Door Arm Rest Week 8 Challenge

AIM: To generate the draft analysis of the arm rest model.

OBJECTIVE:

To create the Door Arm Rest Class-A surface to final solid model and at the end performing the draft analysis on the model.

THEORY:

Draft analysis helps to detect if your drafted part is easily removable from the mold (in case of plastic component) or die (in case of sheet metal). All plastic components will have a minimum draft of 0.5 to 3deg. And for automotive sheet metal parts the draft will be 7deg or more. If a mold wall is perpendicular to the part ejection, there is ample friction or interference between the mold and the part which will not allow one to release from the other. This is why design engineers give a minimum draft to the part.

In CATIA V5 the feature draft analysis dialog box look like this:

Mode:

• The mode option let you to choose between quick analysis and full analysis mode.
• In quick mode there are 3 ranges with blue, red and green colors. In case of plastic component we will set the draft angle as 3deg.

Display:

• The first box is to open and close the color scale dialogue box.
• The second box is the analysis under running point, when activating the checkbox and move the pointer over the surface. This option enables you to perform a local analysis. Arrows are displayed under the pointer, identifying the normal to the surface at the pointer location (green arrow), the draft direction (red arrow), and the tangent (blue arrow). As you move the pointer over the surface, the display is dynamically updated. Furthermore, circles are displayed indicating the plane tangent to the surface at this point. The displayed value indicates the angle between the draft direction and the tangent to the surface at the current point.
• Click the No Highlight Representations button to set the display option of highlight effect sources as "on/off". When checked "On" the surfaces are selected but they will not be seen in the specification tree.
• Click the Light Effect button and the colors of the analyzed elements react to the light source

Direction:

• The first check box is locked direction icon which is used to lock the direction of the compass after selecting the specified direction.
• Click on compass icon to specify the new pulling direction to remove the part.
• Click the Inverse button to automatically reverse the draft direction. When several elements are selected for analysis, the draft direction is inverted for each element when the button is clicked.

Tooling Direction:

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. There are different methods to find out the tooling direction. Here we are using bisecting method to find out tooling direction. We can use any method the ultimate aim is to reduce the cost of manufacturing by reducing the complicity in manufacturing the component.

PROCEDURE:

CREATE TOOLING AXIS:

• Create a point in the middle of the hole. And insert the system axis.
• Create intersection on the XY plane.and draw a line on the two walls and create bisecting line using with two lines
• And create another intersection on the YZ plane cut in half section and create an intersection that has only one wall. Create one line on the wall intersection and draw a random line on the point this line gives angle from the intersection line.
• After creating Tooling Axis with using the above bisecting and random line.
• Create another tooling direction through Y direction.

B SURFACE CREATION:

• Extract the arm rest top surfaces.and un trim and do extrapolate up to 50mm.
• Create a sketch on the middle of the surfaces for getting two curves between the surfaces.create a line through y direction. and extrude a surface using a guide curve and create a bend between the one of the top surface and middle plane.
• and trim the all surface of the top and offset 2.5 mm
• And extrude walls and untrim it then extrapolate up to 50mm.and trim the surfaces.
• give the edge fillets based on dimensions of the fillets.

CREATION C SURFACE:

• Create boundaries on class A surface step by step based on straight planes and curved planes.
• creates boundaries differently divided by the angle of the boundary.
• create sweeps on boundaries
• we will get a small gap between the surfaces .Its cleared using the joining option gap value is maintained 0.3.
• trim the surfaces and join the classA And class b surfaces.than will get c surface.
• Then I will go to part design and fill the surface.

DRAFT ANALYSIS:

• Open the Draft analysis by Insert > Analysis > Feature Draft Analysis..Select the Compass - Direction in Draft Analysis and align it to the Tooling Axis and then lock it
• After locking it a cross symbol will occur at the pointer,select the surface and the surface selected turns into green.
• In the Draft Analysis 2 box,select the green column to change the draft angle to 3 degrees.
• The color should be green in colour.

CONSTRUCTION TREE: