Week 9 - Attachment Feature Creation - Challenge 1

AIM

Create the rib for the Centre console coin holder considering the design rules as mentioned in the below image.

OBJECTIVE

• Create a Rib for the CoinHolder following Design Rules for Rib creation.
• Perform Draft analysis.
• Arrange proper tree structure.
• Geometrical sets should have a proper name based on the sketches present inside of it.
• All the sketches should be created under the Geometrical set.

RULES FOR RIB DESIGN

STEP-1

DESIGN RULES

• Nominal wall thickness of a plastic component: 3mm
• A deviation of +-30% from the wall thickness is accepted
• Ideal draft for a component is 3 deg
• Minimum of 0.5 deg acepted in ribs

STEP-2

RIB DESIGN

Rib provides means to economical stiffness and strength in mod parts without increasing overall wall thickness.

• Locating and arresting components of an assembly
• Providing alignment in mating parts
• Acting stops and guides for maechanisms

CREATING MORE RIBS

• Taller Ribs are prone to buckling under load.
• In those condition consider designing two or more shoter, thinner ribs to provide same same support with improved mold abillity
• Condition for addition rib as per the image shown below:

Guide Lines for Ribs on Show Surfaces

1. Draft - 0.5 deg per side minimum
2. Thickness - Base Thickness of the rib at tangent of radius(w = .4*T(wall thickness))
3. Height- Depth of the Rib (<= 5T)
4. Spacing - S>=2T
5. Thickess at Top - Minimum thickness at Rib Tip - .75mm
6. Optional Radius - .25mm maximum

Design Suggestions -

• Do not want to signficantly increase rib thickness
• Most not violate 40%*thickness requirement
• Root Thickness can have deviation of 30% of wall thickness.

PROCEDURE

STEP -1

Sketch for the length of rib.

STEP -2

Extrude the sketch for 5*Thickness of the component which is (5*2.5 = 12.5mm).

STEP -3

Thickness of the rib should be .4*Thickness of the component(.4*2.5 = 1).

STEP - 4

Giving Draft to the Ribs from four sides of .5 deg from base.

STEP - 5

Assmeble the Rib part body inside the main part pody and then give edge fillet to all faces of rib for .25mm.

STEP - 6

Creating More Ribs

Height/Width (mm )= 3:1

12.5/Width = 3

Width = 12.5/3

Width = 4.1 ;(Width should be>3)

Here we can take 5mm for the width.

• Repeat Step 1 to Step 5 to create more ribs.

STEP - 7

Creating intersection between the reference Plane in XY Direction and component part body.

STEP - 8

Checking for proper measurments according to the design rules.

PROCEDURE FOR DRAFT ANALYSIS

1. Changing view mode to material mode in Mesh.
2. Toolbar>Insert>Analysis>Feature Draft Analysis
3. Drag the compass from dialogue boc to the Tooling axis and place propely.
4. Click anywhere in the component and click ok.
5. Analysis the colour of failing and passing surfaces.
6. Gren colour means draft is upto the desired and component is ready for maufacture
7. Blue means zero deg and red means below zero deg(Because of reverse direction).

TREE STRUCTURE

CONCLUSION

Creation of Rib on Coin Holder has been successfully done by following all the design rules and the Tooling axis has been created following OEM standards.