In this lesson, we'll create a circular toolpath pattern. After completing this lesson, you'll be able to create a roughing and finishing contour toolpath and use Pattern to create multiple instances of a toolpath. In Fusion 360, we want to carry on with our optical pickup. At this point, we're going to move on to cutting these small openings in the bottom of the part. To do that, we're going to carry on using Tool 8 and then we can move on to our chamfer mill and drilling and tapping. For this operation, we can take it a couple different ways. We could try to use a 2D adaptive clearing or we could use a 2D contour. It really depends on the approach that you want to take and the requirements that you have for things like the wall finish. In this instance because of the size of the tool and the geometry, I'm going to use a 2D contour. Again, it's going to be tool number 8, and for the geometry, I'm going to select the bottom of one of these pockets. In the height section, I'm going to use that selected contour but I do want to offset a small negative value of minus 0.05. In the passes section, I do want to add a roughing pass, just a single roughing pass, just to make sure that the final cut is on the wall and that we aren't instantly cutting the wall. We can make this a small value as well such as 0.05 using one step over. We do want to make sure that we're not leaving any stock behind because we do want to finish the bottom. I'm not going to make any adjustments to the linking parameters yet, I want to see what this operation looks like and then I can make that determination. Notice that it does come up with a warning. If we look at the warning, it's telling us that the lead out is dropped due to linking constraints. If we try to simulate this and see what the tool is actually doing, we can see that it's plunging into that hole and then it's working its way out. Now generally, this is not something that you would want to do. If you have a tool such as this quarter-inch end mill that is considered a center cutting tool, then that's something that you can use for drilling and plunging into holes, you wouldn't want to use it at that speed, however. Another option that we have is to modify our 2D contour, go into our linking parameters, I'm going to turn off my lead in for right now and I'm going to leave my lead out but I'm going to reduce it down to 0.02 and then I want to turn on ramp. Turning on the ramp will allow it to ramp down into that contour, and notice that we no longer have that warning. However, the ramp is starting extremely high on the part, this means that we're going to be spending a lot of time before we ever get close to that part. This means that I want to adjust the height and the stock top is just too high away from the part. We're going to use a selection, and I'm going to select the top face of the inside of this pocket. The reason that I want to do that is because everything else has been machined and I know the tool is coming straight down. Now that we have this, let's go ahead and simulate this one operation. Once again, I'm going to play but now as it gets closer, it starts to do that ramped entry based on our contour. Let's speed it up a little bit. Then once it does that initial roughing pass, it's going to do the final finishing pass. You still see some blue on the corner and that's because the chamfer is still there and we have to go back and clear that out. Now that we have this operation, I'm going to select it and create a pattern. To do this, we're going to go into our setup folder and select New Pattern. This new pattern can be based on a linear, a mirror, a duplication, a component pattern, or even a circular pattern which is what we're going to use in this case. Notice that the component pattern can be pretty helpful if you're using some feature-based patterns. Next we need to select the axis. In this case, I'm just going to grab a circular reference on the model. Now we need to decide how many of these instances we have. Notice that as we increase these, it's going to start to fill in all of those positions. We're going to use the equal spacing and we're also going to keep the original operation. I do want to note this drop-down that allows us to order by tool or operation, which means that if we had done the chamfer operation, we could go ahead and pattern both at the same time. This gives us our first circular pattern, and let's go ahead and simulate that to make sure that everything's working properly. Once again, I'm going to speed this up and play through but we should see that ramped entry, then finish one pocket and move on to the next one. Once again, the 2D contour is not the only operation that we could use in this case, we could use an adaptive clearing or a pocket operation, any of these are going to be fine. A lot of cases, they're actually going to have very similar results. In this case, 2D pocket operation and the 2D contour are going to be nearly identical. The controls inside the operation are a little different but for the most part, the end result is going to be pretty close. What I want to do from here is make one more adjustment to that original operation, that 2D contour, and if I go to Edit tool and I go to my blinking parameters, notice that with the heights, we can change the high feed rate mode. Right now it's preserving the rapid movements, but we can always use a high feed between and we can allow that rapid retract. We also have a Keep Tool Down option and then we have this Stay-Down Distance, which will determine how far it has to travel before it actually wants to ramp up to that clearance. I'm going to set that and then I'm going to take a look at the updated pattern. Because this is a pattern, that setting is not keeping between each of the motions. However, if we were to just edit this contour, if we were to come in and make a manual adjustment to our selection and grab another edge, for example. If we use this secondary edge, what we would see is that it keeps the tool down a little bit better than making that adjustment. I'm going to go back and I'm going to make an edit and remove that second contour because I really wanted to use the pattern but I just want to make a note that some of these options such as keeping the tool down really only apply when it's inside of that single, in this case, 2D contour, whereas when we're using the circular pattern, it's going to come back up to those initial settings every time. From here, I'm going to make sure that I do save this before moving on to our next step. I'm going to leave my lead out, but I want to reduce it to 0.02. If I go to Edit tool and I go to my linking perimeters.
