces, note that it's giving us a green line. We say, okay, we select this face and now go to edit form. As we begin pulling this up, note that it's moving both sides. Each side is moving equally. Because of that symmetry, we only have to select one side and make those adjustments. Now that we've modified this design, let's go ahead and go into symmetry and select "Mirror Internal". You can see if we select across another plane of reference that it's modifying the geometry to make sure that it can maintain that symmetry. There are of course, limitations to this. If the geometry is two different or the number of faces doesn't match, oftentimes it'll fail to create that symmetry. But now, if we select just a single vertex, for example, and use Edit Form, now we're going to be moving this single vertex and it's going to affect change in all four corners. So once again, it's handy to understand how to create the symmetry, especially if the model that you're working with has symmetry across a single or multiple planes. But what happens if you want to undo or remove symmetry? Sometimes your designs will be mostly symmetric, but there'll be cases where you want to remove that symmetry to make some unique adjustments. Under the symmetry section, we have Clear Symmetry and Isolate Symmetry. When we select "Isolate Symmetry", we can select individual faces, and note that it's giving us warnings because the selected operations have symmetry across multiple planes. If we say Okay, and then we try to use Modify edit form. Notice that it's not respecting the symmetry anymore. It's allowing us to make those adjustments to that single face. The symmetry is still listed there. However, we're now saying that we don't want to respect it. If I go back and I unisolate the symmetry, notice that it's not allowing us to bring that symmetry back. It's already broken that reference. We also have the option to clear symmetry altogether. If we select the entire body and we select Clear Symmetry, now we've removed all planes of symmetry from the model. These can always be added back at any time. For example, if I determine that I want these two to be symmetric again, it will bring them back into symmetry, simply by selecting them across that plane. That might not always be the case. So I do make sure that I caution everybody when beginning to use symmetry. Make sure that your designs are truly symmetric. Note that you can create the symmetry after the fact. If you want to work on half of a model, you can do that by simply removing selected faces, making adjustments, and then creating a mirror duplicate. If we use Control or Command to select all those faces and we hit "Delete" on the keyboard, note that it removed everything. But if we clear the symmetry first, and then we select specific faces that we want to get rid of, it's simply going to turn this into a surface body. Now we could make adjustments, manipulate the geometry, and then we can use mirror duplicate to create a copy of it, even if it's along a line of symmetry. For right now, however, let's make sure that we undo and turn this back into a solid box, go back to our Home View, and make sure that we save the design before moving on.
