Week 9 - Project - Master Section Development

Master Section Development

What is Generative Shape Design?

The Generative Shape Design provides an extensive set of tools for creating and modifying mechanical surfaces used in the design of complex shapes or hybrid parts, Its feature-based approach offers a productive and intuitive design environment to capture and reuse design methodologies and specifications. It helps to design advanced shapes based on a combination of wireframes and extensive multiple surfaces, including high-level features with full specification capture and reuse.

What is Draft Analysis?

The Draft Analysis command enables you to detect if the part you drafted will be easily removed, this type of analysis is performed based on color images identifying zones on the analyzed element where the deviation from the draft direction at any point corresponds to specified values.

No parts can be ejected from the tool if it is having a straight 90-degree profile from its base surface, a small draft angle is provided to each area of the component to get easy removal of the component from the tool. The draft analysis technique is used to analyze whether our part model created in cad is manufacturable based on the draft condition applied.

In the molding process, the molded parts have to eject from the die so there are some issues while removing the molded parts it may get sticky with the die, or while removing the chances to get damaged, so we need to set up is the draft angle this draft angle helps the molded part to eject from the die easily.

What is Class A, Class B, Class C Surfaces?

Class-A Surface: Surfaces made by the designer which is given as an input to the plastic modeler to work on, it is aesthetic surface and the outermost surface.

Class-B Surface: Surfaces made below a certain thickness from the Class-A surface is Class-B surface. This is the surface that contains engineering aspects of the model.

Class-C Surface: Surfaces that join Class-A and Class-B surfaces is Class-C surface.

4 Way Locators

In any kind of assembly before fixing the part to the mating we need to fix the position of the part with the respect to the mating part. In these cases, we need to follow some engineering principles in this project we are going to follow the 3-2-1 principle, any part which has to be fixed during the welding or machining process has to be fixed is having 12 degrees of freedom.

Introduction

The B-Pillar is the post between the front and back seat doors of a car, connecting the roof to the body, it can be also defined as the vertical roof support structure located between the front and rear doors on a typical vehicle. It corresponds with the A-pillar located on either side of the windshield at the front of the car and the C pillar which sits on either side of the rear window on a typical sedan car.

Master Section

Master sections are the guides for design requirements that decide the component packaging after technical surfaces such as Styling, Concept, or Class-A). Following is the general workflow that is followed for the design and development of interior and exterior automotive trims in OEMs.

Procedure

1. After importing the model into Catia, check the given Class-A surface for geometry errors, or if the faces are missing create a new face with the multi-section tool available in Catia.
2. To provide the draft for the entire component. The tooling axis has to be created for the core and cavity to be designed in the later stages.
3. From the given master sections, create the tooling axis with the bisecting line option available in the Line tool.
4. The next aim is to create the B surface which has to be created 2mm from the class A surface, which has to be a replica of the class A surface provided, also flanges have to be created on the either ends of the A surface as well as B surface with reference from the master sections given.
5. The general steps followed in creating a surface are by extracting the surfaces without fillets, Antrim, and extrapolate the extracted class A surface if needed and offset the surface to the part thickness given, Next step is to trim or split the surface according to the shape needed.
7. After the B surface is generated, the C surface has to be developed in the Class A surface using the sweep toolbar without any generic change in Class A with a minimum draft angle of 3 degrees. {Note only if the Class C surface is in the direction of the tooling axis}. All the draft angle has to be given outside of the part i.e., the material has to be added rather than cutting it.
8. After the C surface is created along the boundary of class A, join and trim it all together to make it a single surface.
9. Class A and Class C have to be trimmed to form as a single surface and thereafter trim with the above developed Class B surface to get the B pillar part.
10. After which the part is created, check for the boundary if it is closed or not and now change the workbench to part design and create a solid part out of it using the closed volume too
11. After the creation of the closed body, check whether the main tooling is clearing all the parts within the draft given, the draft analysis of the B pillar is given below.

DOG HOUSE WITH LOCATOR AND RIB CREATION

1. For the Rib and Dog house, proper design rules or criteria has to be followed which are given below:
2. After developing the dog house, the inside part will not be drafted with the main tooling axis so that aside from the core axis or lifter axis has to be created and a separate draft has to be given to the interior of the dog house, the four-way locator can be easily developed with the reference from the sketch of master section and extrude with applying thickness to it, with applying proper chamfer, draft and fillet radius, the locator can be created successfully.
3. The draft analysis for the dog house is given below:

4. The rib is created onto the B pillar to impart strength to the main part

All views of the B Pillar

Tree Structure