Week 12- Final project
AIM
To create Door Trim Panel Assembly by creating individual components through a given Class A Surfaces - Arm Rest, Upper Map Pocket, Lower Map Pocket, Lower Substrate and Using given Master section to create B Side features – Locators, Heat stakes, Dog Houses in individual components considering design rules and perform Draft Analysis on the final plastic component and assemble the given Push pin clip on respective area.
OBJECTIVE
- To make sure that the model meets the requirements of the draft angle.
- To create the Tooling axis using bisecting method / suitable axis.
- To perform Draft analysis on the given Class A Surface.
- To create the required Class B and Class C surfaces.
- To obtain a solid body from the surface using Close Surface feature.
- To create the B side features through given master section, considering design rules.
- To perform draft analysis on final plastic component.
- Above procedure followed in creating individual component.
MASTER SECTION
- Master section development takes place during the feasibility check and concept validation stages of the product life cycle.
- These are typically the guides for design requirements and which decide the component packaging after the development of the concept design, i.e., class A surfaces.
- The master section helps us to decide the feasibility of the concept design, the clearances, the packaging, and the fixation strategy of a component before converting the concept design into a solid 3D engineering design.
- During the period of vehicle concept design, the evaluation of the master section performance depends mainly on the reference vehicle data and the experience of the structural design.
CLASS A SURFACE
- Class ‘A’ surfaces are primarily used in the automotive environment and refer to those surfaces which are visible in a product. In other words: A - class surfaces are those aesthetic/free-form surfaces, which are visible to us (interior/exterior), and have an optimal aesthetic shape and high surface quality.
- The surfaces or regions which are visible nowadays are considered for Class-A modelling. It is one of the reasons why the importance of Class-A modelling is increasing day by day. Majority of the time this term is used in Plastic Part designs.
Arm Rest
Upper Map Pocket
Lower Map Pocket
Lower Substrate
CLASS B SURFACE
- The Class B surface is created from the Class A surface, keeping the thickness of the component in check.
- The Class B surface resembles an offsetted surface from the Class A.
Arm Rest
Upper Map Pocket
Lower Map Pocket
Lower Substrate
CLASS C SURFACE
- The Class C surface is used to bind the Class A and Class B surface together in order to form a closed surface.
Arm Rest
Upper Map Pocket
Lower Map Pocket
Lower Substrate
PROCEDURE
CREATING TOOLING AXIS
- Initially the given Class-A surface was imported and checked for any discrepancies in the boundary and performed draft analysis on it at 3-degree draft.
- The ejection from the mould after manufacturing the interior trim must have the nominal 3-degree draft angle.
- Extracting the flat surface, creating a line normal to that surface and consider it as a Main Tooling Axis.
Arm Rest
Upper Map Pocket
Lower Map Pocket
Lower Substrate
CREATING CLASS B SURFACE
- First offsetting entire class A surface to 2.5mm in the inward direction as 2.5mm is thickness of component.
- Some of errors were created in the offsetted surface like incomplete surfaces, gaps, small patches.
- These errors were solved by extracting surfaces, join by sub-elements to remove, extrapolating, sweep, multi-section surfaces etc commands.
- Joining patched surface to main surface, Class B surface was created.
Arm Rest
Upper Map Pocket
Lower Map Pocket
Lower Substrate
CREATING CLASS C SURFACE
- We first extract the edges from the Class A surface with the help of the multi extract command which we create the path for a sweep for class C.
- Create a sweep with reference to the curve and the reference surface with a 90-degree angle and with draft direction where ever required and give the inside direction Check for the continuity of the surfaces if there is any gap go for extrapolated and trim all together now, we will get the class C surface.
Arm Rest
Upper Map Pocket
Lower Map Pocket
Lower Substrate
- Joining class-A surface and class-C surfaces together.
Arm Rest
Upper Map Pocket
Lower Map Pocket
Lower Substrate
CREATING SOLID BODY
- Later, Joined Class A & Class C surface is trimmed with Class B surface to form the A pillar surface.
Arm Rest
Upper Map Pocket
Lower Map Pocket
Lower Substrate
- Using the surface created, the solid plastic component was obtained using the Close surface feature present in the part workbench.
Arm Rest
Upper Map Pocket
Lower Map Pocket
Lower Substrate
- The Tooling axis, side core axis, Class A, B and C surfaces were published.
B SIDE ENGINEERING FEATURES
LOCATORS
Any workpiece has 12 degrees of freedom for movement in space that consists of 6 Axial and 6 Radial Degrees of Freedom. All 12 degrees of freedom must be restricted to ensure proper referencing of a workpiece. These 6 Axial Degrees of Freedom permit Straight-Line Movement in both directions along the 3-principal axis shown as X, Y & Z. The Radial Degrees of Freedom permit Rotational Movement, in both Clockwise & Counter clockwise radial directions around the same three axis.
2-Way Locator
These are the locators which arrests 2 degrees of freedom by a single rib.
4-Way Locator
These are the locators which arrests the 4 degrees of freedom by four ribs junctional together. These are of following type especially used for mould designs.
HEAT STAKES
Heat Staking is a pulsed-heat process to join two or more parts out of which one at least is made of plastic. The process is to deform the plastic material using heat and force at a set process time. The bond is made by partially de-forming the plastic part in order to fix the other. Heat Staking makes it easy to bond metal to plastic and is commonly used in high volume/low-cost applications such as automotive, IT and consumer appliances.
DOG HOUSE DESIGN
Dog house is an engineering feature used in the plastic trim design. Dog houses are used as supporting features. Sometimes other engineering features like snaps; locators, etc. are mounded on them to increase their Height. Dog house and other engineering Features are built on B-surface.
Design rules for Dog house creation:
- "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
PUSH PINS
DRAFT ANALYSIS
- First, we should change model into material mode.
- Go to insert and in analysis select feature draft analysis.
- Align the compass along tooling axis and lock it.
- Next click on the surface and see that the surface is within the permissible limit of the values.
- The green colour area shows that it satisfies the 3-degree draft angle. If not satisfied then by using the Running point tool the area is measured and then altered to get a successful draft for the created tooling direction.
Arm Rest
On given Class A surface
On obtained PART BODY
Upper Map Pocket
On given Class A surface
On obtained PART BODY
Lower Map Pocket
On given Class A surface
On obtained PART BODY
Lower Substrate
On given Class A surface
On obtained PART BODY
CONCLUSION
- The creation of Tooling axis, Side core axis and Draft analysis were performed.
- The solid component was created from the surface geometry as per master section provided.
- The necessary screenshots and files were attached.
- The Class A, B, & C surfaces and also the Tooling Direction have been Published.
- Given push pin clips were assembled on dog houses and final door trim panel assembly done.
