Week 9 - Attachment Feature Creation - Challenge 2

Aim :- To design the Dog House for the Door Trim considering the design rules.

Objective :-

1. To create a proper tooling direction.
2. To perform a draft analysis of the plastic component.
3. To design the Door Trim plastic component by creating the B-Surface and C-Surface using the given Class-A surface.
4. To create the Dog House for the Door Trim.

Tooling Direction :-

• In Molding machine arrangement is given to open the mold along a direction which is known as Tooling Direction.
• In other words, The mold is built from two separate halves (Core and Cavity) and tooling direction basically defines the direction of mold pulls apart.
• Tooling direction is known as primary direction.

Following Class-A surface has been provided to design the Door Trim.

• First of all, point is created at the center of the surface
• Intersecting curves are created of Class-A surfaces.
• Line is created in the verticle direction from the center. This line act as a Tooling direction for this component.

Draft Analysis of Class-A Surface :-

B-Surface :-

Class B-Surface is extracted from the A-surface and it is offseted by 2.5mm in downward direction.

C-Surface :-

C-Surface connects the class A-Surface and B-Surface. It is created using Sweep command. Boundry of the class A-Surface is swept in 3 degree angle.

Trim Surface :-

C-Surface is trimmed along the B-Surface then it is joined to the A-Surface.

Final Solid Body :-

Design of the Dog House :-

• Dog house is the feature used to avoid the sink marks.
• It gives support to the screw bosses at a specific height from the primary surface of the component.

• "C" is where the doghouse contacts the backside of the surface.

• Doghouse wall thickness at the intersection of the part wall ( C ) should be 40% or less than the main wall stock ( T ).

• The height of ( B ) should be between 3.0 – 6.0 mm.

Draft Analysis :-

Draft angles are tapers on part faces that help them eject from the mold properly. They are calculated as a degree measurement from the vertical axis of a mold, and they help account for the fact that injection molded parts shrink as they cool.

Without a draft angle, parts are more likely to stick to the mold and warp or break when they’re removed. Draft angles help reduce friction between the finished part and the side of the mold.

Draft analysis is performed based on colour ranges identifying zones on the analyzed element where the deviation from the draft direction at any point, corresponds to specified values. Minimum draft angle is considered as 3 degree.

Conclusion :-

Thus the Dog House for the door trim has been designed considering the design rules