Sketching introduction

- [Voiceover] As we begin to learn about sketching, it's important to step back and think about why we're sketching in the first place. It's important to understand because every sketch is linked to part modeling in some way, shape, or form. The whole purpose of sketching is to create a 2D shape that can have a 3D modeling action applied to it. This is the repetitive process of actually sculpting geometry to the final part shape. Let me show you what I mean. I'm going to start by clicking New Part in the dashboard, and I get the default part file template.

I'm going to start by right-clicking and selecting New Sketch. And you don't have to understand all these steps. We'll cover each of these in detail as we move on. I really just want to talk about the overall concept, so you can just sit back and pay attention and understand the connection between sketching and part modeling before you continue. I'm going to select a 2D flat plane in order to begin sketching. I'm going to start out by right-clicking and selecting Two Point Rectangle, and I'm gonna lock it to the origin point which is projected automatically.

And I'm gonna create a rectangle, I'm not even gonna put dimensions on it, and I'm gonna finish that sketch. I'm now ready to apply a 3D modeling action to this rectangle. I'm going to right-click and selected Extrude. This is the most basic and probably most used 3D modeling action. When I select Extrude, you can see that the single shape that we had is automatically selected and depth is added. By clicking OK, our part's been created. It's not the most interesting part, but it is a part nonetheless. And we're now ready to continue with our sketching. We're gonna repeat that process again, but this time, when we select New Sketch, instead of the origin plane being presented, we can select a face on the model that's flat and use that as our sketching surface.

I'm gonna repeat that process we did in the first step by right-clicking and selecting Two Point Rectangle, hovering over the edge, which is automatically projected for me, and creating a rectangle in the center. Now that we've finished creating that rectangular shape, we can finish the sketch again. This time, when we right-click and select Extrude, the one closed profile we had was selected and, by default, material is added. We can use the Heads Up Display to change the direction of the cut and remove material. There's also many other options, Distance, To face and body.

Let's set Through All. We'll look at these as we get into part modeling. But, if we select OK, you can see I've created a basic U-channel. Now it's important to know that there's another way to do this as well. I'm gonna go ahead and create a new part file and repeat that process one more time, but this time, rather than creating just a single rectangle, I'm gonna create both rectangles in the single sketch. I'm gonna stay in the Rectangle command and draw the other rectangle that creates the U-channel. This time, I'm gonna finish the sketch, and I'm gonna right-click and select Extrude again.

But this time, rather than a single profile being selected, Inventor wants us to select the shape that we want to extrude. You can see here, we have created essentially two closed loops. We've created the U-channel shape, and the rectangular center shape. I'm going to select the U-channel shape and depth is automatically added to it. If we select OK, you can see that we've created essentially the exact same shape, or a very similar shape, to the one we created in the previous step. But, we did it in a single step, by creating both sketch pieces in a single sketch entity.

Now I'm gonna go ahead and undo that extrusion. Now that you understand how the sketch becomes a 3D solid, we can look at other modeling actions. That same 2D shape, if a revolve action is applied, becomes a completely different shape. We'll go ahead and select the U-channel shape again. But in the Revolve command, unlike the Extrude, we also have the ability to select an axis to revolve around. I'm going to go ahead and switch to the axis and select the bottom line. Here you can see we get a revolved...

That kind of looks like a pulley, maybe. But the point is if I were to cancel this and repeat that process, this time selecting Revolve, selecting the U-channel shape, but this time rather than selecting the bottom edge, selecting the vertical edge on the side, and we get a completely different shape, even with selecting different axes of revolution in the Revolve command. So it's important to understand that not only are 2D sketches going to have a 3D modeling action applied, but each of those modeling actions may have different settings that will allow you to create completely different shapes, allowing you to create just about anything you could dream of.