Week 12- Final project

Aim :-

To create a CAD model of the "Door trim" by following the OEM standard from the given Class-A Surface and the Input Mastersection.

Software Used :-

CATIA V5

Input Surface :-

DOOR TRIM OF A CAR :-

Door panels works as an interface between the Interior of the car and workings of the door, and between vehicle user and the door. They are expected to meet a variety of design specifications regarding safety, aesthetics, and functionality. In addition, they are expected to continue the theme of the dashboard and pillars while concealing intricate electrical and mechanical components for operating locks, windows, and other features. The door panel has evolved from a simple two-part system of latch and simple winding mechanism to a more comfortable enclosure. Doors currently have an inner full-width panel consisting of electronic windows, central locking system, and speakers. These panels typically consist of a foamed core covered with either textiles or plastics.

HAVE A LOOK ON DOOR TRIM :-

CLASS A SURFACE:-

Class-A surfaces are those aesthetic/ free form surfaces, which are directly visible to us interior as well as exterior, It is having an optimal aesthetic shape and high surface quality. Mathematically class-A surfaces are those surfaces which are curvature continuous while providing the simplest mathematical representation needed for the desired shape/form and does not have any undesirable waviness. The aesthetics attracts the people can bring a desire in one’s mind to own that product .This is the reason why in design industries Class-A surfaces are given more importance. In automotive design, a class-A surface is any of a set of free-form surfaces of high efficiency and quality. Although, strictly, it is nothing more than saying the surfaces have curvature and tangency alignment – to ideal aesthetical reflection quality, many people interpret class A surfaces to have G2 (or even G3) curvature continuity to one another. Class A surfacing is done using computer-aided industrial design applications. Class-A surface modellers 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.

CLASS B SURFACE:-

Class-B surface are the surface counterside of the Class A surface.Every engineering aspects of joining,fastening, increasing the strength each and every engineering features are providing in the Class B Surface area.

CLASS C SURFACE:-
Class-C surfaces are the backside surfaces that can have tool marks, flash and other imperfections without hurting appearance, function, etc.

INJECTION MOULDING PROCESSES:-

When designing parts for injection molding,the manufacturing process is an important consideration. Injection molding is a process in which solid thermoplastic resin pellets are melted, injected into a mold, and then cooled back to a solid state in a new form. During both the injection and cooling stages of the manufacturing process, there are several factors that may affect the quality of the final product and the repeatability of the manufacturing process. Although it is not always possible to follow all recommendations, outlined on the following pages are some of the most fundamental guidelines when designing parts for injection molding.

B-SIDE FEATURES :-

BOSS:-

Bosses are used to facilitate the registration of mating parts, for attaching fasteners such as screws, or for accepting threaded inserts.Wall thicknesses for bosses should be less than 60 percent of the nominal wall to minimize sinking. However, if the boss is not in a visible area, then the wall thickness can be increased to allow for increased stresses imposed by self-tapping screws.

The base radius should be a minimum of 0.25 X thickness. Bosses can be strengthened by incorporating gussets at the base or by using connecting ribs attaching to nearby walls.

DOG HOUSE :-

Dog house is an engineering feature used in plastic trim design. Dog houses are used as supporting features. Sometimes other engineering features like snaps; locators etc. are mounted on them to increase their strength. Dog houses are subjected to draft analysis to prevent breakage of the component during ejection from mould cavity. Dog house and other engineering components are built on a B-surface.

Dog houses are used as supporting feature.Dog houses are subjected to draft analysis to prevent breakage of the component during ejection from mould cavity. Dog house and other engineering components are built on a B-surface.

4-WAY LOCATORS :-

These are the locators which arrest the 4 degrees of freedom by four ribs junctioning together. These are of the following type especially used for mold designs.

RIBS :-

Ribs are thin, wall-like features typically designed into the geometry of a part to add internal support to walls or other features like bosses. In a similar fashion, gussets are support features that reinforce areas such as walls or bosses to the floor. Ribs provide a means to economical stiffness and strength in molded parts without increasing overall wall thickness.

FUNCTION OF RIBS:-

• Locating & arresting components of an assembly.
• Providing alignment in mating parts.
• Acting as stops or guides for mechanisms.

A well-designed rib will overcome the following disadvantages:

• Increase part weight and cost proportional to the increase in thickness.
• Increase molding cycle time required to cool the larger mass of material.
• Increase the probability of sink marks.

USES OF RIBS :-

• Covers, cabinets and body components with long, wide surfaces that must have a good appearance with low weight.
• Rollers and guides for paper handling, where the surface must be cylindrical.
• Gear bodies, where the design calls for wide bearing surfaces on the center shaft and on the gear teeth.
• Frames and supports.

RIBS DESIGN INVLOVES 5 MAIN ISSUES:-

1. Thickness.
2. Height.
3. Location.
4. Quantity.
5. Manufacturability.

RIB GEOMETRY :-

HEAT STAKING :-

Heat Staking is a pulsed-heat process to join two or more parts out of which one at least is 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 de-forming 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 applications such as automotive, IT and consumer appliances.

HEAT STAKING BENEFITS :-

• Similar and dissimilar materials may be joined: metal to metal, plastic to plastic, metal to plastic
• Accurate control operating within a small process window
• Local heating resulting in no damage to surrounding materials
• Processing of glass-filled materials
• No mechanical vibration
• Many heat-stake shapes are possible through custom designed tools.

BEST SUITED PLASTIC COMPONENTS FOR HEAT STAKING :-

Heat staking technology is ideal for most native and blended thermoplastics on the market today, as well as the most robust glass and/or other-filled plastics. It produces high quality results when used with any of the following materials:

• Polycarbonate (PC)
• Polypropylene (PP)
• Polystyrene (PS)
• Acrylonitrile butadiene styrene (ABS)
• Nylons (GFN or Nylon 6/6)
• Ultem (GFN or Nylon6/6)

HOW TO CREATE THE TOOLING AXIS?

FIRST WE SHOULD LOOK INTO THE MATERIAL IF THERE IS ANY GAP IS THERE (USING THE BOUNDARY COMMAND) AND THEN LOOK DOWN INTO THE THREE DIRECTIONS (X,Y,Z) FOR A BETTER OUTCOME FOR THE PRODUCT WHILE MANUFACTURING. WHILE LOOKING THE VIEW THE ENTIRE PORTION CAN EASILY BE VISIBLE WHEN CHOOSING A DIRECTION.

THEN DRAFT ANALYSIS.

THE DRAFT ANALYSIS IS THE CORE THING WHEN COMES TO THE MANUFACTURING PROCESS. IN MANUFACTURING 3 DEGREE DRAFT IS MAINTAINED FOR A PRODUCT TO COME EASILY WHILE MANUFACTURING.SO THE MATERIAL SHOULD BE ANALYZED WITH A DRAFT ANALYSIS FOR A BETTER RESULT

HOW TO DO DRAFT ANALYSIS?

FIRSTLY WE NEED TO CHANGE THE MATERIAL (CUSTOMIZED MATERIAL). THEN SELECT THE COMPASS OPTION THEN MOVE THE COMPASS TO ALIGN WITH THE TOOLING AXIS PROPERLY. THEN CHOOSE THE LOCK OPTION TO LOCK THE COMPASS THEN SELECT THE MATERIAL THEN THE DRAFT ANALYSIS IS CARRIED OUT WE NEED TO CHECK IT SHOULD BE CLEAR THE A SURFACE AND C SURFACE THE MUST BE SET 3 DEGREES IF THE DRAFT WOULD NOT CLEAR THEN WE ALTER THE VALUES UPTO 3 DEGREE FOR EG ( 2.8,2.9)

PROCESS AND STEPS INVOLVED IN CREATING THE DOOR TRIM PLASTIC COMPONENT :-

• Primary step is to complete check to the Input Class A surface.
• If there is improper surface or any gap in the component we should update a Class-A surface.
• Then create a Tooling axis for the component for manufacturablity.
• Confirms the Tooling axis by using draft analysis.
• Then Offset the A-surface based on the thickness of the component.It creates the B-surface.
• Then Class-C-surface is created from the Class-A-surface based on the consideration of 3degree draft angle.
• Then Join the Class-A and the Class-C surface.
• Then do the final trim for the Class A+C and the Class B surface to make the closed surface.
• Use the Close surface command for the Final trim.
• Then do the Draft analysis (2.8 - 2.9) for better clearance of the draft.

IN THIS TOTAL 4 COMPONENTS OF THE DOOR TRIM :-

• ARM REST.
• MAP POCKET.
• BOTTLE HOLDER.
• LOWER SUBSTRATE.

ARM REST:-

Arm rest is the important part of the Door trim,It helps the passenger to rest their hand in very comfort way and this arm rest having a switches for a mirror controls.

INPUT CLASS A SURFACE:-

Input Class A Surface with the Tooling Direction.

DRAFT ANALYSIS:-

PLASTIC COMPONENT WITH ENGINEERING FEATURES:-

FLANGES FOLLOWING MASTERSECTIONS:-

MAP POCKET:-

Map pockets can be created integrally within the door trim panel by forming a projection region outwardly towards the passenger compartment and then providing a separate panel attached to the rear outboard surface of the trim panel. This type of map pocket protrudes into the passenger compartment. Another type of map pocket such as a recessed map pocket can also be formed within the door assembly such that the storage compartment of the map pocket is generally located between the trim panel and the outer metal panel of the vehicle door. An aperture in the door trim panel defines the opening into the map pocket.

CLASS A-SURFACE WITH TOOLING DIRECTION :-

MAP POCKET WITH ENGINEERING FEATURES:-

DRAFT ANALYSIS :-

BOTTLE HOLDER :-

Input Class-A surface and tooling axis

BOTTLE HOLDER WITH ENGINEERING :-

DRAFT ANALYSIS WITH ENGINEERING FEATURES :-

LOWER SUBSTRATE:-

LOWER SUBSTRATE WITH TOOLING AXIS

DRAFT ANALYSIS OF THE CLASS A SURFACE:-

WITH ENGINEERING FEATURES:-

FINAL PRODUCT:-

RENDERED IMAGE OF THE DOOR TRIM :-