Week 8 - Challenge 1 - Base Bracket Design

Objective:

The main objective of this challenge is to create the Base Bracket Plastic component through the above-given Class-A surface, by giving the 'Tooling axis' and 'Draft analysis' to the class-A surface of the base bracket.

TOOLING AXIS:

We should keenly observe and study the class A surface to create the 'Tooling Axis' for the component, for the above-given base bracket Z-axis is the best suitable tooling axis. Initially, I created a dummy tooling axis on Z-axis by considering the reference point created in the middle of the circle.

DRAFT ANALYSIS:

To perform draft analysis, click on Insert >>Analysis >> Feature Draft Analysis

Once the draft analysis toolbar is opened, go to the display block and select the 'Analysis under the running point' command to check the angle for different sides (ribs and inclined plane angles) on the class A surface. The color scale on the bottom visualizes, whether the draft angle meets the requirements or not (3 deg) by indicating the colors Green, Blue and Red. Once the draft angle analysis was done, we need to align and fix the compass to the tooling axis of the class A surface.

CLASS B SURFACE:

To create the class B surface, I considered the entire surface has 3 parts 'Rib-1, Rib-2, and Base surface'. If we directly offset the class A surface, fillets may lead to cause an error, to avoid the errors we need to extract the surfaces and untrim the extracted surfaces and extrapolate those untrimmed surfaces with point continuity. Now trim those extrapolated surfaces to the required shape. And finally, fillets were given to the final trim.

Class C Surface:

It is the combination of Class A, Class B and Class C surfaces. To create a class C surface, I used the sweep command by considering the outer boundary of the class A surface. In the sweep command, go to the 'line' command in the 'profile' block and the subtype is 'with draft direction'. Now select the outer boundary and tooling axis, give 3 deg in the angle (the draft angle for a plastic component is 0.5 to 3 deg) and select the direction to sweep, in this condition the class B surface is under the class A surface so select the inside down arrow to sweep. The same procedure is repeated for the two circles on the class A surface.

Final Trim (closed body):

Now I joined all the swept surfaces by using the 'join' command and then I trimmed the Class A, Class B and Class C surfaces to make a closed surface, to make a Solid body.

DRAFT ANALYSIS:

To align and fix the compass to the tooling axis, go to the Direction block in the draft analysis toolbar and click on the 'Use the compass to define the new current draft direction option (or just click on the compass symbol). Now bring the compass to the surface and align it to the tooling axis of the class A surface and click on the lock symbol beside the compass in the direction block. Once we click on 'ok' on the draft analysis toolbar, we can finish the draft analysis process.

INTRODUCTION:

CLASS-A SURFACE: a surface made by the designer which is given as an input to the plastic modeler to work on. It is aesthetic surface and the outer most surface.

CLASS-B SURFACE: a surface below a certain thickness from the class-A surface is class-B surface. This is the surface that contains engineering aspects of a model.

CLASS-C SURFACE: a surface that joins class-A and class-B surfaces is class-C surface.

METHODOLOGY:

In this model we have focused on the following things:

1. Tooling axis
2. Draft analysis
3. Class-B surface
4. Class-C surface
5. Making a solid model from surface.

Following tools were used to reach the final step:

1. Extract
2. Un-trim
3. Trim
4. Extrapolate
5. Offset
6. Edge fillet
7. Boundary
8. Sweep
9. Join
10. Close (part design)