Week 12- Final project
- Development of a Door Trim panel
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Creation of CAD model considering following inputs as like in OEM and tier1 companies
- a) Class A surface
- b) Nominal thickness : Refer master sections
- c) Attachment strategy :
Find a attachment strategy for the door panel complete work.
Use Push pin with Dog house for Lower substrate – Door panel attachment
Use heat stakes for part to part attachment
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GIVEN INPUT
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DESIGN LIFE CYCLE
It Involves
Concept sketches
Class A creation
Clay modeling
NPD CAD
Concept sketches which are fed into computer as 2D sketches
Class A: The dedicated Class A Surface creation software helps turn a sketch into a surface that can be controlled in a three-dimensional virtual space. One would typically require three images, i.e., the front view, side view, and top view.
Class A and clay modeling are inter related. Clay model is the one to one model of vehicle both interior and exterior would be made for realistic display.
NPD CAD – New product development is where the designing parts for assembly with dimensions takes place.
Now we are going to work in new product development phase for the given Input.
- nterior Trims are manufactured by Poly propylene (PP), Acrylonitrile butadiene styrene (ABS), Poly vinyl chloride (PVC).
Since plastic in light in weight, economic effectiveness wide variety of plastic are used. It also gives good aesthetic surface.
CLASS A CREATION
From the given Input the respective class A class A surface are created by joining the surfaces. Check for continuity of the surface.
Now the parts which we are going to work is
Door Arm Lower substrate and Map Pocket
And the master section for attachment feature creation.
Tooling axis Creation
Tooling axis is the direction in which the mold opens and closes. Also the areas which need to be drafted. To find the tooling axis analyze the part like walls and find the possible tooling axis .Tolling axis can also be created by bisecting method.
Now for the door arm the tooling axis is created in Z direction. The slider axis is also created for the purpose drafting. Door arm is taken as two parts.
For Lower substrate the tooling axis is taken in Y direction.
For Map pocket in y direction.
B SURFACE CREATION
B surface is the engineering surface where all the b side features like rib, dog house screw boss, and locator and heat stake are designed.
The class A surface is offset to 2.5 mm to get the b surface.

C SURFACE CREATION
C surface is the surface which connects the A surface and B surface along the tooling direction.
In door arm 1 the class A boundary is swept with reference to the surface and door arm is swept in direction of tooling axis.
In lower substrate the class A and B surface boundaries are multi sectioned and A-b-c surface are joined together to get a closed surface.
In map pocket the swept is done in draft direction.
After c surface creation class A, B and C surface are joined together to get a closed surface.
To check click boundary and see whether boundary is forming, if it is showing error then we got a closed surface.
Then switch to part design and given closed surface to form the solid part body.
Then closed surface command is given to get the solid body in which the b side features are created
B SIDE FEATURE CREATION
For the attachment strategy master section is given from which we have to create the b side features at respective surfaces.
Master sections are the guides for the design requirements which decide the component packaging after technical surfaces.
During the period of vehicle concept design, the evaluation of master section performance depends on reference vehicle data and the experience of structure design engineer
In door trim panel we are going to create heat stakes, dog house, Flanges and ribs
Ribs: Ribs provide a means to economical stiffness and strength in molded parts without increasing overall thickness. They also facilitate locating and arresting components of an assembly, provide alignment and act as stops or guides for mechanism
Heat stakes: Heat stakes are used to join components of similar or dissimilar material.
Thermal staking is an assembly method that uses the controlled melting and reforming of a plastic or metal component of an assembly in place. The plastic stud protrudes through the hole in the component to be locked in place.
Dog house: Dog house is an engineering feature used in plastic trim design which is used as a supporting feature. Other features like locator are mounted on them to increase strength. They prevent breakage of the component during ejection.Ribs are given for dog house. Push clip is mounted on the dog house .
the sketches are drawn with positiones and iso constrained.
Drafting: Draft is providing angles or tappers on product feature such as walls, ribs and bosses that lie parallel to the direction of release from the mold that eases part ejection.
Adding draft helps the part to release. Most parts or applications require a minimum of 0.5 degree to 1 degree however 3 degree is widely accepted as the norm.
Ideal draft for a component is 3 degree.
Minimum 0.5 degree is accepted in b side features.
Draft analysis is done along the tooling axis for class and final part body.
change the view mode to customize view parameters mode -then go to inser -analysis-feature draft analysis.Place compass on the respective tooling axis.Th draft analysis is formed.green above 3 degree blue 0-3 degree red -negative draft

