Week 9 - Project 1 - Door Applique Design with Engineering Features

Aim: To Create a solid body of a given Door applique and to create locators and Heat stakes on it as per design standard.

Introduction:

• Heat Staking

Heat staking is a pulsed heat process to join two or more parts out of which one at least made of plastic. The process is to deform the plastic material using heat and force at a set process time. The bond is made by partially deforming the plastic part in order to fix the other.

Heat staking makes it easy to bond metal to plastic and is commonly used in high volume/low cost application such as automotive, it and consumer appliances.

In manufacturing of thermoplastic components, it is often necessary to join the thermoplastic to a part of a dissimilar material, whether it can be a metal, dissimilar material or the other material. Thermal staking is an assembly method that uses the controlled melting and reforming a plastic stud or boss to capture or lock another plastic or a metal component of an assembly in place. The plastic studs protrude through the holes in a component to be locked in a place. The Heated thermal tip contacts the top of the stud, which melts and fills the volume of the tip contacts the top of the stud, which melts and fills the volume of the tip cavity to produce the head, locking the component in a place. The progressive melting of the plastic under continuous pressure forms the head. When staking, the right combination of heat and pressure for the application is critical.

Advantages of Heat stakes:

• Similar and dissimilar material may be joined; metal to metal, plastic to plastic, metal to plastic.
• Local heating resulting in no damage to surrounding materials.
• No mechanical vibration

• 2- and 4-way locators

In any kind of assembly before fixing the part to the mating part we need to fix the position of the part with respect to the mating part. In these cases, we need to follow some engineering principles. In this project we are going to follow 3-2-1 principle. Any part which has to be fixed during welding or machining process has to be fixed is having 12 degrees of freedom.

• Translation movement along X axis
• Translation movement along Y axis
• Translation movement along Z axis
• Rotational movement along X axis
• Rotational movement along Y axis
• Rotational movement along Z axis

Procedure:

1. Class A Surface

In automotive design, a class A surface is any of a set of freeform surfaces of high efficiency and quality. Class A surface modelers are also called ‘digital sculptors’ in the industry. Industrial designers develop their design styling through the A surface, the physical surface the end user can feel, touch, see etc.

2. Tooling Axis

Tooling axis is nothing but the direction in which the core and cavity opens and closes. Design engineer work is to analyses the class A surface and find out the best possible tooling direction keeping in mind all the draft angle is with respect to the tooling axis so that the components can be easily ejected from the molds.

3. B Surface Creation

B surface represents internal and functional surfaces. This cluster exemplary includes derived surfaces created by offset operation from class A surfaces to define thickness of material. This surface contains all the engineering features which follows design rules like locators, dog houses, screw boss, fillets etc.

4. C Surface creation

Class C surface is swept along the boundary of class A at an angle perpendicular to the Class A surface with respect to the tooling axis direction with a draft angle of 3 degree. 

5. Final Joint

After finishing all three surfaces, join the class A and class C surface together using the join command. Now, the joined surfaces are trimmed with class B surface to form a closed surface and thickening is done.

6. Draft analysis

Draft analysis enables you to detect the part we drafted will be easily removed. This type of analysis performed on the base of color ranges identifying the zones on the analyzed element where the deviation from the draft direction at any points, corresponds to specified values.

1. Go to insert
2. Click on the compass icon and align it with the tooling axis and click on the surface, we will get our result.

     7. Creating 2- and 4-way locators and Heat Stakes:

4-way locators mean you prevent movement at 2 axes (+X, -X, +Y, -Y) on the plane.

2-way locators you prevent movement only at 1 axis on plane.

While creating the locators we need to follow design rules to create the ribs in order to avoid the sink marks on the components.

Heat Staking is a pulsed heat process to join two or more parts out of which one at least made of plastic. The process is to deform plastic material using heat and force at a set process time. The bond is made by partially de-forming the plastic part in order to fix the other.

 

Conclusion:

• Thus, the door applique is developed by using given class A surface.
• 2-way and 4-way locators has been designed in order to fix the position of applique with the mating door panel and also designed the heat stakes which used to fix the component with mating panel by melting.