Week 8 - Challenge 2 - Switch Bezel Design
SWITCH BEZEL DESIGN
AIM: To create the Switch Bezel Plastic component through the given Class-A surface by creating a tooling axis meeting the requirements of the draft angle and to perform the Draft Analysis on the solid model at the end. The Thickness of the component is to be taken as 2.5mm.
GIVEN CLASS A SURFACE:
The Class A surface is given to us as an input consisting of different parts which are combined to form a single Class A Surface using the Join command. A merging distance of 0.003mm is given as input in Join definition to form the Class A without any open edges inside the geometry. The open profiles for the Class A are checked using the Boundary command.
EXPANDED TREE STRUCTURE:
REPORT ON DRAFT ANALYSIS AND TOOLING AXIS CREATION:
DRAFT: It is the degree of taper that is incorporated into the side wall and cores of the die cast tool to aid in the removal of a part. Primarily, they function to reduce the friction between the part and the tool as it is ejected. Without draft angles, parts can be stripped, dented, or get stuck in the tool.
The Draft Analysis command enables you to detect if the part you drafted will be easily removed. In the case of plastic injection molded parts it also allows the designer to see if there is enough draft on the part to ensure that it can be correctly grained.
TOOLING AXIS CREATION:
Tooling axis is the direction that the mold pulls apart. It is necessary to create a tooling axis to give draft to the component. Tooling axis is created using the Bisecting Method. For the given Class A surface, the best tooling direction for the component is chosen by considering the tooling of the final product. It is chosen in such a way that the component is cleared with minimum tooling.
BISECTING METHOD:
For a given specific direction, it is found that the given component is clearing the tooling in Z direction. On the Class A, a point is created at the geometric centre of the base using the "surface type" in point definition. An axis system is then created with the point as origin.
Then a bisecting line for the two opposite walls is created in YZ plane by intersecting the 3D elements in the positioned sketch.
Since there is no opposite wall for the other vertical wall, a line is created using positioned sketch in the XZ plane with an angle to the intersection line of the 3D element with the origin as starting point. The angle taken is 6 degrees by trial and error.
Now an other line bisecting the two lines is created using the 'Bisecting Type' in life definition. The inputs given for this bisecting line are the two previous sketches and the center point.
This line thus created is the main Tooling Axis of the component.
The line is renamed as Tooling axis and is then published for easy accesibility. This is the process for creating a Tooling Axis using Bisecting Method.
DRAFT ANALYSIS ON CLASS-A SURFACE:
Draft Analysis is performed on the Class A Surface after creating the Tooling axis. It is performed to check if the surface clears the tooling.
From this Draft Analysis, it is clear that a minimum draft of 3 degree is maintained for the Class A surface as the colour 'green' indicates that the surface passed the draft check which can be seen from the colour scale table. The second picture shows the Full Draft Analysis of the surface with color scale table.
Thus we can conclude that the Class A Surface clears the minimum required draft for tooling.
FINAL SOLID MODEL:
After trimming and joining all the three Class A, B and C Surfaces, the final solid model is created in the part body using the Close Surface tool in the Part Design workbench. This is the required solid component - Switch Bezel.
DRAFT ANALYSIS ON SOLID MODEL:
Draft Analysis is done on the Solid Model using the "Draft Analysis" command in the Analysis toolbar. The compass option in the tool is used to define the current draft direction. Click the option and bring the compass on the body and align its axis with that of the Tooling Axis. Then lock the draft direction using the lock option in the tool. After defining the draft direction, the part body is selected and the colour scale icon in the display bar of the tool is turned on. The quick analysis mode is turned on to see the color sclae.
QUICK ANALYSIS MODE:
From this Draft Analysis of the solid part, the surfaces of the part body can be seen clearing the tooling for a minimum of 2.9 degrees of draft. Whereas when the clearing check is increased to 3 degrees, the end surface can be seen not clearing due to deviation as shown below. So, a draft check of 2.9 degree is feasible.
A detailed draft analysis color scale table of the solid part is provided below. It can be obtained by selecting the Full analysis mode in the tool.
FULL ANALYSIS MODE:
DRAFT ANALYSIS ON SOLID MODEL IN VARIOUS ORIENTATIONS:
ISOMETRIC VIEW:
FRONT VIEW:
SIDE VIEW:
TOP VIEW:
