Week 12- Final project
DEVELOPMENT OF DOOR TRIM PANEL
OBJECTIVE: The objective for this project is to make half of the door trim panel in catia-V5 from the provided Class-A surface of the same.
ABSTRACT: This report contains a brief theory on design rules and the approach followed to achieve the final plastic product. Draft analysis report on all the class-A surfaces apart from the procedure to make the class-B and class-C surfaces is also mentioned.
APPROACH:
Our basic approach to making a plastic model from a class-A surface should be:
Run draft analysis
Make tooling axis
Make B surface
Make C surface
Trim it all together and make it solid.
CLASS-A SURFACE
In the automotive industry, various teams work on various components, a car for example is not entirely designed by a single designer. There are many teams among which the task of making various components is distributed. And this is followed for every department of the industry. In this project, we are given a class-A surface which is designed in other software like Autodesk Alias, by a class-A designer. This is an aesthetic surface and a lot of time, effort, and good experience are demanded for making this continuous and good flowing surface model. This is the major reason why, when we get this as input we are not allowed as a plastic designer to make any improvements in the class-A surface. Rather, it should be brought to the attention of the seniors which later is conveyed to the concerned team and taken care of.
TOOLING AXIS
The tooling axis is the axis along which the core and cavity open and close. It is very important to define the tooling axis in the first step while designing a component as it is the main component that helps us to run draft analysis on class-A at the initial stage to see if we can move ahead. Also for the later stages, the tooling axis is the direction along which the class-C surface and the draft to the components are given.
In this model, we have a tooling axis in the perpendicular direction to the entire door trim which is a y-direction in the model. Switch bezel will require a side core, so another tooling direction is made specifically for the switch bezel. Apart from these two tooling axes we also have a side core tooling axis for the dog house.
DRAFT ANALYSIS
Our first step before starting the model should always be to check if the surface has enough draft that it will not create any problems while ejecting from the mold. This seems like a big task as we have to foresee something that will come at a very later stage. But this is done by a small process called draft analysis. This analysis tells us whether our component will be safely ejected in the tooling axis we have provided. Some components require a side core where there are undercuts, holes, or projections on the side walls, so for this, we need a different tooling axis, and a different analysis is required to check those areas. Draft analysis shows color codes that are defined by the user for different values which also are defined by the user. These colors help us to analyze if the component is clearing the analysis and whether we are good to go ahead or not. In case the component fails the analysis for class-A then we have to submit the draft analysis report to the higher authority so that the surface of the component can be improved. Failing analysis simply means that the component does not have the required draft value it must have. In case our solid model which we develop, fails the analysis at some parts then we have to correct it ourselves.
We have to make sure that our entire model is green which means it is clearing the analysis. So we have to run the analysis for class-A, solid model, and other B-side features as every single component, regardless of its size should be ejected safely from the core.
DRAFT ANALYSIS REPORT ON CLASS-A SURFACE
As we can see from our analysis the map holder needs improvements. On the industrial level in such case, we cannot proceed with this class-A, but for the project, we are making this model anyway. We expect this component to fail the analysis later too.
DESIGNING PLASTIC COMPONENT
As the entire door panel is divided into various components, we will make this plastic component in the same way. The following steps have been carried out to make the plastic component for every component:
The first step for every component was the same. The given input was not a single unit but had numerous patches. These patches were joined together using the join command. Thus after performing this operation, we got our single class-A surface.
Once we get class A, we have to proceed to make class B surface. Creating class B by extracting every flat surface will be a complex process in such a component. So we directly offset it by 2.5mm.
For making the class-C surface we have used the sweep command ‘with draft direction’ by giving a 3deg draft angle and tooling axis as direction. But at many places, this did not work so we had to sweep ‘with reference surface’ at 90deg. Once that was done, the C surface was joined together using the join command.
To make a final surface model, we have to trim all three surfaces together. And later go to part design to close the surface.
TOOLING AXIS
The tooling axis is the axis along which the core and cavity open and close. It is very important to define the tooling axis in the first step while designing a component as it is the main component that helps us to run draft analysis on class-A at the initial stage to see if we can move ahead. Also for the later stages, the tooling axis is the direction along which the class-C surface and the draft to the components are given.
For the creation of the tooling axis, there are different methods one is the Bisecting Line method for which a suitable surface is chosen. A point is placed in the middle of that surface for the creation of an axis system. A Point sketch is added to the Axis system to intersect the surface and an intersection of the surface is made on the surface. lines that seem to create problems in the molding are noted and an impression of it is made on the sketch and a bisecting line of the same is made. Now repeating the same procedure on the other perpendicular plane could give you another bisecting line. Now a bisecting line of the two lines obtained is created which will be our tooling axis. Another method is by choosing a suitable direction on a surface by visual analysis and doing the draft analysis for verification, this is a trial-and-error method
DRAFT ANALYSIS
Our first step before starting the model should always be to check if the surface has enough draft that it will not create any problems while ejecting from the mold considering the tooling axis. Some components require a side core where there are undercuts, holes, or projections on the side walls, so for this, we need a different tooling axis, and a different analysis is required to check those areas. Draft analysis shows color codes that are defined by the user for different values which are also user-defined. These colors help us to analyze if the component is clearing. In case the component fails the analysis for class-A then we have to submit the draft analysis report to the higher authority so that the surface of the component can be improved. Failing analysis simply means that the component does not have the required draft value it must have. We have to make sure that our entire model is clearing the analysis. So we have to run the analysis for class-A, solid model, and other B-side features as every single component, regardless of its size should be ejected safely from the core.
DRAFT ANALYSIS OF ARMREST (CLASS A AND FINAL PRODUCT)
The class A surface is not clearing for the draft analysis done. The design will cost the manufacturer a larger amount to create this part.
DRAFT ANALYSIS OF LOWER SUBSTRATE (CLASS A AND FINAL PRODUCT)
Both the class A and the part is clearing the draft analysis
DRAFT ANALYSIS OF UPPER MAP POCKET (CLASS A AND FINAL PRODUCT)
Both class A and the Part is clearing the draft analysis
DRAFT ANALYSIS OF LOWER MAP HOLDER (CLASS A AND FINAL PRODUCT)
Both class A and the Part is clearing the draft analysis
CONCLUSION:
The door trim panel was successfully created with all the design rules taken into considerations for feature attachment and the main part was created using the master section provided with the input class A.