Week 8 - Challenge 3 - Coin Holder Design

% Creating the Coin Holder Plastic component through the given Class-A surface.

1] 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

• The created part must be changed to the material mode in the display frame.
• Compass is enabled and placed in the direction of the Tooling Axis.
• The lock command is then used to fix the compass along the tooling axis.
• Colour codes are classified and Draft angle is applied.
• Running point analysis is used to display permissible draft angle.

2] 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

Generally tooling axis is created using bisecting line method. But in the components where it has a bin, then the tooling axis is considered as a line normal to the base surface of the bin. The same is done with this component. A line normal to the base surface is created and considered as a tooling axis.

3] Screenshots of the Draft analysis report for both the given Class-A surface and the final plastic component

Procedure for performing Draft Analysis:

• Go to the Insert menu and select the Analysis option.
• Select Feature Draft Analysis.
• Select the Material option and select the surface.
• Drag the compass and place it on the tooling axis.
• Make sure that the top surface is in green color as the draft angle should not exceed 3deg.
• Click on Okay.

Class A

Image of the complete Draft analysis

Images of the colour scale variant

Final Plastic Component

Image of the complete Draft analysis

Images of the colour scale variant

4] Screenshots of the solid model with the proper colour code of the draft angle in various orientations (Isometric, Front, Side, and Top View)

a] Isometric view

b] Front view

c] Left view

d] Right view

e] Top view

f] Multi view

5] Screenshots of the tree structure with Geometrical sets having a proper name based on the sketches present inside of it.

6] Conclusion

We created the Coin Holder Plastic component through the given Class-A surface, the tooling axis for the given Class-A Surface and meeting the draft angle requirements and performed the draft analysis on the model at the end.

The thickness of the component is 2.5 mm