In this lesson, we'll refine the airframe. After completing this lesson, you'll be able to use fillet. The last thing that I want to take care of on this body before we add the additional mounts for camera and the video transmitter, is I want to add a few more fillets. Now there are certain areas in here where we're going to be potentially making some modifications or changes, but the areas that I want to add fillets to are inside of pockets. That's because, again, with the stress risers, the fillets in these pockets are going to help make sure that the stress is smoothly transitioned from one section to the other. So I'm going to start by creating filets on these internal edges here. We're going to hold down the control key. Anytime we want to add a new fillet, let me go ahead and grab these as well. Then we'll come to the other side and we’ll add it in fillets in these areas. And again, any time you have a sharp corner, it’s going to allow for a stress riser. So you want to make sure that you smooth out all these corners as best as possible. We'll go ahead and say okay to that one millimeter fillet. And then we're going to repeat the command and add additional fillets in areas of concern. And I say areas of concern, and the main area that I'm talking about is carrying the stress from the motor mount into the mounting point where we're going to undo our component tray. So we're going to place a fillet on this inside edge, and we're going to put 1 millimeter in there and take a look at what it looks like. So that's a nice, smooth rounded edge. And I can apply that fillet to these other pockets as well. Now there are some instances where the tangency won't be carried automatically, and you'll have to come back and make some manual suctions. And until you do, you'll notice that it won't completely cover that entire area. For instance, in areas like this, there's actually a sharp corner here that we need to account for And you'll notice that this is giving me an error because of this corner. So we're going to cancel this operation, and we're going to make sure that we smooth out this corner. And because this was a mirrored feature, we need to make sure that the one on the other side is taken care of as well. We'll go ahead and we'll add a 1 millimeter fillet in that area, and we'll say okay. So now we can go back and we can add the fillet to these internal edges. And I'm going to use a 1 millimeter fillet for right now. And I like to do this because I want to make sure that the preview is populated. So anytime I need to add a new one, I'll hold on the control key. As soon as I let it go, I should see a preview of that fillet. Control and I'll add this one, and this one as well, which will require me to make some selections going around. And then as soon as I let go of the control key, you can see that's populated. And now we'll try over here. And because we went back and we added that fillet in this small corner here, we now are able to add that fillet. Go ahead and place it on the inside of this region- Place it on the inside edge here. You notice that this one produces an error. It doesn't like to populate this one with a one millimeter fillet. Now if we try 0.5, we can see if this is going to populate, and that works out okay. And the reason that that happens is, again, because of a corner somewhere that has a fillet that doesn't allow the tangency to be carried. But that's okay because a half millimeter will still give us a little bit of an advantage in terms of carrying that stress. So we can see that one carries over as well. Now this is only half of the design on top. We still need to apply the fillets to this other side as well. And if you want to we can apply them to the bottom as well. So there are a lot of edges where we can apply this fillet. And it's my suggestion to you that we go ahead and okay this operation, and you save your file. Because sometimes these fillets can be a little tricky as we go through. At some point you have the potential to lock up fusion, and this happens with any CAD software. Whenever it's calculating fillets on complex geometry, you could just run into that one edge or that one line that produces an error and it'll just sit there and think for a while. So, again, we want to make sure that we okay the operation, we're going to save, and then we're going to create the same half a millimeter fillet on the other side. Once you create these fillets on the other side as well as the bottom, go ahead and save your file so we can move on to the next step.