Door Arm Rest Week 8 Challenge

Plastic Product Design: Door Arm Rest (CATIA V5: Generative Shape Design)

Aim and Objective:

• Creating Tooling Axis following OEM Standards.
• Creating Class B Surface and Class C Surface using the given Class-A Surface as an input.
• Making Solid Part of 2.5mm thickness.
• Preforming Draft Analysis.

Class A Surface:

• As an input Class A Surface can be in Distorted form or in Separate parts and we need to correct it.
• Either we can Join those parts together or Extract them and then Trim them together.
• Note: We as plastic design engineers are not allowed to make any changes in Class A Surface.

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Tooling Axis Creation:

• Injection moulding includes Core, Cavity, and Sliders to make a plastic product.
• Core, Cavity, and Slider move/side in a particular direction which is called Tooling Axis.
• The tooling axis can be made using either by Bisection method or Plane as a reference.

Bisection Method:

• In a Bisection Method, we take intersection at XY and XZ plane.

• Using these intersections we make lines that are almost parallel to Z axis.

• These lines are then Bisected together to form a Final Tooling Axis.

Note: Reference to the above image, Final Tooling Axis is Pink in colour.

Slider Tooling Axis using Plane as a reference:

• Here a flat face is taken as reference and a point is created at the centre.
• A line is drawn from the point perpendicular to the face.

Class B Surface Creation:

• The surface at which features like Ribs, Screw boss, Dog house, etc. are made to support external mountings is called Class B Surface.
• Class B Surface is made by simply extracting A Surface, offset it to desired thickness and trimming them together.

• Fillets are added to the surface at the end to avoid any error.
• The Uniform thickness of the part should be maintained while adding fillets.

Class C Surface Creation:

• Class C surface is a connecting surface between Class A and Class B surface.
• Draft angle and Tooling direction are considered while making Class C Surface.
• Sweep with a reference surface is used to create Class C surface.

• Class A Surface is taken as a reference surface.
• White Surface indicates Class C Surface.

Solid Part With 2.5mm thickness:

• Class A, Class B and Class C Surface are trimmed/ Joined together to form a Final Trim

• The final trim is hollow from the inside.
• This final trim is filled with a solid using the Close Surface command. (Mechanical Design > Part Design)

Draft Analysis:

• The draft is an angle provided to the part with respect to the tooling axis to reduce friction between Part and Mould.
• Before moving towards draft analysis, it necessary to put 'materials' option active inside 'Customize View'

• Select Compass icon on Direction pane
• Move compass on the axis, make sure compass and axis are collinear.

• Part is provided with 3 Degrees of the draft.

• Area Highlighted has a minimum Draft of 1.87 Degree.

Slider Draft Analysis:

• Pocket Section is provided with a minimum of 3 Degrees of the draft.

Observations:

• Some area of the Door Arm Rest has Draft angle below 3 Degree (1.88 Degree), which need to be modified to reduce friction and easy operation of mould.

Conclusion:

• Tooling Axis for Door Arm Rest and Slider was created by following OEM Standards.
• Class B Surface and Class C Surface was created using the given Class-A Surface as an input.
• A door Arm Rest of 2.5mm thickness was created.
• Draft Analysis of Door Arm Rest and Slider was performed successfully.

Click/ Browse the Link Bellow for CATpart and PPT.

https://drive.google.com/drive/folders/1k2c-z8fX1S3na73WhmKJT1FC7MsaZnQ_?usp=sharing