Week 8 - Challenge 2 - Base Bracket Design

Objective:

To check and analysing the draft angle of given class A surface and determining tooling axis.

Creating Class B, C Surface to complete the base bracket model and develop solid part body with plastic design standards.

Draft Analysis:

In molding process the molded parts have to eject from the die so there is some issues while removing the molded parts it may get sticky with the die or while removing chances to get damage, so what we need to setup is the draft angle this draft angle helps the molded parts to eject from the die easily, for the plastic components the general draft angle should be in minimum 3deg. and if it is sheet metal component 7 deg. should be the draft angle, This draft is get analysed and ensuring the part is with proper draft angles.

Tooling Axis creation:

The tooling axis is basically the direction that the mold pulls apart. The mold is built in two separate pieces, basically. It has a Cavity side and a Core side. The Core pulls apart from the Cavity along Tooling Direction which is tooling axis.

So, when we add in your ribs, maybe some pockets, walls, whatever that may be bosses, the walls are going to be drafted based off of the Tooling Direction. It's to make sure that the Core can pull apart from the cavity, nice and clean.

Steps to find the tooling axis and determining drafting analysis.

A. Steps involved in creating TOOLING AXIS:
1. Create an Axis system at the center of the hole as shown in figure.

2. Create an intersecting curve (using YZ-plane and the Class-A surface of BASE BRACKET)

3. Create two line on draft side and derive bisected line. Bisected line is tooling axis.

4. Creating Class A Surface.

5. Creating Class B surface which is 2.5mm offset from class A surface.

6. Create class C surface which connect class A to Class B surface.

7. Triming Class A, B & C surface to form close surface and developing solid body.

8. Solid Body

9. Draft analysis.

Green Colour represent  all surface of body meets minimum 3 degree draft angle and red face represent less than 0 degree angle of draft angle which act as core side in injection mold assembly.

Feature Tree

Conclusion:

Hence tooling axis derived for given cstyling surface and using it class A,B & C surface are developed considering plastic standards and verified with draft analysis.