Week 9 - Challenge 1 - Base Bracket Design

BASE BRACKET DESIGN CHALLENGE

In this exercise, a base bracket is designed using the given class A surface.

Class A surface 

The class A surface is then checked for any irregularities or gaps by using boundary tool or other methods.

 Finding the Tooling Axis

Tooling axis is defined as the direction at which the movement of cavity or the core takesplace during the manufacturing process.

After ensuring there are no gaps in the class A surface, it was determined that the tooling direction would be along the Z axis initially due to the presence of the hole. But in order to find it we have to use bisecting method.

Finding tooling axis using bisecting method 

• A dummy tooling axis is created initially at the centre of the hole on the flat surface.
•  The class A surface is divided to different parts and different colors are given for easy identification.
• Intersect the class a  surface along the  YZ plane where the surface is more.
• The ribs of the Class A is the only area that has a chance to be parallel to the dummy axis and to not clear the analysis, so extend the two lines on both sides .
• A  bisecting line is created from the two extended lines.
• It is found that the new line is  perfectly aligned with the dummy line. Therefore, it is taken as the tooling axis.
• A different color is given for the main tooling axis

Draft Analysis

A draft anaysis is conducted to determine whether the part is manufacturable or not. Here the minimum draft angle is 3degrees is advisible.

Draft Analysis of Class A surface.

Steps in draft analysis

• Before doing the draft analysis, 'material' option should be activated from the material view icon.
• Then select the command for draft analysis and select the button with axis.
• Bing the axis bar and align with the tooling direction.
• Check whether the part clears the draft analysis.
• The surface which clears draft analysis with minimum 3 degree is shown green and below that blue and red  is given.

Creation of  the Class B surface

Class B surface is the surface which have the engineering features like connectors and ribs and class A surface is the asthetic sufrace.

For creating Class B surface, the two ribs, the slanting face and the flat face are extracted from Class A surface and is  offseted by 2.5mm, which is the given thickness of the part.

Steps for creating Class B surface 

• The Faces fron the ribs and the flat surfaces are extracted from class A surface .
• Then they are offseted to 2.5mm and untrimmed .
• Then the surfaces are extrapolated and trimmed to for the surface without fillets and named rib 1 and rib 2.
• The flat surfaces are made using the same steps .
• The surface is extrapolated and trimmed to get the final B surface 
• During filleting the we have to add the thickness value with the fillet value.

Class B surface made from class A surface.

Class C Surface creation

Class C is the surface which connects Class A and Class B surfaces according to the draft angle and tooling direction.

We have to make sure that B surface is extended at least 5mm from A suface.

Steps 

• The boundary of the A surface is taken and tooling axis is unhided
• Sweep commad is used and draft degree is given as 3 and the direction in the downward is choosen.
• The holes on the surface are also made using sweep command.
• These sweep surfaces are joined to form the C surface.                                                                          

sweep done on the holes and boundary of the surface to form class C surface.

Class C surface is created using the Sweep command and the boundary of the class A and holes are taken as guide curves. The draft angle is given as 3 degrees.

The Class C suface is formed by joining the sweeps of the surface with Class A surface.

class C and class A surface  joined.

Then the final surface is obtained by trimming the suface with class B surface.

Final trim to get the base bracket .

The closed surface is created using close surface command in the part workbench.

closed body surface

Draft analysis of the final trim base bracket 

THe draft analysis of the final surface is done following the same procedures and is cleared.

Draft analysis of base bracket.