Week 9 - Project - Master Section Development
AIM:
To Create the B- pillar component with attachment features and add thickness to it by using Catia V5.
OBJECTIVE:
- Create tooling axis and follow design rules.
- Follow the Master section to create flange
- Follow the master section for thickness and to create the closed volume.
- Follow master section to create Attachment features
- Performing the draft analysis to the component
INTRODUCTION:
The B Pillar is the centre pillar of the car. This pillar actually a sheet metal part which is welded with in the BIW part of car. The B Pillar trim is the attachment to the B Pillar and it improves the aesthetics of car. Most of the trim are manufactured by injection moulding process. The design of B pillar is done carefully to manufactural and usable to the car interior. While manufacturing the part using injection moulding, defects can occur on the plastic part which will destroy the aesthetic look of the car. The design has carefully create the B pillar to the overcome all those defects.
METHODOLGY:
- Creating the Tooling Axis
The tooling direction is used to find the direction in which the part is removed from the core and cavity. The draft angle should be positive to the tooling axis to manufacture the component easily. The step by step procedure of creating the tooling axis is given below.
Step: 1
Creating the point on surfaces respectively also the axis system to the point by extracting the line from master section, mid-point is created between them as shown below.
Step: 2
Now creating the bisecting lines for the intersection lines to the tooling axis. Once we get the bisecting lines for both axis now bisect that both bisecting lines to get min tooling axis.
Step: 3
Finally we get our main tooling axis for the door arm rest component.
- Creating the B surface.
Step: 1
Creating the B-SURFACE by extracting the class A surface, by each surfaces separately, it is offset to certain distance, making point on the master section to get the intersection as shown below.
Step: 2
The extracting the side walls to create the flange on it, and it is extrapolated curve. Using that curve making the sweep using surface as references for 103.8 degree angle as shown below.
Step: 3
Trimming the flange to side walls to the main surface to get exact component as class A surface. And edges are again fillet to get aesthetic component.
Finally we achieved the B class surface by extracting in the Class A surfaces.
- Creation of C Surfaces:
Step: 1
Extracting the boundary of Class A surface and it is make into smooth curves to sweep the curves by using support surface to the 90 degree respectively.
Step: 2
The sweep surface are not properly created at the edges of bin walls, so it is re-created by using multi section surface. It is created by splitting the surface for making two surfaces connect each other.
The boundary at flange walls are bit twisted area so it separated by boundary curve it multi sectioned and it is joined together to make single surface.
Once the all surface joined together it extrapolated to certain distance to trim with Class surface to C surface. Finally we created Class C surface.
Making the Final plastic Component:
To make the final component the Class C surface is trimmed with Class B surface, the output will get the component with 2.5 mm thickness of surface and it is converted into solid body using insert body option in part design as shown below.
- Performing Draft Analysis:
The Draft Analysis command enables you to detect if the part you drafted will be easily removed. This type of analysis is performed based on colour ranges identifying zones on the analysed component where the deviation from the draft direction at any point, corresponds to specified values. This rule of thumb applies to parts with mold depths of up to 2 inches. At this size, draft as low as 1½ degrees will allow for an easy, non-damaging release from the mold when the expected shrinkage of the thermoplastic material occurs.
It’s also important to remember that draft angles are just one component of an effectively designed injection molded piece. Design for manufacture is one of the easiest ways to improve the quality and efficiency of your injection molding process, and it never hurts to stay up to speed on all injection molding best practices.
- Draft Analysis for Class A surface:
Step: 1
Initially we perform the draft analysis to the class a surface to ensure that we have good quality of surface to make Class B and C surface to achieve the same kind of quality surface. First we have to set the compass on the main tooling axis to get the direction of core and part moves along as shown below.
Step: 2
Once compass is locked in the axis, directly click on the surface it will appear quality of draft surface whether, it is pass or failed. Here the draft angle is given as 3 degree. Hence we achieved green colour on top surface. Hence it accepts the draft angle for the surface, so we build good quality component.
Step: 3
Now we check colour variant scale to ensure the maximum and minimum area draft angle is achieved by displaying by green, red and blue colour respectively. If the surface appears red in colour while analysing it is not accepted.
We can check the angle of draft given to surface by using draft tool analysis just point the over the surface where we have check angle of given draft to the component as shown below.
- Draft Analysis for Soild Component:
Step: 1
First we have to set the compass on the main tooling axis to get the direction of core and part moves along as shown below.
Step: 2
Once compass is locked in the axis, directly click on the surface it will appear quality of draft surface whether, it is pass or failed. Here the draft angle is given as 3 degree. Hence we achieved green colour on top surface. Hence it accepts the draft angle for the surface, so we build good quality component. Now we check colour variant scale to ensure the maximum and minimum area draft angle is achieved by displaying by green, red and blue colour respectively. If the surface appears red in colour while analysing it is not accepted.
Step 3:
We can check the angle of draft given to surface by using draft tool analysis just point the over the surface where we have check angle of given draft to the component as shown below.
- Creation of Attachment Feature to the B- Pillar:
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 mould cavity. Dog house and other engineering components are built on B-surface.
Step: 1
Creating the sketch by extracting the class A surface, by each surfaces separately, point and axis system created simultaneously on the surface. Using positioned sketch making as shown below.
Step: 2
The extruded surface is extrapolated, the extract surface from Class A has been offset to make side wall surface of dog house by trimming it.
Step: 3
The sweep surface is converted into solid by thickening the surface for 2mm and it is extrapolated and to make close body it is split into equal distance has shown below.
- Creating the Four way Locator:
Step: 1
Creating the 4 way locator solid feature on dog house, by each surfaces separately, thickened about 2 mm using insert body option in part design as shown below.
Step: 2
Once we extrude the locator’s it has been drafted for angle 0.5 making edges chamfered for 3mm – 45 deg and filleted the edges for radius 0.3 mm as shown below.
Step: 4
The undercut has been made by extrapolated surface and it is offset to the minimal value and it is trimmed to get perfect under cut.
To get the proper clearance for removal of the component is drafted for 0.5 at the undercut area and it is filleted for 0.5 mm as shown below.
Step: 5
It is assembled to dog house body and it is filleted for radius 0.25 of smooth edges as shown below.
- Creating the Rib Formation:
Ribs are a feature in plastic injection molded parts. They are thin extensions that run perpendicular from a wall or plane. They are commonly used to provide additional support and strength to a part.
Step: 1
Creating the sketch by extracting the class A surface, by each surfaces separately, point and axis system created simultaneously on the surface. Using positioned sketch. The sketch extruded to surface and it is thickened for 1mm thickness as shown below.
Step: 2
To make perfect rib positioning on the B pillar surface, it extracted and splitted to requirement as shown below.
Step: 3
The thickened rib is drafted for 0.5 deg and it is assembled to main body by union trim and it is filleted for radius 0.25 of smooth edges as shown below.
Step: 4
In order to check draft analysis to check at Dog house, we create the slider axis, by extracting the surface to required direction. The extracted surface is from the sliding angle from the door arm rest. Creating the point on the center of the surface to create the tooling axis to the Y direction as shown below.
Step: 5
Once we get the sliding tooling axis, usually we gone set the compass on the axis. Hence it accepts the draft angle for the surface, so we build good quality component because it appears the green colour.
Step: 6
Now we check colour variant scale to ensure the maximum and minimum area draft angle is achieved by displaying by green, red and blue colour respectively. If the surface appears red in colour while analysing it is not accepted.
Step: 7
We can check the angle of draft given to surface by using draft tool analysis just point the over the surface where we have check angle of given draft to the component as shown below.
Final Draft analysis on B pillar with attachment features:
Step: 1
First we have to set the compass on the main tooling axis to get the direction of core and part moves along as shown below.
Step: 2
Once compass is locked in the axis, directly click on the surface it will appear quality of draft surface whether, it is pass or failed. Here the draft angle is given as 0.5 degree. Hence we achieved green colour on top surface. Hence it accepts the draft angle for the surface, so we build good quality component.
Step: 3
Now we check colour variant scale to ensure the maximum and minimum area draft angle is achieved by displaying by green, red and blue colour respectively. If the surface appears red in colour while analysing it is not accepted.
Step: 4
We can check the angle of draft given to surface by using draft tool analysis just point the over the surface where we have check angle of given draft to the component as shown below.
Screenshot view of B Pillar with DRAFT analysis:
Front View:
Top View:
Isometric View:
Publication:
Conclusion:
Creation of the B-pillar with attachment features has been successful done for the thickness of 2.5 mm, it has been converted from surface into solid body. The tooling axis has been created according the OEM standard. Drafting Analysis has been performed and results has been updated in step by step methodology. Hence we created perfect attachment of dog house, locators and rib for manufacturing of B-pillar.