Week 8 - Challenge 2 - Base Bracket Design
OBJECTIVE
Create the Base Bracket Plastic component through the given Class-A surface. To begin with, the tooling axis for the given Class-A Surface should be created meeting the requirements of the draft angle and at the end perform the Draft analysis on the model.
Detailed Report:
Class A surface:
It is the outermost surface of the automobile which gives aesthetic look to the vehicle. It is physically touchable. It is obtained from clay modelling by reverse engineering. This surface is given input to plastic product designer to work.
Class B surface
This surface is created by taking offset from class A surface. It is the surface on which all engineering feature like screw bosses, dog house, ribs & mounting are created.
Class ‘C’ surface:
This is the surface that joins class A & class B together.
Tooling axis:
It is the direction in which the core & cavity opens & closes.
DRAFT ANALYSIS
First, we have to check the continuity of the given class-A surfaces using BOUNDARY COMMAND OR JOIN COMMAND
BOUNDARY COMMAND
The boundary of the given class A surface is highlighted in the green line.
Extracting the boundary given Class-A surface visually.
TOOLING AXIS DIRECTION
Analysis of the tooling direction visually which is suitable. From the image, two holes are viewed from the top position
From X & Y direction we cannot clear two holes from this direction
From Z-direction both two holes are cleared and suitable for the tooling axis .
DUMMY TOOLING AXIS
X-AXIS
Y-AXIS
Z-AXIS
BISECTING METHOD
The bisecting method is used to find a real tooling axis. In order to create a tooling axis, create yz plane & passing through the reference point. Take the intersection of YZ plane with class A surface. Now two curves are created.
Now we have to check the surfaces creating problems for the tooling axis. Because the surface which is 90 degree to the tooling axis will be cleared. so make two lines which bisect to each other.
DRAFT ANALYSIS
To perform draft analysis .Go to insert >analysis >Feature draft analysis
Click on the compass icon and align it with class A surface
It is seen in Green in colour has more than 3 degrees for feasible draft angle.Also, see the colour variant display box.
INVERTING DRAFT ANALYSIS
FULL DRAFT ANALYSIS
FRONT VIEW
TOP VIEW
SIDE VIEW
CREATING B SURFACE FROM CLASS A
we separate class A into
Rib 1
Rib 2
Base surface
Rib 1 & Rib 2
Extract the flat surface
Untrim the surface
Extrapolate it
offset for 2.5 mm
For both rib repeat the procedure
Base surface
Extract the flat surface
Untrim the surface
Extrapolate it
offset for 2.5 mm
After offsetting A surfaces ,trim the all the surfaces to get class B final surface.
This final edge fillet in the inside of the surface.And use the Formula
Fillet radius = Class A surface fillet value + part thickness.
Creating C surface from surface A and B
Extract the boundary of class A surface and hole
Sweeping the boundary of class A surfaces & edges of the hole with the use of draft direction as tooling axis.
joining the class A and C surfaces together
Trimming the class b surfaces and get the final trimmed base bracket closed surface
Solid model
The solid model is created from part workbench .This is our final output design
ISO
FRONT VIEW
TOP VIEW
SIDE VIEW
