Week 10 - Challenge 1- Attachment Feature Creation (Ribs & Screw Boss)

DESIGN OF RIBS AND SCREW BOSS

Ribs:

These thin-walled vertical features are often located inside a component, and can provide rigidity and strength to a part. Ribs can also support other features, such as bosses, and can be used as alignment features or standoffs.

Screw bosses:

These are used for screws or locators in assemblies, and are often exposed to stress.

Purpose:

Ribs:

· Reinforce flat areas.

· Improve rigidity and resistance to deformation.

Screw boss:

· Provide support for screws in assembly.

· Enable part alignment.

Design guidelines for Ribs:

· Draft - 0.5 degrees per side minimum

· Thickness Typically 40% wall thickness

· Height 5 x wall thickness

· Spacing 3:1-steel height / width ratio maximum

· Minimum thickness at Tip-.75mm

· Radii 0.25mm maximum

· Ribs on opposite side of wall should be offset.

· Ribs should be connected to other structural features where possible.

Design guidelines for screw boss:

· Draft - 0.5 degrees per side minimum.

· Spacing 3:1-steel height / width ratio maximum.

· Height 3 x wall thickness.

· Radii 0.25mm maximum.

· Thickness must smaller than 60% wall thickness.

Draft analysis of A class surface:

Draw a tooling axis on surface on Y direction.

Place the draft analysis compass in tooling axis.

It may show some blue indication .It shows that part must done by side core.

Design views of ribs and screw boss:

Specification ribs:

h=12mm

T=1mm

Radii of fillet=0.25mm

Specification screw boss:

h=7.5 mm

D_inner=5.2mm

D_outer=7.5mm

Radii of fillet=0.25mm

thus i have created a screw boss and ribs design.