Week 8 - Challenge 1 - Base Bracket Design

  Aim 

     To Create the Solid part body of BASE BRACKET from Class - A surface

  Objective 

     The Objective of this challenge is to create Base Bracket Design along with Solid Part Body from class A surface following OEM design standards in Catia Surface Workbench and Part Design.

   Input Class - A Surface

      

   Solid Part Body

      

      

     

    

    

   

   

   

   Description

      Four stages of design life cycle are as follows:

        Concept sketch : These are the imginative and innovative sketches . Concept  sketches can be designed as collection of visual cues sufficient to suggest the design to an informed observer. These are the basic sketches which provides general idea about design of the product . These sketches are provided to system either in 2D or isometric form .Example,concept sketch of an automobile

        Class A Creation : Class A surface refers to those surfaces which are VISIBLE and abide to the physical meaning,in a product foe styling - class A surfces of automobile ALIAS siftware is used . These class-A surfaces are used as an input for an input for an Automotive Plastic Designers

        Clay Modeling: In clay modelling class A surfaces are provided to clay modeler who design actual model of automobile using industrial clay. Class A surfaces and clay models are co-related,using clay modeling physical representation of design is possible which helps in further modifications in the design of the vehicle.Clay Modeling of an automobile is most common example of clay modeling .

        NPD CAD : New Product Develpoment (NPD) Cpmputer Aide Drafting (CAD). This process involves forming strategy, organizing requirements, generating cocepts, creating product.

    Tooling Axis creation

        Class - A surface is first analyzed to create tooling axis or tooling direction that molds pull apart in injection molding. tooling direaction is vital for plastic product design as it decides direction for mold seperation.

   Steps followed for creation of tooling axis

         1. Reference point first created on extracted surface

         2. New axis system is deployed to plot clearence line.

         3. The x direction and y direction along the class a were used to create tooling axis

         4. Two clearing lines were bisected to form Tooling axis

         5. Graphic properties of tooling axis were change before publishing.

    Draft analysis

       Draft Angle: The draft angle is the amount of taper for molded or cast parts perpendicular to the parting line. It can be measured in degrees or mm/mm(in/in). As plastic cools, it shrinks and therefore shriks onto molding surfaces because of this and a few other reasons, we draft ( angle) the walls of the plastic part, so as the part is removedit breaks free from the molding surfaces easier and without draging. A fuctional part of injection molding has to have drafts facing both cavity and core sides to reduce the risk of damage to the parts and ensure ejection. whats also important is to overcome the vaccum forces by letting air in between the metal and the plastic for the part to release properly. Adding an adequate draft angle ensures that warpage upon ejection is prevented while maintaing a decent cosmetic finish.

      Draft angles are generally a requirement of injection molding design( though there are a select few soft materials,like nylon, that can get away with draft angle of zero).

      Draft should be a part of design for manufature, and Plastic Product Designer should be aware of its need at the outset of the design process. This allows consideration for design requirements to be taken into account.

    Nominal Values For Draft angle

       1. 3 Degree is nominal Draft.

       2. 5 Degree can also be manufactured. But it will increase the manufacturing cost.

       3. 7 Degrees for textured surface.

   Importance of DRAFT in injection Molding 

       1. Reduces the chance of damage to the part due to friction during release

       2. Reduces wear and tear and chances of damage to the mold

       3. Ensures a uniform, smooth ,unscratched finishes and textures

       4. Reduces overall cooling time by lessening or eliminating the nees for unconventional ejection setups

       5.Most ,if not all, of these benefits offer either direct or indirect over all production cost reductions.

    Steps followed for Draft Analysis

        1. The part created has to be changed to material mode in display frame.

        2. Compass is enabled. Align compass along with tooling direction .

        3. Lock command is then applied to fix compass along with tooling axis.

        4. Color codes are classified and Draft angle is applied.

        5. Running point analysis is used to display permissible draft angle.

    Draft Analysis report