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

Door Handle (Rib & Screw Boss Attatchment)

Aim -

• To create the Door Handle Component from the given Class-A surface.
• To attach B side features, ribs and screw bosses,in the component.
• To perform the Draft analysis on the model.

Take the thickness of the component to be 2.5mm.

Design Procedure (Door Handle) -

1. Check the Class A surface for discontinuities. Create a suitable tooling axis with a flat surface as reference.

2. Offset the Class A surface by 2.5mm inwardsa to get the Class B surface.
3. Check for discontinuities on the Class B Surface, repair the surface if errors are found.

4. Create the Class C surface with the sweep operator.
   - Use the draft axis as the reference for the swept surfaces parallel to the draft axis.
   - Use the Class A surface as the reference for the swept surfaces perpendicular to the draft axis.

5. Join the Class A and C surfaces. Extrapolate the Class B surface so that it intersects with the Class A&C join.

6. Trim the Class A&C join with the Class B surface to get the hollow closed surface.

7. Use the close surface command in part workbench to create the solid part body of the Door Handle.

Design Procedure (Ribs) -

Ribs are thin extensions that run perpendicular to a surface from the wall of the component. They are used to provide additional support and strength to the part.

1. Create an iso-constrained sketch on the surface/ plane on which the rib will be constructed.

2. Add a new Body and Pad the Sketch to for the rib’s profile.
3. Add a draft of 0.5deg to all the required surfaces.
4. Create the required number of ribs in a similar way or use the copy-paste-translate commands.

5. Union trim the rib to the Door Handle Surface.

Design Procedure (Screw Bosses) -

Screw Bosses are used to provide channel for screws to attach additional components or to fix the component to another with screws. Smaller ribs are used to strengthen screw bosses.

1. Create an iso-constrained sketch on the surface/ plane on which the Screw Bosses will be constructed.

2. Add a new Body and Pad the Sketch to get the screw boss’ profile.
3. Create a sketch for smaller ribs that should support the screw bosses, pad and form the ribs with appropriate height.

4. Add a draft of 0.5deg to all the required surfaces.
5. Union trim the rib to the screw boss.

6. Create the required number of screw boss components in a similar way or use the copy-paste-translate commands.
7. Union trim this component to the Door Handle Surface.

Tree Structure -

Final Part Component -

Isometric View :

Front View :

Top View :

Side View :

Draft Analysis -

The optimal Draft Angle is found to be 0.95deg from the given Class A Surface.

The optimal Draft Angle for attachments should be a maximum of 0.5deg.

Class A Surface :

Door Handle Solid Part :

Rib Attachment :

Screw Boss Attachment :

Result And Conclusion -

• The Door Handle component is designed and the Ribs & Screw Bosses are attached according to the requirements.
• Draft Analysis is done on the Class A Surface, the Solid Surface developed from the hollow closed surface, The rib attachment, the screw bosses attachment and the final Door handle part. The results all pass the inspection.