Challenge

17. INTERIOR DOOR TRIM PANEL IN CATIA.

AAjinkya Hatolkar3 Sept 2023

Development of a Door Trim panel

Draft Analysis ?

The Draft Analysis allows the user to easily analyse a part for proper draft angle. A Draft Angle describes the amount of taper for Molded or cast parts perpendicular to the parting line.

Draft angles ?

Draft angles are very important in thermoforming product design. If the product is formed onto a female or negative Mold, it shrinks away from the Mold sidewalls. As a result, true female or negative products can be thermoformed with vertical walls having zero draft angles. If the product is formed onto a male or positive Mold, it shrinks onto the Mold sidewalls. A draft angle of 1–5 degrees is recommended for all male or positive products.

For Plastic components we use 3 degree as a minimum draft angle.

while for automotive sheetmetal component draft angle should be lower than 7 degree.

Tooling Direction for Plastic Part

Tooling direction is main consideration for plastic part and mold parts because it defines movement of mold part and possibility of plastic part to come-out from mold part (Core and Cavity).

Tooling Direction:-

In Molding machine arrangement is given to open the mold along a direction which is known as Tooling Direction.

In other words. The mold is built from two separate halves (Core and Cavity) and tooling direction basically define the direction of mold pulls apart.

Tooling direction is known as primary direction.

WHAT IS CLASS A, B, C SURFACES ?

Class A:- Styling or A class surface are the terms used in plastic product design. That means the surface of a component that is smooth (aesthetic) or visible side to the human eye after the part is assembled.

Class B:- It is an engineering surface, and it gives you thickness from class A surface

Class C:- when Class A and Class B surfaces are joined along the tooling axis it is called class C surface.

WHAT IS DOG HOUSE ?

Dog house is an engineering feature used in plastic trim design. Dog houses are used as supporting feature. Sometimes other engineering features like snaps; locators etc. are mounded on them to increase their strength. Dog houses are subjected to draft analysis to prevent breakage of the component during ejection from Mold cavity. Dog house and other engineering components are built on B-surface.

CONDITION FOR DOG HOUSE

"C" is where the doghouse contacts the backside of the surface

Doghouse wall thickness at the intersection of the part wall ( C ) should be 40% or less than the main wall stock ( T ).
The height of ( B ) should be between 3.0 – 6.0 mm

METHODOLOGY :-

1) ARM REST

AFTER CHECKING FOR ANY GAPS WE HAVE FOUND ONE GAP IN SURFACE.

TO REMOVE IT WE HAVE TRIED JOIN COMMAND AND INCRESED TOLERENCE LIMIT FROM 0.001 TO 0.003 BUT STILL IT DID NOT REMOVE SO WE USE ANOTHER METHOD. WE EXTRACT TWO FACES SEPERARED BY THAT BOUNDRY SHOWN BELOW

WE TRIM THEM WITH EACH OTHER

BUT THERE ALSO A SMALL EDGE REMAINING WE SPLIT THAT BY CREATING A SPLINE ON THAT AREA.

NOW WE HAVE IMPROVED CLASS A SURFACE

TOOLING AXIS

TO CREATE IT WE HAVE EXTRACTED BASE SURFACE THEN CREATED A POINT AT CENTRE AND A LINE IS DRAWN PERPENDICULAR TO IT.

CLASS B SURFACE

TO CREATE CLASS B WE FIRST OFFSET ARM REST WITH THE HELP OF MASTER SECTION AT DISTABCE OF 2.5MM

BY USING BOUNDRY, SPLINE, MULTISECTION SURFACE MULTIPLE TIMES AT DIFFERENT LOCATIONS WE GET CLASS B SURFACE WHICH IS AS BELOW.

CLASS C SURFACE

A+C

(A+C)-B

CLOSED BODY CREATION

ENGINEERING FEATURES :-

FLANGE :- Flanges were created on the arm rest with the reference dimensions from the master sketch provided. The purpose of the flange was to provide slots for the heat stakes and locator which are required to assemble the two components together and constraint the motion between them.

SAME PROCESS IS FOLLOWED FOR OTHER FLANGES

DRAFT ANALYSIS

1. First Draft Analysis is created on Class A surface.

2. Second on Closed Body.

3. Third draft analysis is performed on complete solid body.

DRAFT ANALYSIS IS DONE ON FINAL BODY FOR NOW IGNORE THE FLANGES BECAUSE IT IS WILL HAVE DIFFERENT DIFFERENT TOOLING AXIS.
DRAFT ANALYSIS IS DONE ON THE SOLID BODY HERE IT IS SHOWING GREEN COLOR WHICH MEANS THE DRAFT ANGLE IS 3 OR MORE THAN 3 DEGREE.
THE BLUE COLOR MEANS THE DRAFT ANGLE IS NEGATIVE DEGEE WHICH IS MANDATORY FOR THE SOLID BODY BASE SIDE.
THERE ARE SOME RED PORTION WHICH IS ON A SURFACE THE A WHICH WILL COME AT SOME PORTION.
RED LINES ARE OF FILLETS WHICH IS ACCEPTABLE.
WHEN THE DRAFT ANGLE IS 2.9 SOME OF THE ARE GETS GREEN WHICH IS ACCEPTABLE.BUT WITH 2.7 THERE IS NO RED COLOR
THE RED COLOR IS COMING BECAUSE IT IS VERTICAL PORTION.

SO WE CREATE ANOTHER SIDE TOOLING AXIS, TO PERFORM HORIZONTAL DRAFT ANLYSIS.

Feature Tree For Arm Rest

2. BOTTLE HOLDER

EVERYTHING LOOKS GOOD HERE SURFACE IS OK SO WE MOVE FURTHER IN CREATION OF CLASS B SURFACE

CREATION OF TOOLING AXIS

CLASS B SURFACE

WE OBTAINED CLASS B SURFACE BY DIRCTLY OFFSETTING 2.5 CLASS A SURFACE. ALSO AFTER LOOKING IT EVERYTHING LOOKS OK SO MOVE AHEAD IN CREATION OF CLASS C SURFACE

CLASS C SURFACE

TO CREATE CLASS C SURFACE WE CREATE BOUNDRY OF CLASS A SURFACE AND SWEEP IT. WE GET CLASS C SURFACE DIRECTLY

CREATION OF CLOSED BODY

FOR FINAL TRIM WE FIRST JOIN CLASS A & CLASS C THEM TRIM IT WITH CLASS B

ENGINEERING FEATURES :-

FLANGES

FINALL SOLID BODY AXIS IS CREATED ON THE HOLE BECAUSE SO THAT IT WILL HELP TO TRANSFER THE HEAT STAKE ON THE EXACT LOCATION.

DRAFT ANALYSIS

1. DRAFT ANALYSIS ON CLASS A

THE FIRST DRAFT ANALYS IS IS DONE ONT THE CLASS A SURFACE TO SEE WETHER THE TOOKING AXIS IS CORRECT OFR NOT HERE IT IS SHOWING GREEN COLOR WHICH MEANS THE

DRAFT ANGLE IS 3 OR MORE THAN 3 DEGREE. THIS MEANS THE TOOLING AXIS IS CORRECT.

THERE IS RED COLOUR WHICH WILL BE THERE BECAUSE THAT IS THE HORIZONTAL SURFACE.

2. DRAFT ANALYSIS ON CLOSED BODY

Feature Tree For Bottle Holder

3. MAP POCKET

CLASS A SUFACE

EVERYTHING LOOKS OK SO WE MOVE TO NEXT STAGE WE CREATE TOOLING AXIS AND PREPARE FOR CLASS B CREATION

FOR CLASS A SURFACE CHECKING WHICH IS THE BEST DIRECTION FROM WHERE ONE CAN SEE MAXIMUM EDGES FROM THE NORMAL VIEW .

THEN EXTRACT THAT SURFACE CREATE A POINT AND CREATE A LINE FREM THAT.

CLASS B SURFACE

CLASS C SURFACE

CREATION OF CLOSED SURFACE

ENGINEERING FEATURES :-

FLANGES

FOR CREATING FLANGE FIRST EXTRACT THE MASTER SECTION THEN EXTRACT THE EDGE THEN USED SWIPT COMMAND AFTER OFSET THE SURFACESS TO CREATE PART OF IT THEN TRIM AND THEN USED CLOSE BODY COMMAND AND LASTLY ASSEMBLE THEM WITH MAIN BODY

DRAFT ANALYSIS

1. DRAFT ANALYSIS ON CLASS A

2. DRAFT ANALYSIS ON CLOSED BODY

3. DRAFT ANALYSIS ON FINAL PART

DRAFT ANALYSIS IS DONE ON FINAL BODY FOR NOW IGNORE THE FLANGES BECAUSE IT IS WILL HAVE DIFFERENT DIFFERENT TOOLING AXIS.
DRAFT ANALYSIS IS DONE ON THE SOLID BODY HERE IT IS SHOWING GREEN COLOR WHICH MEANS THE DRAFT ANGLE IS 3 OR MORE THAN 3 DEGREE.
THE BLUE COLOR MEANS THE DRAFT ANGLE IS NEGATIVE DEGEE WHICH IS MANDATORY FOR THE SOLID BODY BASE SIDE.
THERE ARE SOME RED PORTION WHICH IS ON A SURFACE THE A WHICH WILL COME AT SOME PORTION.
RED LINES ARE OF FILLETS WHICH IS ACCEPTABLE.
WHEN THE DRAFT ANGLE IS 2.9 SOME OF THE ARE GETS GREEN WHICH IS ACCEPTABLE.BUT WITH 2.7 THERE IS NORED COLOR
THE RED COLOR IS COMING BECAUSE IT IS VERTICAL PORTION.

SECON TIME TOOK 0.45 DEGREE FOR THE HEAT STAKE AND FOR THE LOCATER.

FEATURE TREE FOR MAP POCKET

4. LOWER SUBSTRATE

CLASS A SURFACE

AFTER LOOKING CLOSELY THERE ARE NO ISSUES IN CLASS A SO WE MOVE TO NEXT STEP CREATION OF TOOLING AXIS

FOR CLASS A SURFACE CHECKING WHICH IS THE BEST DIRECTION FROM WHERE ONE CAN SEE MAXIMUM EDGES FROM THE NORMAL VIEW .

THEN EXTRACT THAT SURFACE CREATE A POINT AND CREATE A LINE FREM THAT.

CLASS B SURFACE

AFTER OFFSETTING FOR 2.5MM CLASS A AND REWORKING ON IT WE GET CLASS B SURFACE

CLASS C SURFACE

CREATION OF CLOSED BODY

WE FOLLOWED SAME STEPS AS PREVIOUS ONE

FIRST JOINED SUFACES A+C

AND THEN TRIMMED IT WITH CLASS B SURFACE

CREATION OF ENGINEERING FEATURES

1. DOG HOUSE

2.HEAT STAKES

DRAFT ANALYSIS

1. DRAFT ANALYSIS ON CLASS A

2. DRAFT ANALYSIS ON FINAL TRIM

3. DRAFT ANALYSIS ON CLODED SURFACE

4. DRAFT ANALYSIS ON FINAL BODY

DRAFT ANALYSIS IS DONE ON FINAL BODY FOR NOW IGNORE THE FLANGES BECAUSE IT IS WILL HAVE DIFFERENT DIFFERENT TOOLING AXIS.
DRAFT ANALYSIS IS DONE ON THE SOLID BODY HERE IT IS SHOWING GREEN COLOR WHICH MEANS THE DRAFT ANGLE IS 3 OR MORE THAN 3 DEGREE.
THE BLUE COLOR MEANS THE DRAFT ANGLE IS NEGATIVE DEGEE WHICH IS MANDATORY FOR THE SOLID BODY BASE SIDE.
THERE ARE SOME RED PORTION WHICH IS ON A SURFACE THE A WHICH WILL COME AT SOME PORTION.
RED LINES ARE OF FILLETS WHICH IS ACCEPTABLE.
WHEN THE DRAFT ANGLE IS 2.9 SOME OF THE ARE GETS GREEN WHICH IS ACCEPTABLE.BUT WITH 2.7 THERE IS NORED COLOR
THE RED COLOR IS COMING BECAUSE IT IS VERTICAL PORTION.

SECON TIME TOOK 0.45 DEGREE FOR THE HEAT STAKE AND FOR THE LOCATER.

SOME PORTION OF THE DOG HOUSE AND HEAT STAKE ARE LOOKING BLUE BUT IT IS OK BECAUSE WHEN WE WILL REVERSE THE DIRECTION IT WILL TURN RED.

HOW DID I PLACE THE HEAT STAKE EXACTLY ?

IN ASSEMPLY SECTION I USED AXIS TO AXIS TRANSFER OPRATION AND TRANSFER IT TO THE AXIS CREATED WIN THE INDIVIDUALL FILES.

FEATURE TREE FOR LOWER SUBSTRATE