Challenge

Week 8 - Challenge 1 - Base Bracket Design

SSaravanakumar M K14 Jul 2022

Creating the Base Bracket Plastic component using Catia:

Class A Surface:

The Class A surface is gives is shown in below image:

Procedure:

Step 1 : Connectivity of the Class A Surface

Check the connectivity of the Class A Surface that is to check that there is no gap between the components using the Join command or by visual inspection or also by using the Boundary Command.

Step 2 : Tooling Axis

Then the Tooling axis for the component is to be found. Tooling axis is the axis along which the core and cavity or mould opens and closes. For this we see the Class A surface in all axis that is x,y and z axis.
In y axis cannot be tooling axis because the holes in the surface is to be manufactured using side core.
In x axis is also not possible for tooling axis as only one hole in the commponent is along the axis and another hole is not along the axis so it is to be manufactured using side core or lifter.
So the z axis is the tooling axis as all the holes and surface of the Class A is along the axis.
The Tooling Axis is created using Bisecting Line Method.

Bisecting Line Method:

In Bisecting Line method is that the possiblities or clearance is checked along the direction using the intersection of surfaces along the axis on the plane of the Class A surface and the two lines is created on the intersections walls that is along the inclined walls of the intersections. Then the line is created by using bisecting line option in line command using the two lines and the point created and that line is Tooling axis.

For Creating tooling axis we create the point. The image of point is shown below

Then the dummy axis is created along the point.
Then the intersection is created using yz plane and point as reference. The below image shws the intersection

Now line is created using the inclined walls of the intersection surface.
Then by using Bisecting of Line method is used to create the Tooling axis. The image below shows the Tooling Axis.

Step 3 : Draft Analysis

Draft anlaysis is done based on the tooling axis. Draft analysis is used to check the Class A is maintained with minimum draft angle of 3 degree.
The Compass is used define the Draft direction.
The green colour shows that the minimum draft angle is provided otherwise blue color is shown to the surface. The image shows that draft analysis of the Class A surface with color scale variant.

Step 4 : Creating Class B Surface

First three right side rib surfaces are extracted individually using Extract command.
Then the length of those surfaces is increased by using the Extrapolate command.
Then the extrapolated surface is Trimed using Trim command and the required rib surface is obtained.
Then Offset the rib surfaces using Offset command with 2.5 mm as thickness which is given.
This offseted Surface is the Rightside Rib.
Similarly left side rib surface , slanted surface and base surface is created using same steps.
Then the Edge Fillet command is used for filleting the edges with radius (2.5+3) 5.5 mm as the thickness is 2.5mm.
Thus the Class B Surface is created and the image is given below

Step 5 : Creating Class C Surface

The Class C surface is the connection between Class A and Class B surface.
The Boundary command is used to get the boundaries of the Class A surface.
These Boundary is swept using Sweep command with along draft direction option and draft angle is mentioned as 3dgree.
Similarly both the holes surface are created.
Now these holes and the surface obtained is joined with Class A surface using the Join command and Class C surface is obtained. The image shown below is Class C surface.

Step 6 : Final trim to obtain Base Bracket Plastic component

The last step is triming the Class c surface with the Class B surface.
Then the obtained surface is converted into solid using Close Surface and thus the final Base Bracket Plastic Component is obtained. The image is shown below is Base Bracket Plastic component

Screenshots of the solid model:

Isometric:

Front View:

Side View:

Top View:

Draft Analysis of the Solid:

Draft analysis is used to check the solid component is maintained with minimum draft angle of 3 degree.
The Compass is used to define the Draft direction.
The green colour shows that the minimum draft angle is provided otherwise blue color is shown to the solid. The image shows that draft analysis of the solid with color scale variant.

Screenshots of the solid model with the proper color code of the draft angle in various orientations: