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

DRAFT ANALYSIS:

THIS AIDS IN UNDERSTANDING WHETHER OR NOT THE PART TO BE MOULDED CAN EASILY BE REMOVED. THE FACES THAT ARE DRAFTED RENDER THE PART TO BE REMOVES EASILY DURING THE EJECTION PHASE OF INJECTION MOULDING.

TOOLING DIRECTION:

THE TOOLING DIRECTION IS DETERMINED BASED ON THE DRAFT ANALYSIS CONDUCTED W.R.T THE TOOLING AXIS. IN ESSENCE, THE AXIS THAT ALLOWS ALL THE RELEVANT SURFACES TO HAVE THE DESIGN DRAFT

ONE OF THE DESGIN PRACTICES TO BE NOTED IS THE REFERENCE OF THE GLOBAL COORDINATE SYSTEM IN THE MAKING OF THE TOOLING AXIS. THIS HELPS TO KEEP A STANDARD THROUGHOUT THE DEVELOPMENT OF THE VEHICLE FOR THE OEM.

A DUMMY TOOLING AXIS IS CREATED IN THE Y AXIS OF THE AXIS SYSTEM (SAME AS GLOBAL CSYS)

THE DRAFT ANALYSIS IS CONDUCTED FOR THIS GIVEN TOOLING AXIS WITH THE MINIMUM DRAFT ANGLE OF 0.45 DEGREES AS THE GIVEN CLASS A SURFACE INTRINSICALLY DOESN'T ALLOWS FOR THE MINIMUM 3 DEGREE DRAFT.

HENCE THE TOOLING AXIS CAN BE PROCEEDED WITH

ISOMETRIC:

FRONT:

SIDE:

TOP:

RIB ROOT THICKNESS ANALYSIS:

THE DESIGN RULES SUGGEST THAT THE MAXIMUM THICKNESS AS FUNCTION OF THE NOMINAL WALL THICKNESS SHOULD BE 1.3 TIMES. THIS MEANS FOR W = 2.5MM; MAX W = 1.3 X 2.5 = 3.25MM.

THE RIB ROOT THICKNESS FOR OUR CASE IS 2.68MM WHICH CLEARS THE DESIGN RULE.

NOTE: THE HEIGHT TO DIA RATIO FOR THE SCREW BOSS IS LESS THAN 3. FOR THE ASSUMED M4 SCREW BOSS, DIA = 4MM.

HENCE, THE SCREW BOSS HEIGHT IS 12MM.