Challenge

Week 8 - Challenge 4 - Bumper

DDharmendra Kumar12 Oct 2022

FEA

Week 8 - Challenge 4 - Bumper

AIM:

To make a model from the provided class-A surface.

OBJECTIVE:

To create a tooling direction.
To perform draft analysis for given A-Surface and prepare the final close body.
To design the Bumper plastic component by creating the B-Surface and C-Surface using the given Class-A surface.
Take the Thickness of the component to be 3 mm.

INTRODUCTION :

The input of the product designer is in the form of the A-class surface. The job of the product designer is to create the B and C surfaces keeping all the aspects for the mold.

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 outer most surface.

Visible surface and aesthetic look.
Surface with textures.
Surfaces provided by customer(OEM).
Don't have any features like(rib, snap, bosses, etc) on class A surface.
Class A surface is made from scanned data with different software like alias etc.
Surfaces which are having CURVATURE CONTINUITY IS CALLED class-A.

CREATING 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.

While creating the tooling direction in given class A surface. Chose the one suitable Base and Side wall and draw the line direction of axis.

Intersected the plane on class A
connected two out points by line.
Excruded the line by taking the point on the surface

DRAFT ANALYSIS :

The draft analysis of the Class A surface has shown the draft angle should be more than 3 degrees and this can be clearly observed from the above images that the surfaces have an angle of more than 3 degrees.

First, we analyze the model and then choose a dummy axis in the x and y directions.
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 the side walls.
This surely will create problems because a minimum draft has to be provided.
As the class-A surface is made by another 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 the 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 as best as we can we moved the compass a bit till we got most of the surfaces in green and locked that position.
After hitting ok, we change the direction of the line from the z-axis to the compass direction.
The axis will align itself accordingly.

NOTE: as the side wall does not have a draft, this result was expected and a few areas need correction. But still, we are moving forward to
complete the model.

DRAFT ANALYSIS FOR CLASS A SURFACE

DRAFT ANALYSIS FOR CLASS C SURFACE

FRONT VIEW

SIDE VIEW

TOP VIEW

ISOMETRIC VIEW

CLASS-B SURFACE:

A surface below a certain thickness from the class-A surface is class-B surface .This is the surface that contains Engineering aspects of a model.

Invisible Surfaces.
Surface mostly don't have textures.
Surface needs to be created according to the class-A surface.
Having all features(Rib,boss,snap etc) in B-side surface only.
Surfaces which is having tangent continuity is called class-B.

CLASS-C SURFACE:

A surface that joins class-A and class-B surfaces is a class-C surface.

Check the connectivity of the Class A Surface Ensure that there is no gap between the component, using join command. We can visually check it or by clicking boundary command. It has a boundaries outer. Therefore first check completed.