Week 11 - Final project
Aim : To create a CAD model of a side door trim panel from given class A surface .
Objective:
a) Creation of side door trim panle from given class A surface . Apply thickness to it and use attachment features .
b) Creation of flanges and heat stakes from given master sections .
c) Creation of dog house and various attachment features using industry standards
d) Performing draft analysis and ensuring the features and surfaces clear it .
Introduction :
The ten stages in automotive product life cycle developement are listed below .
1)Concept sketch
2) Styling class A
3)Feasilbility check
4)Concept validation
5)New product design
6)Product developement
7) Prototyping
8)Design validation
9)Pilot production
10)Mass production
From the above stages , it isin stage 5 that new product is developed and validated from class A surface . The objective is to design class B and class C surface from given class A surface and create a solid body from it using softwares like CATIA V5, solidworks or solidedge taking into consideration the draft analysis which makes the component suitable for production using injection molding process .
Given below is the procedure to create a new plastic component from given class A surface .
1) Creation of tooling axis
2) Creation of class b surface
3) Creation of class C surface
4) Creation of closed body
5) Draft Analysis .
Draft analysis is done to ensure that the designed part is manufacturable based on the draft conditions applied. It is done to ensure the proper ejection of the component from dies(for metals) or molds(for plastics). The basic idea is to ensure that the tooling axis has to be created in such a wat that it has no parallel surface profiles of the component so that the ejection of the components can be ensured . Tooling axis is the axis along which cavity and core are closed and opened .
The main components of interior door panel of a car consists of the following parts .
1) Arm rest
2) Map pocket (Consists of upper and lower part)
3) Upper substrate (Not given in the current model)
4) Lower substrate .
Step by step procedure
1) Creation of tooling axis
To create tooling axis , we must import the model into catia as a product .
File=>open=>browse=> MASTER SECTION DEVELOPEMENT.igs file .
Given class A surface
Rear side of the class A with master section
Create a product file and copy each component into different part files and name the accordingly .
Creation of Tooling axis for Arm Rest
1) We have split the arm rest into 2 parts for simplicity of creation.
The parts were named as arm rest part 1 and arm rest part 2 respectively
Procedure for tooling axis creation
Step 1: Insert a geometrical set . Extract the base surface and create a point at its center using point on surface option from point tool. Look for suitable axis to create a tooling axis so that all faces clear tooling .
Step 2: Create an axis system without current option ticked at the above point. Create a position sketch with zy plane from axis system and above point as reference point.
Step 3: Use intersect 3d objects option from project tool to create 2 lines by selecting a suitable plane(zy). Now create 2 lines which coincide with lines on both sides of the projection point . Create a line using bisect option .Allign the line in required axis direction.This is our Y tooling axis .
Step 4: To create tooling axis about x direction, create a position sketch with xz plane as reference plane and projection point as the first point we created . Use cut section tool and create an intersection using projection tool . Now create a line that coincides with this line .
Step 5 : Draw a line from origin in horizontal direction and create and angle constraint of 5 degrees. Use bisect option to create a line between that above lines . This is out X tooling axis .
Step 6 : Create a new line using bisect option between X tooling and Y tooling line . this is our required Tooling Axis , Name this as tooling axis and publish it .
Procedure to check for Draft analysis
1)Once the tooling axis is created , publish it and the component using Publication from tool option .
2)Insert Feature draft analysis option from insert tool bar
3) Change the view option to customize view parameters and click on material option under shading .
4) Now click on the axis option from Draft analysis tools , allign it with tooling axis and click on lock option to lock it .
5) Change draft angle value to 3 degree . Click on quick analysis mode to display feature according to given color scale . Check from all views to ensure the draft analysis is cleared .
6) Since the created tooling axis does not clear the draft analysis at the created axis , click on the lock axis button to unlock it . Now rotate the tooling axis by left clicking on the top round portion of the axis system . Rotate the axis till maximum clearance is obtained . Now right click on the axis and click lock current axis .
7) Create a line using the initial axis origin and this axis using point and direction (using compass direction) option . This is our required tooling axis .
8) Now if we check for draft analysis, we can observe that the ribbed area has not yet cleared draft analyisis. Hence we need to create a side core tooling axis . To do this , create a line using point and direction option with Y direction .
9) Repeat steps 1 to 5 to ensure the remaing portion which was not cleared using Tooling axis has been cleared using this axis .
Similarly created tooling axis using same procedures for all other components .
Tooling axis for Arm rest part 2 
Tooling axis for lower substrate
Tooling axis for Map pocket upper
Tooling axis for map pocket lower
Here we can observe that regions in blue colour has a 0 degree draft angle . This would lead to ejection problems while molding process . Hence the class A surface has to be modified to meet draft requirements Hence we have created tooling axis for all components .
2) Creation of class B surface
Procedure to create class B surface for Lower substrate .
Step 1: Use offset tool with a distance value of 2.5mm to create offset of class A surface .
Step 2: After offsetting , extrapolate tool was used to extend all the edges of this surface . This is done to ensure that the parting line comes at B surface .
Step 3: In areas where extrapolate was not possible (Fillet or cusped surfaces) multisection surface option was used .
Step 4: Join all the extrapolated surface and multi section surfaces to obtain a single surface .
Hence the class B surface was created for lower substrate .
Similarly , class B surface was created for other components .
Class B surface of arm rest PART 1
Class B surface of arm rest PART2
Class B surface of map pocket upper
Class B surface of map pocket lower
Hence class B surface for all components were created .
3) Creation of Class C surface
Procedure for creation of class C surface for Upper map pocket
Step 1: Use sweep command to create a new surface an an angle with respect to a surface . This angle is dependant on draft angle for free edges and ususally 90 degree for mating surfaces .
Step 2: In areas where sweep is not possible , use Multi section surface to create a new surface .
Step 3: Join all surfaces to obtain C surface.
Hence C surface was obtained for upper map pocket
Similarly C surfaces were obtained for all other components .
C surface for Lower map pocket .
Class C surface for Arm rest part 1
Class C surface for Arm rest part 2
Class C surface for Lower substrate
Hence class C was created for all components .
4) Creation of closed body
Procedure for creation of closed body for lower map pocket .
Step 1: Use trim or join option to join Class A and Class C .
Step 2: Use trim option to join above trim with class B
Hence we have obtained closed body .
Similarly closed body was obtained for all other parts
Closed body for upper map pocket
Closed body for Lower substrate
Closed body for Arm rest part 1
Closed body for Arm rest part 2
Hence we have created closed body for all parts and thus we have created solid bodies from them .
5) Draft Analysis
Procedure to check Draft analysis for Lower substrate .
1)Once the tooling axis is created , publish it and the component using Publication from tool option .
2)Insert Feature draft analysis option from insert tool bar
3) Change the view option to customize view parameters and click om material option under shading .
4) Now click on the axis option from Draft analysis tools , allign it with tooling axis and click on lock option to lock it .
5) Change draft angle value to 3 degree . Click on quick analysis mode to display feature according to given color scale . Check from all views to ensure the draft analysis is cleared . Click ok to complete the Draft analysis mode.
Draft analysis for Map upper pocket
Draft Analysis for Arm rest part 1
Draft Analysis for Arm rest part 2
Hence we have completed first part of the project and have obtained closed body for all the parts clearing draft analysis
