Week 10 - Challenge 1- Attachment Feature Creation (Ribs & Screw Boss)
TITLE : TO CREATE PLASTIC MODEL WITH USING OF PLASTIC FEATURES (RIBS AND SCREW BOSS)
INTRODUCTION :-
IN THIS PROJECT WE CREATE CLOSE SURFACE OF DRILL MACHINE HANDLE WITH USING OF CLASS A OF HANDLE. FIRST IS THAT WE DO TOOLING AXIS AND DRAFT ANALYSIS.THAN SECOND WE GENERATE CLASS B AND THEN CLASS C, AND CRATE CLOSE SURFACE TO MAKE SOLID BODY OF GIVEN SURFACE. MOREOVER, WE ADD SOME FEATURE LIKE RIBS AND SCREW BOSS AND DO SOME CALCULATION.
OBJECTIVE :
1 AS PER THE GIVEN CLASS A SURFACE, CREATE 3D MODEL FOR PLASTIC PRODUCTION WITH USING SURFACE COMMANDS
2. CLOSE SURFACE MODEL MUST BE COVERTED IN TO SOLID MODEL
3. CREATE TOOLING AXIS FOR HANDEL
4. DO DRAFT ANALYSIS OF MODEL OF DRILL HANDEL AND ANGLE MUST BE MORE THAN 3 DEGREEE.
5. ADD RIBS AND SCREW BOSS WITH USING OF FEATURE RULE.
THEORY PORTION FOR PLASTIC
STEPS FOR MAKE PLASTIC 3D MODEL
1.INSERT CLASS A SURFACE - DESIDE TOOLING AXIS (FROM THIS AXIS WE CAN SEE ALL SHAPE ON THE SURFACE AND EASY FOR MAKING ) – USE DRAFT TOOL
2. AS PER THE CLASS A SURFACE WE MAKE CLASS B SURFACE (USE SURFACE COMMANDS)
- offset the surface to 2.5 mm from the class a surface
- after that some surface are not offset, these surface we create again.
NOTE :- FOR FILLET - UPPER SIDE FROM THE CLASS A - (THIKNESS - RADIUS = FILLET VALUE) EX.- 3 - 2.5 = 0.5
LOWER SIDE FROM CLASS A - (RADIUS + THIKNESS = FILLET VALUE ) EX;- 3 + 2.5 = 5.5
3. MAKE CLASS C SUFACE
- create extra surface for joining class A and B
- must follow minimum angle which is 3 degree .
4. SOLID BODY
- Join class A , B and C and build solid body
5. ADD PLASTIC FEATURE
- RIBS AND SCREW BOSS ARE ADD IN SOLID BODY (FOLLOW RULES OF PLASTIC FEATURE )
6.DO DRAFT ANALYSIS OF SOLID MODEL OF DRILL HANDLE (THE DRAFT ANGLE MUST BE MORE THAN 3 DEGREE --- WE ALSO SELECT LESS THAN 3 DEGREE BUT IT MAKE DEFFICULTY FOR PRODUCTION AND COST IS INCREASE)
CALCULATION FOR RIB
SOMETIME THICK RIB CREATE PROBLEM ON CLASS A SURFACE AND MAKE CRATE SINK MARK IN THE WALL, THEREFOR WE FOLLOW SOME DESIGN RULES TO GENERATE RIB.
RIB THICKNESS = 0.4 * WALL THICKNESS (2.5mm) = 1mm
HEIGHT OF RIB = 5* WALL THICKNESS (2.5mm) =12.5mm
RIB THICKNESS AT TIP ≥ 0.75MM (MINIMUM)
RIB DRAFT ≥ 0.5°
RIB FILLET RADIUS = 0.25 mm
RIB ROOT CHECK= CREATE CIRCLE WITH USING RADIUS CURVES AND wall BOUNDRY (THREE POINT CIRCLE) (CIRCLE REDIUS MIGHT BE SIMIRALE WITH WALL THICKNESS)
-HEIGHT(y) / WIDTH(distance between two ribs )(x)= 3:1
X= 12.5 / 3 = 4.1666 or more than 4
CALCULATION FOR SCREW BOSS
T= WALL THICKNESS = 2.5 mm
SCREW BOSS THICKNESS = 0.4 * WALL THICKNESS (2.5mm) = 1mm MINIMUM
INNER DIAMETER OF SCREW (D) = 5 mm
OUTER DIAMETER OF SCREW (D)= 10 mm
HEIGHT OF BOSS= 3T = 3*2.5 = 7.5mm
NAGETIVE HEIGHT OF BOSS = 0.3T= 0.75
BOSS DRAFT ≥ 0.5°
RIB FILLET RADIUS = 0.25 mm
3D MODELS IMAGES :
1.DRILL HANDEL MODEL
THIS IS THE PHOTO WHICH IS GIVEN BY THE INSTITUTE
TOOLING AXIS
DRAFT ANALYSIS OF BASE BRACKET
ISOMATRIC VIEW
FRONT VIEW
SIDE VIEW
TOP VIEW
command tree
CONCLUSION
OVERALL , WE HAVE SEEN HOW TO MAKE 3D MODEL OF DRILL HANDEL FOR PLASTIC PRODUCT. WE HAVE MADE CLASS A,B AND C SURFACE USING SURFACE COMMANDS IN CATIA V5 , CREATED TOOLING AXIS AND DRAFT ANALYSIS. FURTHEMORE, RIBS AND SCREW BOSSES HAVE BEEN ADDED WHICH FOLLOW PLASTIC FEATURE RULE AND WROTE CALCULATION. LAST BUT NOT THE LEAST THERE IS SEVERAL SURFACE WHICH DO NOT FOLLOW DRAFT ANGLE RULE, SO WE REQUIRE TO CHANGE ANGLE OF CLASS A SURFACE.