Week 11 - Final project

Final Project Report

Objective

The Objective of the Project is to create/develop the entire structure of a Door trim panel with Given CLASS A part file.

Product File Creation

This is the very first step of this project.The main aim is to bring in the part file into an assembly environment and work on developing it in said environment.Hence using "Exisisting Part Import" command in the assembly workbench we bring in the CAT part file of door trim panel. Later we make three copies of same file and in eacch copy we save any one component of the panel. Now we have Arm rest,map pocket,dome and lower substrate in seperate part environments but in the same assembly environment.

CLASS A, B, C Surface creation

In each of the different parts we have the class A as the input.The first step is to analyse the surface of the class A and check for incorrections,abnormal surfaces,Missinf surfaces etc.Then we rectify these to create the "Improved class A ".

Next, we move on to creating the class B. To do this in complicates structures as in this project we ooffset the entire class A to the Class b side.(Here,thickness = 2.5mm
).While doing so we will,in most cases get erronous regions,missing surfaces etc.We need to rectify these errors.Later we extapolate the class b with an angle of "0 degrees" for about 3-4mm.Extrapolation can be done by either "Extrapolate"or "Sweep" command.Then we trim these swept surfaces together to get the "Extrapolated Class B".

Finally we move on to the class C surface creation. Here we create a surface from the edge of the class A at 90 degrees (with draft) in such a way that the surface created isn perpendicular to class A and piercing through class B to create a closed surface structure.We Join the class C with class A and trim it with the extrapolated class B surface.

Finally we use "Close Surface" command in the part workbench to create a solid.

B side features using Master section

In this project all the parts are seperate from each other.To construct them together to form a door panel we need to attach them with each other. We use the mastersections given to identify the structure needed, the place it is needed and the dimensions and thickness of the features.In our case we have created Flanges in arm rest, dome and map pocket to connect them with lower subtrates via heatstakes.

The number of stakes is proportionate to the number flanges.The stake passes right through the flange to later melt in itself and form an attachment.The number of flanges needed and places where it is needed is upto our us.

Also I have created two doghouses and and two 4 way locators on the lower substrate as B side features.Finally all the B side features need to be added tto their respective part structures to form the final body.Afterwards we assemble the pushpin on the doghouses using assembly constraints after fix the Lower substrate.

Tooling axis creation and its purpose

A tooling axis is an axis which passes through the body of the part created in the mould.It defines the direction in which the cavity and core move to clamp and clear the part to be created.It can be either the x , y or z axis directions.It is decide by the designer for easy clearance and cost effecctive ness in creation of the mold

In CATIA, we decide th tooling axis to be perpendicular to the flat surface ansd holes of a part as much as possible.Initially we create a dummy tooling axis.Later we check the different surfaces,fillets etc which are perpendicular to the tooling axis . To check any doubtful surface(if whether they can be ccleatred or not) we use the bisecting Method.In this method we select both the planes parallel to the tooling axis and create an intersect with the classA surface an the plane.Now we extend the lines of the surface which may be a hindrance.Later under Lines--->Bisection line--->select both lines---->select the line falling on dummy tooling axis(or next to it).This line becomes the original tooling axis

This above method is the Bisecting Line method for creation of the tooling axis.

Another way to create a tooling axis on complex Class A surfaces is by view the class A at different views and seeing from which view most number of planes are seen.Then select such a view and select a large plane on that view and draw a line normal to that surface passing through the class A.Now a majority of the surfaces on the part can be cleared by tooling axis alone.

Draft analysis

All surfaces of the solid parallel to the tolling axis can be cleared easily along tooling axis. Other unclear surfaces which are at an angle with the tooling axis need to be cleared by giving a draft. Here during creation of class C surface the sweep command is give along a curve with respect to the draft direction along the tooling axis. A minimal draft of 0.5 to 3 degrees is only required for proper clearance of solid.