Week 9 - Challenge 1 - Base Bracket Design

Aim:- Create the Base Bracket Plastic component through the given Class-A surface. To begin with, the tooling axis for the given Class-A Surface should be created meeting the requirements of the draft angle and at the end perform the Draft analysis on the model. 

Reference:- We have an given surface using this have to create Tooling axis, draft angle & draft analysis of the base bracket model. 

Objective:-

1. Tooling Axis.
2. Draft Analysis of Class A surface.
3. Creation of class B & class C surface Using given class A surface. 
4. Creation of Soild model of surface.
5. Analysis of final plastic model to class A surface.
6. Publications: Use the publication option and publish the below
   • Tooling Axis.
   • Class A, B, and C surface.

Tools used:- Following tools were used to reach the final step, 

1. Extract
2. Un-trim
3. Trim
4. Extrapolate
5. Offset
6. Edge fillet
7. Boundary
8. Sweep
9. Join
10. Close (part design)

1.Tooling Axis:-

     Its direction in which the mold or core and cavity opens is the tooling axis. Also its predefined the feasibility of componenet very easily. For tooling axis following points to be consider. 

• First ensure the class-A surface is properly joined and has no discontinuity on it. For this we can use boundary command or join command.
• Analyze the model manually or visually to see which direction is most suitable for tooling axis.
• As in 3D view we can see 2 holes and a flat surface, we can directly take the tooling axis perpendicular to that. But to be sure,let us analaze from all the views. The below images of the front side and top views shows the areas that we have to keep in mind while choosing tooling axis. As from X we cannot see one hole so we cannot take axis along this. In Y we cannot see any holes so here too we cannot take tooling axis. But in Z we can see 2 holes and flat surface so we can take tooling axis.             

Intersect the ZX plane of the axis system with the input and we can see that there is no surface that can create problem during tooling in this direction.                                   

Intersect ZY plane and we are unsure of these two surfaces, so we make a line and bisect them both and this will be our tooling axis which, not so surprisingly, is the same as our guessed tooling axis. 

2. Draft Analysis for Class A surface:-

    The Draft Analysis allows the user to easily analyze a part for proper draft angle. A Draft Angle describes the amount of taper for molded or cast parts perpendicular to the parting line. the given angle for draft analysis in plastics mold design is 3 deg, also its pre-define the feasibility for plastic models. 

The given picture shows below zero of the 3 degree called as positive draft of above of the degree called as negative draft.

3. Creation of class B & class C surface Using given class A surface:-

FOR CLASS-B SURFACE:

We can divide the surfaces as shown below. Then we will work on them one by one.

FLAT SURFACE:

1. Extract the flat surface.
2. Un-trim the surface.
3. Extrapolate it.
4. Offset it by 2.5mm i.e. thickness.

SLANT SURFACE:

1. Extract the slant surface.
2. Un-trim the surface.
3. Extrapolate it.
4. Offset it by 2.5mm i.e. thickness.

RIBS SURFACES:

1. Extract the rib surfaces (1 rib at a time).
2. Un-trim the surface.
3. Extrapolate it.
4. Offset it by 2.5mm i.e. thickness.
5. Trim to get the desired shape.
6. Repeat it with the second rib too.

Once we have finished doing this, we have to trim the surface to get exact shape of the class-A surface (without fillet) below 2.5mm. After the trimming part is done, fillet the model. Formula for filleting= fillet value+thickness (if the surface is below). We get our class-B surface.

FOR CLASS-C SURFACE:

1. Extract the boundary of the class-A surface. 
2. Extract the boundary of the holes on the class-A surface.
3. Use sweep command on the boundaries one by one to get the class-C surface.

FINAL BASE BRACKET:

Join the class-A and class-C surfaces together.

5. Analysis of final plastic model to class A surface.

 

Conclusion:- In this way we have successfully complited the given challenge by using Class A surface.