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Hi there. This video series will cover the process of cutting what appears to be a complicated helical screw, but in reality, it's a quick and easy process. Since we've covered most of the core operations in the more prismatic video series, we generally know what we're doing regarding this. There's nothing particularly unusual about any of it.

We've already dealt with rotary transformations, and most of the operations beyond that are slight modifications of operations we've historically dealt with anyway. So let's take a look at roughing this out, shall we? You'll see that this is basically set up as an already partially machined part. I'm assuming this has come out of a turning center somewhere, and we've been tasked with milling out these veins here to create a proper helical screw.

So what are we going to do? We'll take a look at the roughing options we have. Under the operations menu, we have our standard 3D entry roughing options. We also have options like roughing water lines.

In this case, I'm going to suggest that rotary roughing is probably our best bet because, in truth, the shape looks more complicated than it actually is. It's not that difficult for a CAM program to handle. If we click on rotary roughing now, conveniently, it's already selected the tool we intended to use. The things we need to define now are really not super complicated.

We'll take a look at job assignment. The top level and bottom level are relative to the surface of the cylinder. So that's our top level, and this will be our bottom level. The main thing we need to focus on is the strategy approach.

We're going to go with a circular trajectory form and define the minimum and maximum axial positions. If we click on these, switch to millimeters, I'll grab this plane here and move it up to the edge, which is now at 11 millimeters. That's because we don't need to do anything to this part, and we won't need to do anything to this section either. For the maximum axial position, we'll select millimeters again, and I don't know why it's jumped 10 millimeters there; it's a bit odd.

We'll drag that one, select it, and drag it across to here, which is 95 millimeters. That should realistically cover the range of access we need. The next thing we're going to do is, since this is a roughing pass, we'll go to parameters and define the amount of remaining stock because we don't want to take this all the way down to the bottom. I'm going to set 0.

5 millimeters radial and 0. 5 millimeters axial, why not? I'm also going to loosen the tolerance a little to 0. 1 millimeter because it makes it quicker and easier to calculate.

At this point, we've covered most of what we need to. I think we can probably proceed with generating the toolpath. Let's see what it produces, and as we can see here, there's not really much to observe. It doesn't look like there's a lot going on, which isn't strictly accurate.

There is, but we haven't defined step down or anything, and the assumption is usually that it's going to go at 100% right off the bat, which is not quite accurate. Let's go to strategy; the depth step is currently set at 100%, so I suggest we reduce that to 20% and then regenerate the toolpath. Not only will that make things a bit clearer as to what's happening, but it should also give us a slightly better finish. We've done that, and I'm generally happy with how it looks.

I think we should probably simulate now to see how things turn out and ensure there are no obvious crashes. If we jump over to simulation, we'll slow this down a bit to examine how it progresses, and let's click run. So far, it's realistically behaving exactly as we'd expect. There's nothing overly drastic happening there.

We can see a slight offset from each of these veins, which is what we want. I'm content to say we can probably speed that up and see how it looks. Let's let that run through, and as we can see, it's moving across the entire part in a circular manner, maintaining the same level of cut each time, which is good. It gives you the chance to hit the E-stop button if anything goes horribly wrong without having ruined the entire part.

Let's be honest; we've all been there. It's that scary moment when you think everything's right, and then suddenly reality proves otherwise. As we can see here, we're actually getting quite a nice scalloped finish on this. For a creative piece, that'll actually be quite pretty, but realistically, for what we need, it's largely irrelevant.

However, as we can see, this is now roughing down quite nicely and bringing us fairly close to the shape we want this to be finalized as. This means our subsequent passes won't require particularly heavy cuts, nor will there be a lot of complicated planning work needed for them. I'm quite happy with that. We can take a quick look at the Verify Compare.

We can see that we're still well outside the plus minus 0. 2 territory here. But if we increase that to plus one and set this to plus 0. 5, we can see that generally, we're looking pretty close to what we actually need from this.

Excuse me. With that, I'm content to let this be and bring this to our next video in the series, which will cover the surfaces of these particular larger areas of the helix of this screw. I'll see you in the next video.