Week 8 - Challenge 2 - Base Bracket Design
Aim: To create the tooling axis for the given Class-A surface of the Base Bracket and create a solid part along with Class-B and Class-C surface.
Procedure: The input model for the draft analysis is the class-A surface given by the class-A designers as shown below:
Fig. 1: Base Bracket Class-A Surface
Considering the shape of the given path for initially we will define a dummy tooling axis and follow the bisecting method to generate the actual tooling axis. There is a hole which we need to clear using a Core, the first step is to create a point at the centre of this hole from where the tooling axis might pass. Create a point using the point definition and create a line using line definition and point and direction option inside it. This represents the dummy tooling axis for the component.
The tooling axis is expected to be in the Z direction and will be defined using the bisecting method. So, a line is drawn in Z direction and named as a Dummy Tooling Axis.
To make a tooling axis using the bisecting method, we need to have axis in X and Y direction and bisect those to get axis in the Z direction. To draw the tooling axis, we use the Intersect Method. In the Generative Shape Design Workbench, use the Intersect tool to get the intersection between the plane parallel to YZ plane and passing through the center of the hole, and the Base Bracket. It is shown below:
Fig. 2: Intersect of base bracket and plane parallel to the YZ plane
There are 2 faces which could potentially cause trouble during ejection and we need to check whether the draft given to these surfaces is adequate or not. Using the line definition tool, draw two lines as shown below and draw a bisecting line. This bisecting line is named as the Tooling axis.
Fig. 3: Lines representing the drafted faces.
Fig. 4: Bisecting lines to get the tooling axis
This tooling axis and the Base Bracket need to be accessed multiple times and hence, need to be published. Go to Tools>Publication. These will be published in the feature tree.
Next step is to perform the draft analysis of the part with reference to the Tooling Axis. Go to Insert>Analysis>Feature Draft Analysis. Make sure that the View Mode Customization is set to the Material Mode as shown below:
Fig. 5: View Mode Customization
In the draft analysis toolbar shown below, insert the axis system from the Direction tab and place it over the Tooling Axis such that the ’w’ of the compass is aligned to the tooling axis. Lock the compass in place.
Fig. 6: Draft Analysis Toolbar
Another tool box in the Draft Analysis represents the colour coding of the draft angle of the faces from the
Tooling Axis or the Compass placement. It is shown below:
Fig. 7: Draft Analysis Toolbar
If the angle of a surface is less than the 0deg in this picture, the face will be represented by Blue colour. If the angle of the surface is between the two values shown in the figure, the face is represented in the Red colour and if the value is greater than the highest value, it is represented in Green colour.
After opening this toolbar, click anywhere on the Fan Cover surface. The Draft analysis is shown below:
Fig. 8: Draft Analysis of Base Bracket
Since the faces are angled at more than 3 degrees, they are shown in Green colour. Click on the 2nd icon under the Display menu and hover over the face, it will display actual value of the draft as shown above.
To make a Class-B surface, follow the steps for every individual surface:
Select the surface and use Extract, Untrim, Extrapolate, Trim and Offset commands to make a surface profile similar to the Class-A surface as shown below:
Fig. 9: Class B surface creation
To create a Class-C surface, use the Sweep command to sweep the boundary of the Class-A surface along the tooling axis and Trim the surface together to get a closed surface. In the Part Design, use the Close Surface command to make a solid part and save. The orientation of the part is shown below along with the feature tree:
Fig. 10: Front View
Fig. 11: Top view
Fig. 12: Right View
Fig. 13: Isometric View
The feature tree is shown below:
