Week 8 - Challenge 4 - Bumper

BUMPER DESIGN CHALLENGE 4

AIM : Create the Bumper Plastic component through the given Class-A surface.

THEORY :

TOOLING AXIS :

Tooling axis is the direction in which the core and cavity opens and closes. In order to construct the Class B and Class C surfaces, it is crucial to determine the tooling axis from a Class A surface since this axis serves as a reference line for the draft angle.

In this challenge, the tooling axis is discovered by just sketching a line perpendicular to the surface as shown below.

BISECTING METHOD :

• It's a method of finding tooling axis. In order to find the tooling axis we need to under find the better tooling direction by analysing the body.
• Finding tooling axis should be in a manner which will reduce the manufacturing cost, like wise there will be some better tooling direction which can avoid the use of side core.
• If we get the better tooling direction as Z axis. Firstly find the tooling direction in X and Y axis if there are inclined surface to be considered this is achieved by intersection solid and bisecting method.
• After finding both the tooling axis in X and Y direction, bisect it to find the main tooling axis.

DRAFT ANALYSIS :

In order to recognise that our drafted component is at an angle that is higher than the typical draft angle, which is about 3 degrees, draft analysis is employed. Draft analysis is done using a tool in Catia called "Feature draft analysis." When you click on this tool, the window below will appear.

• In the mode section, there are two modes: the Quick analysis mode and the Full analysis mode. In this challenge, quick analysis mode is being used to visualise draft analysis.
• First, a tool named "Compass" from the direction category is used to define new draft direction. The direction of the draft is determined by positioning that compass above the tooling axis.
• Then by just clicking over the surface or the component we can visualize the colour corresponding to the angle as set in the draft analysis.
• There is an another tool which is used to find angles at running points. The tool is under display category, in that by selecting the tool named "Analyses under the running point" there by moving the cursor over the component gives the draft angle at that particular point on the component.
• There is an another tool to change the draft direction of the compass, which is under direction category next to the compass tool.

PROCEDURE :

• Tooling axis is found as explained in the theory section.
• By Feature draft analysis tool the draft analysis of the class A surface is done initially to know whether our find class A is acceptable or not. And the given class A is acceptable.

DRAFT ANALYSIS OF CLASS A

• Then nextly creating class B surface just by offseting class A by 3.0 mm.
• The class B will have some gaps on the surface and those gaps are cleared by multi sections surface command.
• After solving those gaps in class B, class C surface is created, then trimmed the unneessary portions to get the exact bumper design.
• By using close surface command in the part design the surface body is converted to part body.
• Then the draft analysis of that particular part body is performed.

DRAFT ANALYSIS OF PART BODY

ISOMETRIC VIEW

FRONT VIEW

LEFT END VIEW

RIGHT END VIEW

TOP VIEW