In this episode, I will present how you can analyze CAD model of the part before you start creating tool paths.
First, I want to look for undercuts. As always with NX, we have several ways to do this. For example, we could use Draft Analysis. But I will use Slope Analysis instead. In this dialog I should select faces which I want to analyze and choose vector which defines “top” direction. In Data Range section I will set +1 and -1 degrees as range for color map. This way I can easily spot first undercut.
If we will use wider range for color map, we can analyze also steepness of faces. It is worth to experiment with this. If you click at the face, it will add a label which will be showing you angle in the chosen point. Label will stay visible even after you close this dialog. To return to normal display of the part, just change shading type. And to display colors from last analyze, choose Face Analysis like this.
Next option which I would like to show lets you find what is the smallest radius value and where it is at the part. This option is called simply Minimum Radius. And after selecting all faces it will display result in Information Window and small vectors will show you where is this radius at the model.
I will show you now two options which are very handy during CAM programming. First one is Geometric Properties. I already have shortcut created. In one of my previous videos I was showing how you can add shortcuts.
After starting Geometric Properties option, just move your cursor around faces which you would like to get information about. Watch Minimum Radius value. If it is positive, radius is concave. Negative value means convex radius. If it says “infinite”, face if flat.
If you want to get even more information about face, select single face and choose Object Information. It will open Information Window with details of this face. Most interesting parameter for me is Surface Type. It tells me if face is planar or cylindrical – this information is useful when you are wondering how to machine this face. Other types can be: toroidal, blend, b-surface, conical, spherical and so on.
Another useful option lets us find and distinguish small concave radiuses. It makes it easier to choose proper tools later.It is called Concave Faces. As you can see, for each radius size we can apply separate color. And it’s not everything yet. We can also add labels. Colors and labels stays visible even after we close Concave Faces tool.
What I showed today are just few example ways of analyzing model of the part. I’m sure most of you are using also other methods, so feel free to share it in comments below.