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

Door Handle's Ribs and Screw Boss Report

Aim :

• To create Tooling axis and Conduct Draft analysis for both the Class A and Final Solid part.

Objective :

Ribs and Screw Boss Report:

• To create the Final Solid Part by using the given Class A.
• To create the Tooling Axis.
• To create the Ribs as per the design rule.
• To create the Screw Boss as per the design rule.
• To Draft analysis the obtained Final solid part, Class A, Ribs and Screw bars using the created Tooling Axis.

Introduction :

Tooling Axis:

• The Tooling Axis is to show in what direction does the core and cavity moves.
• It also created to give a draft angle for the final solid part.

Draft Analysis:

• The draft analysis is done on the basis of the Tooling Axis in order to find whether the final product is done as per the Design rules.
• The Draft angle which is assigned to the Tooling Axis defines the analysis.
• The Nominal Draft angle for the plastic product is 3 degree.

Class A:

• Class A is the aesthetic surface.
• Class A is created on the basis of a concept sketch or by the predefined shape on basis of the design engineer and customer requirement.
• Class A is given to the Product design engineer in order to get the final solid part.

Class B:

• Class B is the surface that is created by the product design engineer in order to get the final product from the class A surface.
• Class B is created based on the thickness that the final solid part should be.
• In other words, Class B is an Extended version of Class A with some thickness gap between them.

Class C:

• Class C is the surface that is designed by the product design Engineer.
• Class C is created inbewteen Class A and Class B in order to connect them.

Ribs:

• Ribs are thin, wall-like features typically designed into the geometry of a part to add internal support to walls or other features like bosses.

Screw Boss:

• The Screw Boss is cylindrical-like feature where its support the geometry for postioning the screw.

Procedure :

Class A:

• The class A is taken from given Step file.
• Created class A is checked with the boundary tool.

Tooling Axis:

• The tooling for this can't created by using bisecting method.
• The tooling is created here by Axis method.
• In this the axis is selected where all the feature in the class A is clearly visible.

Draft Analysis on Class A:

• The draft analysis is done on class A with the help of tooling axis.
• As you see in the below the given Class A is not correct.

Class B:

• The Class A is offseted to given 2.5mm.
• Then fillet which are not forming is created.
• Thus Class B is created.

Class C:

• The class C formed by creating boundary and extract edge from class A.
• Class C are created in sperate patches.
• They are extrapolated and then trimed.
• Then in some areas joined together.
• Thus Class C is formed.

Final Operation:

• The Class A and Class C are joined together.
• Then joined Class a and Class C are trimed together to form a Closedsurface.

Solid Body:

• The Closed plastic surafce is converted to solid by using 'closesurface'.
• Switch from 'Generative surface design' to 'part design' to do it.

Draft Analysis of Solid:

• The draft analysis on solid body is done.
• The draft analysis show the created solid is not correct due to error in given class A.

Ribs :

• Ribs are B-side feature which support the main body.
• As per given reference ribs are created.
• The extracted plane and point used for tooling creation are used to create the sketch for ribs.
• The sketch drawn is iso-constrained.
• Then the ribs are extrude to the height which are calculated.
• The extrude is converted to solid by using Pad.
• In pad 'thick' option is used.
• The ribs are then drafted to 0.5 degree.
• The fillets are applied to of radii 0.25 mm.
• The Ribs are then union trimmed with the Created solid body.
• In the uniontrim 'keep body' is selected.
• The 'Edge fillet' is given to the ribs on the joining edges.
• Same procedure is followed to create the second rib.

Screw Boss :

• The Screw boss is also a B-side feature which support the main body.
• The extraction is created and the 'on surface ' in point tool used to create point.
• The Screw boss is designed for M6 thread.
• The Sketch are drawn based on the M6 thread requirement.
• The sketch drawn is iso-constrained.
• The drawn sketch is pad to height as per the design rule.
• The pad Screw boss is draft to 0.5 degree.
• The Screw Boss is drafted on both side.
• Then Support ribs created for the Screw Boss.
• The suport rib is created as per the design rule.
• Then created rib is draft to 0.5 degree and filleted to 0.25mm.
• The support rib is then union trimmed with screw boss.
• In union trim the remove body option is selected and inner part inside screw boss is selected.
• The Union trimmed Screw boss is again union trimed with main body.
• In it keep Body is selected and required body is selected.
• Same procedure is follwed for the second Screw Boss also.

Final Draft Analysis :

• The draft analysis for final solid body with ribs and screw boss is done.
• As mentioned above the Class A is Not Correct so resulting Draft is not correct.

Conslusion :

• The given Class A is not correct so draft analysis which derived is wrong.
• All other Class B, Class C, Ribs and Screw Boss are created as per design rules.