Week 8 - Challenge 4 - Bumper
BUMPER DESIGN
AIM: to make a model from the provided class-A surface.
INTRODUCTION:
CLASS-A SURFACE: a surface made by the designer which is given as an input to the plastic modeler to work on. It is aesthetic surface
and the visible surface.
CLASS-B SURFACE: a surface below a certain thickness from the class-A surface is class-B surface. This is the hide surface that contains engineering aspects of a model.
CLASS-C SURFACE: a surface that joins class-A and class-B surfaces is class-C surface.
METHODOLOGY:
In this model we have focused on the following things:
Tooling axis
Draft analysis
Class-B surface
Class-C surface
Making a solid model from surface.
Following tools were used to reach the final step:
Extract
Un-trim
Trim
Extrapolate
Offset
Edge fillet
Boundary
Sweep
Join
Close (part design)
FOR DRAFT ANALYSIS:
First we analysis the model and then choose dummy axis in x and y direction.
As we intersected to proceed we observed that the side walls are not given any draft. Hence we assume the axis normal to the base surface and parallel to side walls. This surely will create problems because a minimum draft has to be provided.
As class-A surface is made by other designer only he is authorized to make changes, so we look over this to complete the coin holder for practice.
Now we go to insert< analysis< draft analysis and follow usual procedure to do the analysis.
Align the compass and click on the surface and as expected the model is mostly in red color i.e. negative draft with respect to the axis.
To correct it to as best as we can we moved the compass a bit till we got most of the surfaces in green and lock that position.
After hitting ok, we change the direction of the line from z axis to compass direction. The axis will align itself accordingly.
NOTE: as the side wall does not have draft, this result was expected and few areas need correction. But still we are moving forward to
complete the model.
CREATION OF THE TOOLING AXIS:
TOOLING AXIS :
It is nothing but the direction in which the mold opens and closes the draft angle needed to be provided by considering this tooling axis.
We can create a tooling axis by using the bisecting method.
BISECTING METHOD:
This method is used for the generation of the tooling axis for that purpose first we need to decide the direction of molding and then we create one dummy tooling axis for the reference to the purpose.
In this method, we select the surfaces which can create problems and take intersections with respective planes in the x and y-direction. By using these intersection curves we draw two lines and then draw a bisecting line from these two lines in the x-direction and y-direction.
After completing this we need to draw a final line bisecting these two tooling axis in the X and Y directions to get our final output.
FOR CLASS-B SURFACES:
We have divided the entire model into base, side walls, inside side walls and outer flange and worked on them one by one Everywhere we follow same procedure i.e. extract, un-trim, extrapolate, trim and offset. First base, then side walls. To avoid confusion, we trimmed both together and made them one. Also the fillet was given.
PATCH-1
PATCH-2
PATCH-3
FINAL CLASS B SURFACE
CLASS-C SURFACE:
SWEEP
CLASS-A & CLASS-C SURFACE
FINAL CLASS-C SURFACE
CLOSED SURFACE
ISOMETRIC VIEW
FRONT VIEW
SIDE VIEW
TOP VIEW
