Week 11 - Project - A pillar Design with Master Section

AIM:

To create the A Pillar Design with the master section given as the intersection sketch with the Class A surface and create the tooling axis and perform the Draft analysis for the final solid part.

CLASS A SURFACE:

Class A is an aesthetic surface with the highest quality finish. Most Class A Surfaces for an Automotive Component are made using AUTODESK ALIAS. It is taken as a reference by the Automotive Plastic Designer to create CLASS B, CLASS C surfaces.

TOOLING AXIS AND SIDE CORE AXIS:

Tooling axis is the direction in which a core or cavity of mold opens. This Axis is very important to determine the orientation of the component in mold, core and cavity design as well as to run the draft analysis of the component.

CLASS B SURFACE:

The thickness of the component as 2.5mm. Now we need to create a B surface which will be similar to the A surface at an offset value of 2.5mm. there are some discontinuities happened while offsetting the CLASS A surface so I repaired it to form a closed boundary by using the multiple extract, extrapolate, trim and fill surface commands and tools.

C SURFACE:

C surface is created with help of A-Surface by using the Sweep(with reference surface) and Boundary command separately, finally joined together to get the final C surface.

Then join the class A surface to the class C surfaces after that I trim out the joined A and C surface to class B surface to get the final object.

DOG HOUSE

Dog house is an engineering feature used in plastic design. Dog houses are used as support feature. Sometimes other engineering features like snaps, locators, screw bosses are mounted on them to increase their strength.

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

• Dog houses are designed to avoid SINK MARK created on the CLASS-A surface by screw bosses and to solve the length issues when giving screw bosses which need to be assembled to other components.

• It is also useful when perpendicular screw bosses are required on the part to the tooling direction.
• Make a rectangle to enclose the screw boss in it but make sure it is open from one side.
• Sweep it with tooling axis as the pulling direction inwards.

• Close the top face by using multi section surface.
• Thicken it by 2.5 mm to the outward direction.

  DRAFT ANALYSIS: From draft analysis, we can verify draft angles, examine the angle changes within a face, as well as locate parting lines, injection and ejection surfaces in parts.

  It is an important feature in Catia which helps the user to analyse the draft on various surfaces. The draft analysis toolbar provides two modes for analysis of the draft, first is the quick analysis which basically has three colours (green, red, and blue) for analysing on the other hand other option is the full analysis mode which enables a few more details into the draft and is used in the complex components.

  Draft analysis in Catia:

  Step 1: Ensure that customize view parameter is enabled and material mode is opted in view mode customization.

  Step 2: Now go to insert > analysis > feature draft analysis.

  Step 3: Drag axis bar to the tooling direction of part.

  Step 4: Check for draft.

  Surface will be in green if the draft angle is more than 3 degrees, blue if draft angle is between 0 to 3 degree and red if draft angle is less than zero degree.Three degree is the nominal value for draft, whereas 0.5 degree can also be manufactured at ribs.