Week 9 - Project 1 - Door Trim Lower with Engineering Features

AIM:
Create the Door Trim Lower 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.

Create the Heat Stakes and the locators considering the design rules mentioned in the video for the door applique.

CLASS A SURFACE:

It is surface which is made by the designer. It is aesthetic surface and usable outside futures are on this surface.

CLASS B SURFACE:

It is bottom side surface of class A surface. It is made by class A surface. It is formed with thickness distance from class A surface.

CLASS C SURFACE:

It joins the both class A and class B surfaces. This surface is equal to the thickness of the component.

TOOLING AXIS:

• Class A surface or part is used to manually analysis which is best for tooling and create the axis perpendicular to the product. It is called tooling axis. Mould is open and closed by this axis.

It is used to fix the model permanently. Rest of locator fixed side is fixed by it. It also in class B surface.

Tooling surface

\

Class B Surface

Class C Surface

CLOSED BODY

Draft analysis

SOLID SURFACE

Ribs are thin wall protrusions that extend perpendicularly from a wall or plane. They are usually found in clusters offering support to a plane that would have otherwise been too thick, but can also be stand-alone support for a single wall. They are commonly used to provide additional support and strength to a part. Thickness and location are essential to rib design.

First, the base surface where the rib has to be created is extracted using the Extract command.

Next, the profile is extruded, to find the height,h=Wall thickness * 5

=2.5*5

= 12.5 mm

Therefore, the height is 12.5 mm

The extruded surface is thickened,

Thickness,w=0.4*t

=0.4 2.5

=1mm

Therefore, the thickness of the rib is 1 mm

The draft is applied to the sides of the ribs. As per the design rule, the ideal draft angle is 0.5 deg

Then fillet is applied to the faces of the rib. As per the design rule, the fillet can be 0.25 mm.

The locators restrict all the other degrees of freedom except the translation along the direction of tooling axis Le along y-axis. For restricting that degree of freedom we will be using the heat stakes.

In heat staking, we use local heating and cooling to raise the temperature of plastic components and allow plastic reforming to be carried out.

The draft is applied to the sides of the ribs. As per the design rule, the ideal draft angle is 0.5 deg

Then fillet is applied to the faces of the rib. As per the design rule, the fillet can be 0.25 mm.

These heat stakes will enter the mating component and using a heat staking machine these heat stakes are melted and cooled. When cooled this will get hardened and the two components will stick together. Thus all degrees of freedom are arrested

Then, the ribs are created by following the rib design rules.

The draft is applied to the sides of the ribs. As per the design rule, the ideal draft angle is 0.5 deg

Hence, the ribs are created for the screw HEAT STAKES

Now we will see how the plastic part is fixed onto the other plastic part. The door applique is fixed on to the door surface with the help of locators and heat stakes. Every component in space has 12 degrees of freedom. So these locators and heat stakes restrict all these degrees of freedom.

Locators are 4-way locators. The locators will follow the rib design guidelines and will be given a minimum draft of 0.5 degrees and a minimum fillet of 0.2mm and an entry chamfer of 3mm. This entry chamfer is given so that the locators can mate with the other part easily.

CREATING THE DOGHOUSE

The dog house is an engineering feature used in the plastic trim design. Dog houses are used as a supporting feature. Sometimes other engineering features like snaps; locators, etc. are mounded on them to increase their strength.

The doghouse is created by following the design rules.

The nominal wall thickness guide range is from 0.75 mm to 3 mm for reinforced materials and 0.5 mm to 5 mm for unreinforced materials.

Related Courses

WALL THICKNESS (W) = 0.70 (NOMINAL THICKNESS OF PLASTIC MATERIAL)

This process is usually done by Thicken surface command.