Week 9 - Project 1 - Door Trim Lower with Engineering Features

Objective:

• The tooling axis for the given Class-A Surface should be created to meet the requirements of the draft angle.
• Design the door applique plastic component through the given Class-A surface.
• Perform the feature Draft analysis on the model.
• Create the Heat Stakes and the locators considering the OEM design standard for the door applique.

Abstract: Design a door applique with b side features such as 2 Way, 4 Way locator, Heat stake with Counterpath clearance for door pannel using the CATIA V5 Surface workbench and to ensure that the product is manufacturable by injection molding. I received input as Class A Surface. I Check the direction to eject the tool based on the component design. Later I checked whether all faces that intersected will clear the direction based on the tooling axis. I started working on the Draft Analysis tool to check if our tooling direction clears the path for easy removal of material from the tool. After that, I go class B creation using Advance tools from the surface followed by class C creation using the sweep command. After designing A, B & C class surface, converting close surface into solid inside the part workbench. For b side features first created 4-way locator then 2-way locator and last create heat stake and make the clearance to the door panel.

Introduction:

Door Applique

A door applique is a decorative member or cover which is fastened to a vehicle surface to add styling and/or to functionally cover aesthetically non-pleasing portions of the vehicle. Conventional door appliques are made of metal and/or plastic as is known in the art. For example, it is known to provide appliques over the external surfaces of B-pillars of a vehicle (car, truck, van, or the like). While the applique may be attached directly to the B-pillar itself, it is also possible to attach a B-pillar applique to door sheet metal so that the applique is not directly attached to the pillar and instead opens and closes along with the door while the B-pillar remains fixed in place. A pillar is known in the art as a structural member provided to support the structure of a vehicle.

Heat Staking

Heat staking also known as thermoplastic staking is the process of joining two dissimilar materials together. In heat staking, we use local heating and cooling to raise the temperature of plastic components and allow plastic reforming to be carried out. This reforming can be used in a wide variety of applications.

Design Methodology flow chart

Procedure to find Tooling Axis

• Check for any openings in the given model Door Applique by using BOUNDARY. In BOUNDARY > select edges - select the surface to create the boundary at the openings.
• Create a point at the center of the surface by using Point Definition by Point Type - on the surface,Surface - select the surface, and Distance - 0
• By using the Line Definition option create a line in the Y direction by Line Type - Point-Direction, Point - select the point, and Direction - Y which will be the Main Tooling Axis.

Procedure for Creating B Class Surface

• Extract the plane surfaces from the class A surface neglecting the fillet surfaces.
• Untrim the surfaces from the extracted surfaces to get the actual shape of the surfaces.
• The Untrimmed surfaces should be intersecting with each other. If not intersecting extrapolate the surfaces.
• The thickness of the component is to be maintained at 2.5mm. So Offset the Extrapolated surfaces setting 2.5 mm as the offset value.
• Trim the surfaces as per the shape of the Class A surface.
• Create fillet for the component as per the class A surface. Measure the edge of the fillet value from the class A surface by extracting the fillet surface and untrimming the surface.
• Create fillets for the class B surface and make sure the thickness between the fillet surfaces are maintained the same as the remaining surfaces.

Procedure for Creating C Class Surface

• Extract the edge lines for the class A surface using multiple extract option.
• To create a sweep, there should be a boundary created to it. The boundary should be created separately as creating the boundary completely doesn’t create the sweep smoothly as the model contains the main unnecessary lines.
• To cover those, the smooth option is used to create the smooth surface and the Class A surface model is swept smoothly over the plane areas. Over the draft angled areas, the boundary should be created separately to create the sweep over that area.
• Create edge surface form class A surface using sweep option. Set the sweep mode to draft direction, select the extracted lines as guide curves and the tooling axis as the draft direction. Set the sweep angle as 3 degrees and the length of sweep more than 2.5 mm.

Now, the surfaces are then trimmed with a class B surface to form a closed surface.

Procedure for Closed surface

After closing A,B & C Class surface, change part design workbench and convert to solid body.

DRAFT ANALYSIS:

• Open the Draft analysis by Insert > Analysis > Feature Draft Analysis.
• Select the Compass - Direction in Draft Analysis and align it to the Tooling Axis and then lock it
• After locking it a cross symbol will occur at the pointer, select the surface and the surface selected turns into green.
• In Draft Analysis 2 box, select the green column to change the draft angle to 0.6 degrees.
• The color should be green in color.

B Side Feature used in door applique

1. 4-Way Locator
2. Heat Stake
3. Counterpath clearance for door pannel

Procedure for adding creating Locator

• Create a point at the center of the surface of Door Attachment by Point Definition.
• Create a plane on the surface at the center by Plane Definition with reference to the Point which was created and then create a sketch of a 4 way locator on the plane.
• Pad the Sketch in Part Design, in Pad : Type - to surface , Limit - select the surface as limit and Profile - Sketch and in Pad tick mark the “Thick” option and then click the more option and select the Neutral fibre and the thickness 1 should be 40% of the main wall thickness.
• Draft the faces of the padded area by Faces to draft - select the faces to draft , Neutral element selection - select the base surface and pulling direction - Tooling axis.
• After drafting the faces,chamfer the edges at the top and Objects to chamfer - select the edges , Mode - Length/Angle.
• Fillet the edges and faces.
• Copy the Part body of the 4 way Locator and Paste it Special with reference link and then Translate it to the other side by coordinates by Translate option : Vector Definition - Coordinates.
• Now create a 2 way Locator at below the center by creating a sketch and do the same process of Padding,Drafting,Chamfering and Filleting.
• By Boolean operation,Unitrim the Locators with the Solid body of Door Applique by selecting the faces to keep.

Procedure for adding heat stake

• Offset the Class A surface to 2.5mm and extract the boundaries of the offsetted surface.
• Parallel Curve the extracted boundaries by Parallel Curve Definition : Curve - extracted boundary, Support - surface , Constant - distance.
• Give the Points Repetition to the Parallel curves by Points and Planes Repetition by : Curve - Parallel curve, Parameters - Instances and Instances - no of points.NO Heat stakes should present nearer to Locators.
• Now create a sketch on the point created on a Parallel curve.Draw the circles with diameters of 5mm and 7mm and in Part Design,Pad it : Type - to surface , Limit - select the Class A surface.
• Copy the Part body of the Heat Stake and Paste it Special with reference link and then Replicate to the points which are created by Translate option : Vector Definition - Point - Point.Translate the part body of Heat Stake to the other point which was copied by selecting the start point and endpoint.
• By Boolean operation,Assemble all the Heat stakes part bodies in a single body and then Unitrim the Heat Stakes with the Solid body of Door Applique by selecting the faces to
• keep. The distance between the tip surface of locator and Door Attachment surface should be equal for all locators.Also the height of Heat stake should be smaller than the Locators.

Creating Clearance for locators and heat stake and thickness to door attachment surface

• Thicken the Door Attachment surface by Thicken option in Part Design by selecting the surface to thicken to 2.5mm.
• Now from the Locators sketch, copy the sketch into a new geometrical set and then draw a circle of 15mm and make the old sketch as construction lines where making the clearance for Locators.
• Pad the circle to an offset distance below the Door Attachment surface and draft the surface to 0.5 degrees.
• By Boolean operation,remove the Pad from the Thicken surface.So the clearance gap between the Locator wall and clearance wall should be 0.1mm to lock the motion.
• Do the same process for remaining Locators and Heat stakes by creating the Clearance gaps where the Clearance gap for Heat Stake should be 0.5mm.