Week 9 - Attachment Feature Creation (Ribs & Screw Boss) - Challenge 1

• Sketches
• Used Position sketch
• Sketches are Iso-Constrained
• Tree Structure
• Proper Tree Structure
• Geometrical sets are proper name based on the sketches present inside of it
• All the sketches are created under the Geometrical set 

Creating the ribs for the Drill Handle considering the design rules

 Objective:

           The Objective of the project is to Create Ribs and Screw boss for drill Handle considering the design rules and also Draft Analysis by Creating the tooling direction for given Class A Surface. and Thickness of the component is 2mm.

Introduction:

The Draft Analysis command enables you to detect if the part you drafted will be easily removed. This type of analysis is performed based on colour ranges identifying zones on the analyzed element where the deviation from the draft direction at any point, corresponds to specified values.

               Tooling direction is the main consideration for plastic part and mould parts because it defines the movement of the mould part and the possibility of the plastic part coming out from the mould part (Core and Cavity).

Tooling Direction:

• Tooling direction is known as primary direction. In Molding, machine arrangement is given to open the mould along a direction which is known as Tooling Direction. In other words. The mould is built from two separate halves (Core and Cavity) and tooling direction basically defines the direction of mould pulls apart.

Procedure for Creating Tooling Axis:

• First, the given styling surface was imported into CATIA and checked for irregularities by using Join, Boundary and Disassemble option.
• Then Make a point on the surface and create line for Tooling Axis. Here i did't used bisecting lines.

Publications:

The tooling axis and class-A surface were published for further easy reference, from Tools – Publications.

Performing Draft Analysis:

• For plastic parts, the nominal angle value for draft analysis is 3 degree but even a 0.5-degree angle can be created for sub-assemblies like ribs and slots. (For Sheet Metal 7 degree angle is the nominal value)
• Insert – Analysis – Feature Draft Analysis
• Draft analysis was carried out by pulling the compass to the tooling axis and an inverse draft axis was carried out if required.
• After setting the compass over the tooling axis the compass must be locked to a specific direction.

• If the surface was in green then the model passes or else further operations need to be carried out.
• By using full analysis mode detailed analysis can be carried out for complicated assemblies.
• By using the analysis under the running point complicated parts and surface were checked in detail.

Creating Ribs for Drill Handle:

First have to thicken the class A surface for 2mm then go for rib creating.

• Hight of the rib is 5 times of thickness so 2mm is the thickness X 5 times = 10mm.

• Rib Thickness is 0.4 * t so 0.4 * 2 = 0.8mm
• t is thickness of drill Handle

• Given 0.5 Deg draft angle for Rib. and 0.25mm fillet radius and also Intersection checked.

Creating Screw Boss for Drill Boss:

•  Draft  - 0.5 degrees on the walls of boss
•   Thickness -  Typically 40%* of the nominal wall at the base.
•   Height to Diameter Ratio -  3:1
•   Radii - 0.25mm maximum radii.  
  

• Creating for M4 Screw Size so i took 3.2mm inner dia and wall thickness is 0.6mm and drill handle thickness is 2mm so 2 X 0.6 = 1.5mm per side so 3.2mm + 3mm = 6.2mm is the outer dia

• 0.5 Deg Draft angle for Screw boss and 0.25mm Fillet Radius.

Draft Analysis for Solid Drill Handle:

Feature Tree:

Conclusion:

            The Ribs and Screw boss for Drill Handle considering the design rules has created successfully.