Challenge

Week 11 - Project - A pillar Design with Master Section

DDurgesh Choukiker24 May 2023

AIM :- Create the A Pillar Plastic component through the given Class-A surface and master section and perform Draft analysis.

A PILLAR :- A-Pillars straddle the windshield, B-Pillars are in the middle of the passenger compartment (just behind the front doors) and C-Pillars are those at the rear of the passenger compartment.

MASTER SECTION :- Master sections are the guides for design requirements which decide the component packaging after technical (Styling, Concept or Class-A) surfaces. Creating this master section should need 5 to 6 years of experience. This helps you to decide the feasibility, clearance, the packaging and the fixation strategy before working it on a 3D.

CLASS A SURFACE :- Class A surface is a surface made by the designer specially in automotive design which is the aesthetic part of a body and is given as an input to the plastic designer to work on it.

CLASS B SURFACE :-

After all the validation has been done, the class B surface is created by offsetting the class B surface to a distance of 2.5 mm
After offsetting a large opening in the surfaces is found which is closed with the help of sweep and multi section commands
The class B surface is then extrapolated in parts to trim it along with the class C surface.

CLASS C SURFACE :-

The class C surface which connects the class A and class B surface is created by sweeping the boundary of the class A and using the class A as a reference.
The sweep is divided into several parts in order to avoid complexity
Surfaces which are parallel to the tooling direction are swept with the tooling axis as reference and with a draft angle of 3degrees.

TOOLING AXIS: Tooling axis is the direction in which the core and cavity opens. If we are using proper tooling axis, we can avoid adding side cores thus the cost of manufacturing the component can be reduced.

It is defined as the direction in which the mould/core and cavity open. Selection of the direction of the tooling axis depends on the ease at which components can be easily ejected.

Generally tooling axis is decided from the natural axis of the design, that is, tooling axis is analysed with the x, y and z axis of the system. If the axis doesn’t clear the draft analysis, the next step is to look for the surface in which the drafting axis can be created in such a way that the axis is normal to the surface taken. These are the methods of deciding tooling axis. Bisecting method is the least used method.

BISECTING METHOD: It is a method used to create tooling axis. The sides of the surfaces are chosen in such a way that the edges may affect the tooling axis are taken as the input for the creation of tooling axis. This axis is then created by giving the line type as bisecting line and the inputs as the lines constructed from the edges that affects the tooling axis. This is not frequently used technique for creating tooling axis.

Here, tooling axis is created using the reference from the master section. As there is a doghouse present in the B side, the sides of the doghouse is taken to created the tooling axis. Two lines are drawn from the edges of doghouse and another line is drawn by using the line option as bisecting line, with inputs as these lines. Thus, the line obtained after these inputs is the tooling axis obtained from bisecting method.

DRAFT ANALYSIS :- From draft analysis, we can verify draft angles, examine the angle changes within a face, as well as locate parting lines, injection and ejection surfaces in parts.

It is an important feature in Catia which helps the user to analyse the draft on various surfaces. The draft analysis toolbar provides two modes for analysis of the draft, first is the quick analysis which basically has three colours (green, red, and blue) for analysing on the other hand other option is the full analysis mode which enables a few more details into the draft and is used in the complex components.

ON CLASS A SURFACE :-

ON CLOSE SURFACE :-

ON DOG HOUSE WITHOUT RIBS :-

ON FINAL A PILLAR :-

Creation Of Closed Surface :-

Class A surface and Class C surface is joined.
Now Class B surface is also trimmed with the obtained surface to get the closed surface.
Boundary check is done to check for any open boundaries in the part.
The closed surface then obtained moved to part design and close surface tool is used to obtain the part.

Creation Of Doghouse :- Doghouse are created by following the design rules.

For this, sketch is created from the master section provided.
It is then made to closed body and is made to part model.
Shell operation is performed to get hollow structure and then coring is done in order to avoid sink marks in the class A surface.
Drafts are given for the surfaces as per design rules and proper fillets are also provided.
As per the given master section, ribs and supporting features are also added in the doghouse.
Then, the doghouse is added to the main body.

All the sketches used are iso-constraint.

ISO-CONSTRAINS SKETCHES :-