Challenge

Week 9 - Project - A pillar Design with Master Section

VVidhan Shah23 Dec 2022

Project - A pillar Design with Master Section

AIM

To make a fully solid model from the provided master section and class A surface.

INTRODUCTION:

MASTER SECTION:

They check and give new alteration models in 2D with class A surface which is used to make a 3D model for the next step of designing.

CLASS A SURFACE:

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

CLASS B SURFACE:

It is the bottom side surface of the 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 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 analyze which is best for tooling and creating the axis perpendicular to the product. It is called the tooling axis. Mould is opened and closed by this axis.

DOG HOUSE:

It is used mainly for three functions.

To eliminate the sink marks
To lift the bosses to hight
To give outside bosses from B surface

RIBS:

Ribs give strength to the model. It is made by some guidelines like draft, fillets, etc.

1] Master Section

Master sections are the guides for design requirements that decide the component packaging after technical (Styling, Concept, or Class-A) surfaces. Creating this master section should need 5 to 6 years of experience.
This helps you to decide the feasibility, clearance, packaging, and fixation strategy before working it on a 3D. We have a master section.

2]CLASS A SURFACE

check the surface quality

3] TOOLING AXIS

In injection molding, the Class A surface is first analyzed to determine the axis or tooling direction that separates the molds. Tooling direction is critical for plastic product design because it determines mold direction.

TOOLING AXIS CREATION

The tooling axis here created is by selecting one of the natural axes as it clears the draft.
Here, the tooling axis is created by extracting one of the surfaces for creating a point and a new axis is created at that point.
So, a flat face is extracted and created a point at its center. Axis is also created at that point.
Now, the line is created using the line tool and giving line type as point-direction and selecting the point and direction for creating the tooling axis and the tooling axis is created along x direction.

4] Creation of Class B and Class C Surface

Class B

To create the class B surface, offset the class A surface inside as per our thickness requirement (here the thickness is 3mm, so I offset the class A to 3mm inside).
Once the offset is created, we can observe some patches on the offset surface by taking the boundary for the offset surface, those patches are formed due to the fillets on the class A surface.
We covered the patches by using the different surface commands (multi sections surface, fill, blend) in the Generative Shape Design workbench.

Class C

To create the class C surface concerning the boundary of the class A surface, I used the sweep command. Initially, I extracted the boundary of the class A surface with tangent continuity, and I sweep the extracted boundary concerning the surface at 90deg (for draft angle) for 4mm to intersect properly with the class B surface.
Once we sweep all the surface boundaries of class A, extrapolate the swept surfaces until both surfaces got intersected properly, and trim them to remove extended extrapolated surfaces to get a proper sweep boundary throughout the entire surface, including the center hole of the bumper.
Now, join both class A and sweep the boundary to get the complete class C surface.
Now Class A surface and Class C surface are joined.
Now Class B surface is also trimmed with the obtained surface to get the closed surface.
A boundary check is done to check for any open boundaries in the part. The closed surface is then obtained and moved to part design and the close surface tool is used to obtain the part.

5] Closed Surface

6] DOG HOUSE & RIBS

Create the dog house & ribs as per the master section.

For Rib Design:-

Undercut in Dog House:-

Hole At Top Of Dog House:-

DRAFT ANALYSIS:-

For molded or cast parts, the draft angle is the amount of taper perpendicular to the parting line. It is measurable in degrees. Because plastic shrinks and sticks on molding surfaces as it cools, we draft the walls of the plastic part so that it ejects or breaks free from the molding surfaces more easily and without dragging. To reduce the risk of damage to the parts and ensure ejection, a functional injection molding part must have drafts on both the cavity and core sides.

Nominal values for Draft angles

3 Degrees is a nominal draft angle.
5 Degrees can also be manufactured. Increasing the manufacturing cost.
7 Degrees is considered for Textured surface parts.

Importance of Draft in injection molding

Reduces the possibility of part damage due to friction during the release.
Reduces mold wear and tear.
Ensures a uniform, smooth, unscratched finish.
Ensures the integrity and uniformity of other surface finishes and textures.
Reduces overall cooling time by reducing or eliminating the need for unusual ejection setups.

Steps followed for Draft Analysis