Week 8 - Challenge 2 - Base Bracket Design
DRAFT ANALYSIS OF BASE BRACKET
Objectives:
To create Class B & C surface from Class-A surface
To create tooling axis for the model
To perform draft analysis on given Base Bracket model
To generate solid part from surface model of Base Bracket
Steps of creation of tooling axis and Class-A surface of Base Bracket model:
Create a Class-A surface of Base bracket by connecting different surfaces using JOIN or BOUNDARY command. Class-A surface will be seen yellow as shown in figure.
If any green line is seen on surface it means discontinuity exists. To remove all discontinuity use FILL option.
After joining this model, a tooling axis needs to be created.
Tooling axis is used for drafting analysis purpose. If some inclined surfaces are present in model, there are chances of failure while applying draft on them. So tooling axis is created along intersection of these similar surfaces.
First, locate center of hole and create a dummy tool axis along Z direction.
So create an intersection using YZ plane in direction of Y axis. Now, hide the given Class-A surface.
Here some inclined lines are available in this intersection sketch.
Two new lines are created on these lines and bisecting these two lines using reference of dummy tool axis, a tooling axis in Z direction is generated.
Here BASE BRACKET Class-A surface as well as TOOLING AXIS is published by using “PUBLICATION” from Tools menu.
Steps of creation of Class-B surface of Base Bracket model:
First, create Rib 1 (Right side) from Class A surface.
To create Rib 1, first use EXTRACT 3 faces from Class A surface. Then use UNTRIM for these faces.
Apply extrapolate to these untrims to generate extended surfaces by selecting boundaries & faces of them.
Now, use trim to remove unnecessary portions from these surfaces and offset these trims downside about 2.5 mm. Match the outcome with Class A surface.
Use above same steps to create another rib which is named as Rib 2, as shown in figure.
After creating those ribs, its time to create flat surface as well as surface between ribs.
Use extract to draw out selected portion of surface with hole. Apply 2.5 mm offset to it & then untrim it.
After this use extrapolate to enlarge this surface. Now trim it with two ribs to create a joined surface.
Now extract the flat surface. Give it 2.5 mm offset downwards & untrim it.
Trim it along above joined surface with ribs to create Base surface.
After trimming and giving edge fillet about of 3 mm, B surface is finally created.
Steps of creation of Class-C surface of Base Bracket model:
C surface is needed to connect class A surface and class B surface.
Here first create boundary of class A surface by using BOUNDARY option.
Now create a sweep surface by using sweep with draft direction. Use Tooling axis as direction line. Give 3 degrees draft to surface selected.
Create sweep for two holes given on surface by using sweep with draft direction.
Now, join B surface with these two sweep surfaces and create a C surface.
In part design workbench, use close surface to generate solid base bracket part from Class C surface.
Steps to do draft analysis on Base Bracket model:
Go to insert > analysis > feature draft analysis or directly click on Feature draft analysis icon from menu.
First select compass option from pop-up menu to set axis system coincide with tooling axis.
After setting up axis on tooling axis, use lock option to fix it.
Surface model will turn into green colour surface, which shows that draft for model is in limit upto 3 degrees.
Run quick analysis on model and if any draft angle is more than limit, then one can apply new value of it in pop up box.
Full analysis shows different draft angles with different colours as shown in figure.
Here is an example of INVERT DRAFT DIRECTION analysis.
Below image shows the different views of draft analysis of BASE BRACKET model.
Feature Tree images:
Conclusion:
In this challenge, I have learned about tooling axis creation, Class A, Class B & Class C surface creation and draft analysis for given BASE BRACKET model.