Week 9 - Project - Master Section Development
DEVELOPING - B PILLAR FROM MASTER SECTION
OBJECTIVE: The main objective of this challenge is to create a pillar body by following the master section given in the challenge . we have to create b side features such as dog house and ribs and locators and to finally perform draft analysis on the given component as well as final component and to prepare a report by adding all the possible images.
DRAFT ANALYSIS
Draft analysis is a analysis which is performed on the objects or bodies in order to check the draft angle of various faces in a particular direction which is tooling direction.
Every part like sheet metal parts which are generated from a Press Tool or some forming tools, may be the plastic parts which generally come out from the plastic moulds and maybe the casting parts, all such kind of parts required some drafted face on the surfaces which are parallel to the tooling direction. If we don't provide drafts on the surface then it will stick to the mould surface and whenever the mould is in motion they will destroy the surfaces or also reduced the finishing of surfaces.
The Tooling Direction is basically the direction that the mold pulls apart. The mold is built in two separate pieces, basically. You have a Cavity side and you have the Core side. The Core pulls apart from the Cavity and that's the Dyeline or the Tooling Direction.
And the axis which represents the tooling direction is called tooling axis and selection of this is axis is a crucial step while performing the draft analysis.
CLASS A SURFACE:
In automotive sector, a class A surface is any of a set of freeform surfaces of high efficiency and quality. Although, strictly, it is nothing more than saying the surfaces have curvature and tangency alignment – to ideal aesthetical reflection quality, many people interpret class A surfaces to have G2 (or even G3) curvature continuity to one another.
Class A surfacing is done using CAD applications. Class A surface modellers are also called "digital sculptors" in the industry. Industrial designers develop their design styling through the A-Surface, the physical surface the end user can feel, touch, see etc.
In general CLASS A surfaces are crated using autodesk alias software.
CLASS B SURFACE: Class B surfaces are the secondary surfaces that you can see sometimes, but are less important, such as the inside of your glovebox, ash tray, etc.. These must be smooth and "error-free" as well, but are not held to the standards that class A surfaces are.
CLASS C SUFACE: The Class C finish allows more imperfections than Class A or B. Class C is often specified for interior surfaces not readily visible, surfaces that will be covered by another part when assembled, or surfaces which the Customer feels do not need to meet a high cosmetic finish.
MASTER SECTION: master sections are the guides for design requirements which decides the component structure, shape, size.
CHECK FOR CLASS A SURFACE QUALITY
We can check the quality of CLASS A surface by using boundary and by dissassembling the surface.
1.CHECK WITH BOUNDARY:
Try to create a boundary by using boundary command and check whether its creating single boundary or not
Here we can see that its is creating only single boundary and we can say that the class A surface is good enough to proceed.
2.CHECK WITH DISSASSEMBLE COMMAND:
Now click on dissasssemble command and click on the surface,
We can see that it has only one domain, So we can say that the class A surface is good.
DESIGN OF TOOLING AXIS
1.Extract all the four edges of the master sections.
2. Now create a point in the middle by using between option in point command
3. Create bisecting lines by using line command in surface workbench
4. Now bisect the two bisecting lines and create a main tooling axis
5. To manufacture dog house we need to have a side core tooling axis, for that create a point on the dog house and create line and name it as a side core tooling axis
CREATION OF FLANGES ON CLASS A SURFACE
1. Multiple extract the adjacent surfaces of flange by using multiple extract command and create a boundary for the extracts.
2. Extract the flange lines from the master section given in the challenge
3. Now by using end points of the line create a single by using line command.
4. Now by using the line and the extrats we have try to sweep the surface
5. Repeat the same procedure for the other flange also
6. Now trim the flanges with class A surface
6. Apply edge fillet to the flange and make sure a proper radius is given to the flange
DRAFT ANALYSIS ON CLASS A SURFACE
1.First we will look into the given class A surface,
2. Then go to insert>>analysis>>feature draft analysis.
3.Now align the compass to the tooling axis which we have created and click on any point on the CLASS A surface and observe the colour codes
CASE STUDY 1: Here we can observe that some surfaces are not clearing the draft analysis that is due to patchy and improper class A surface. So we have to give a feedback on this to class A surface design engineers and ask them to modify the surface.
CREATION OF CLASS B SURFACE
To create class B surface simply offset the class A surface without flanges to the thickness of the component. Measure the thickness of the surface from master section.
CREATION OF CLASS B FLANGS:
1. Offset the class A flanges to the required distance
2. Trim it with class B surface.
3. Apply edge fillet to the trims and name it as class B surface with flanges
CREATION OF CLASS C SURFACE
1. First extract the boundaries of class A surfaces into small small divisions.
2. Apply sweeps to the boundaries
3. To the surfaces which are not forming with sweep command use multi section surface and create a proper class C surface and make sure that the class C surfaces are joined together proprly.
FINAL TRIMS:
1. Trim class C surface with class A surface
2. Trim the above trim with the class B surface
3. Craete a solid body by using close surface command in the part workbench
DRAFT ANALYSIS ON SOLID BODY
In a manner similar to that of a class A surface apply draft analysis here also but in the place of selecting class A surface select the solid body
CASE STUDY 2: Here also we can see that some patches are getting created on the C surface. Since they are in red colour we can say that they have a minimum positive draft, so that they can be ejected easily from the moulds. The pathces on the class A surface are due to the irregular class A surface and we don't have any access to change the surface.
DESIGN OF B SIDE FEATURES
CREATION OF DOG HOUSE:
1. Now extract the edges from the master section of the dog house
2. Create a line by using the two points and join them
3. Extrude the joined lines in the respective direction.
4. By using another master section try to extract the limits for dog house
5. Extrude the two extracts.
6. Extrapolate all the edges
7. Trim the surfaces so that we can get the required surface
8. Now by using thick surface command in the solid or art workbench give it the thickness in required directionand split it with the front surface and apply edge fillet and split it with class A surface also.
9. According to the dog house rules we have to cut the dog house for that use master section and cut the dog house and apply edge fillets after giving a proper draft to all the surfaces
CREATION OF LOCATOR:
1. For creation of locators create a plane with reference to the ZX plane.
2. Create a sketch for the 4 way locators and make sure the sketch is constrained properly
3. Pad it and aly draft ato it.
4. Aply entry chamfers as well edge fillets to it.
5. Now finally add or assemble it the dog house body
Let us perform draft analysis on the dog house assembly and see the colour codes
BY USING SIDE CORE AXIS
BY USING MAIN TOOLING AXIS
Now translate this asssembly to the other side, the procedure for this is explained in the below steps.
1. create a mid point by using master section
2. Now create a lane by using this as a reference point
3. Then translate the body other side and make sure the faces are touching the surface and union trim it with the main surface
CREATION OF RIBS
1. By using same plane and point that are used for locators create apositioned sketch for rib also and make sure the sketch is constrained properly or not.
2. Now extract them one by one and hide the sketch now in surface workbench extrude the line in respective direction
3. Now by using thick surface command in part workbench give required thickness to the extrude what we have
4. Extract the surrounding faces and offset that to the required distance and make a split with the surface
5. Apply draft and translate it to the other sides and make sure that a minimum gap of 50 milli meters have to be followed between the ribs and repeat the same procedure on the other sides also.
6. Finally union trim it with the main body and apply edge fillets to them and the views of the final body are given below,
ISOMETRIC VIEW
FRONT VIEW
SIDE VIEW
TOP VIEW
GENERAL VIEW
DRAFT ANALYSIS ON RIBS:
As similar to the previous draft analysis we will perform draft analysis for ribs also and we will observe the colour codes,
CONCLUSSION
Hence we are comcluding that we have designed a pillar body by using the master section and performed draft analysis om each component and we are satisfied with the results. A report has been prepared by attaching all required images and the catia part is attached to the challenge successfully.