Door Arm Rest Week 8 Challenge

                                                                                                                     DETAILED REPORT OF  DOOR ARM REST 

In the Door Arm Rest challenge, we are going to see how to create a tooling axis and according to the OEM standard and   according to the axis how we are going to create a model with different commands and features.

TOOLING AXIS

Before we startup a model to sketch, first we have to ensure the tooling axis direction of the part. Which axis looks to clear all the faces and importantly create the axis which will be in low cost without a side core. Side core is one which always be an expensive one.

In this model its clearly come to know that side core will play a major role in this model to clear the ribs crated in the center wall of the part in y direction. We will talk about the side core later, first we confirm the main tooling axis.

In the above figure shown that the possibility of creating a tooling axis in each direction. While we have a hole in the center portion of the part that too in a z direction, the hole can be only cleared through the z direction tooling axis.

CREATION OF A TOOLING AXIS

To create a tooling axis we need mean point of the z axis point to the center of the point. To recreate that we create an intersection through the xz plane and yz plane. Using the intersection create a reference line and do a bisecting method to create axis.

 *Creation of point and axis system

Take the base surface of the wall as a reference to create a point as an option point on surface. Extract the base, untrim them and create a point in the center of the extraction and insert the axis system.

XZ intersection

Take intersection of xz plane with the center point as a reference. Create a reference line and bisect them.

YZ intersection

Here we use positioned sketch method for yz intersection to give an angle value manually because it’s a one side face. Use positioned sketch select yz plane with the projection point as a point on the base surface.

Use the projection element feature to project the line in yz direction, create a reference line along the projected line and create a random line from the center point with no relation and constraint the line by giving the angle as 3degree.

BISECTING LINE

Select the xz and yz line with the center point as reference to create an bisecting line. This line is mentioned as a main tooling axis.

To verify the tooling axis select the line and select normal view and look whether all the faces of the part a visible in the view point.

CLASS B SURFACE

In to the design of the model, first we create a class b surface. The class b surface can be split in to the first half,second half and side fillet portion.

• FIRST HALF

In to the first half of the model , first extract the top surface and untrim trim and make an extrapolate widely to make easy to trim,  for the upcoming process.

 Next take the side flat face to extract and extrapolate up to top surface to trim them.

Before we entering in to the trim we need to ensure whether the created faces are offset to 2.5mm to inner side of the Class A surface.

Apply fillet radius to the corner of the trim surface, radius can be measured in the Class A model.

Has the fillet face looks angled face so it cant give the exact radius value. So we extract the face and make untrim them to measure the radius and apply the radius value with the given thickness (17-2.5=14.5mm). It’s a inner surface we have to decrease the value from the thickness to maintain the thickness value between Class A and Class B.

COMPLETE FIRST HALF

Make the final trimed part as a publication to highlighted separetly in the geometrical set.

SECOND HALF

For the second half of the surface take the lower flat surface, extrude them and make extrapolate up to the top surface. Same as extrude the top face and extrapolate to previous extrapolated element to make a cut by an offset of 2.5mm.

COMPLETE SECOND HALF

SIDE FILLET SURFACE

This one look little bit complicated to create a fillet here. First create a point in the center line of the fillet face to create a axis system for intersection.

Using positioned sketch take yz plane with the projection of the axis system take an intersection of yz plane. Make them as an construction line and create a line with a tangent relation in the center to create a sweep. Constraint the line with the random dimension to make the sketch as iso constraint.

Create a multiple extraction line at the mid line of the fillet face to use as a guide curve to create a sweep. Convert the multiple extraction line into smooth curve so that sweep surface avoids lines on the surface.Offset the sweep surface to a 2.5mm.

Next extract another fillet connects towards this sweep make them untrim offset to 2.5mm.

Then create an adjacent line along the surface and split them to blend the component with the sweep surface. Finally join the all three surface to a single solid fillet face.

TRIM

To create a complete Class B surface, we need to join all the 3 surface, by trim operation.

• First trim the first half with the fillet surface to a single part by create an extrapolate with the fillet face of one side to extend pass the first half element to make a trim.

Next trim this one with the second half of the part to form a single element. Before trim extrapolate the outer boundary surface to intersect with previous trim surface to a single part.

 WALLS

The last part left in a Class B is walls in the center of the model. First extract and untrim the all the faces except the base and offset to 2.5mm and trim them. In the side walls we have seen a two flat faces on one side. Both of them to be untrim and trim the wall and finally join all the surface to single wall.

Then extract the base untrim them then take an offset to extrapolate to intersect with the wall to perform a final trim for the wall.

FINAL CLASS B TRIM

Trim the wall with the top half of the surface to complete a complete Class b and apply the fillet to the required areas.

FILLETED CLASS B

CLASS C SURFACE

To create a Class C surface, create a boundary to the Class A with no propagation and create a sweep. Here we are going to do three different sweep method

• Sweep with draft direction
• Sweep in explicit method with a reference surface.
• Sweep in a line method with a reference surface.

Create a sweep all over the boundary and mention the angle 3 degree for the draft direction method.

Use sweep with draft direction method for flat boundary areas, In some fillet areas use with reference surface of explicit mode and use multibody feature in other areas.

Sweep with draft direction

Sweep with reference (Explicit method)

Sweep with reference surface (Line method)

Here mention angle according to the sweep we need. We had given the angle as 90 degrees.

Multi section surface

FINAL SWEEP BOUNDARY TRIM

Some of the place of the boundary sweep area has some gaps. Extrapolate those boundary edges and trim them to a complete sweep surface and join with Class A surface.

Sweep the center hole by create a boundary and sweep with draft direction of tooling axis. Join the boundary sweep, center hole sweep and Class A to a final Class C surface.

DOOR ARM REST SOLID BODY

Trim the Class C with Class B to get a complete Door Arm Rest part.

Next go to the Part design to form a complete closed solid surface.

FINAL DRAFT ANALYSIS

We now apply the draft analysis to the final created solid surface to check the draft angle between Class and Class B.

So, in the final draft analysis flat faces are almost cleared with the axis. But the drafted face side is in negative side.

GEOMETRICAL CONSTRUCTION

DIFFERENTIAL VIEWS WITH DRAFT ANALYSIS