Week 9 - Attachment Feature Creation - Challenge 2

DOG HOUSE DESIGN

INTRODUCTION

Dog house is a feature that helps you to avoid sink marks.

OBJECTIVE

To Create the Door Handle Component from the given Class-A surface.
To Create the tooling axis for the given Class-A Surface meeting the requirements of the draft angle.
To Attach B side Features in the component.
To perform the Draft analysis on the model.
To create the Dog House for the Door trim considering all the design rules.

METHODOLOGY

We get the component and with the help of the design rules for dog house we design the following.
Then after that we do the draft analysis.

TOOLS USED:
Boundary
Join
Multiple extract
Trim
Surface offset
Draft analysis
Intersect
Surface sweep
Close body surface

DESCRIPTION

1. CREATING TOOLING AXIS The Tooling Direction is basically the direction that the mold pulls a part. 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 Dye line or the
Tooling Direction.
Open the given CAT part file.

Check for gaps between surfaces for that click on join and then preview.
If theres any gap between the surfaces join them with a maximum tolerance of 0.003 mm

Extract the boundary and dissemble the boundary.

2. PUBLICATION
Publication is done to the component to make it visible and navigate easily.
To publish the component go to tools > publications and then select the tooling axis and the class A surface.
A separate tree structure is formed under the main part

3. 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 color ranges identifying zones on the analyzed element where the deviation from the draft direction at any point,
corresponds to specified values.
Before going to drat analysis go to customized view parameter >under mesh >check material and then click ok.
Now for draft analyses go to insert » analysis » feature draft analysis.
Use the compasss to define the draft direction.
In the colour scale change the draft angle to 3 degree.
The component changes to green in indication of passing draft angle.
Use running point to check the angle on the component.

The draft analysis is complete.

4. CREATING CLASS B SURFACE

Extract the surfaces from the class A using multiple extract and untrim them.
Use Extrapolate to make sure that all the untrims are properly intersected to trim and offset the surfaces to 2.5 mm to create the thickness.

Trim the extra surfaces using trim command.

Insert them into new geometrical set and name it with respective part names.
Apply fillets to the model after creating the entire surface.
If the edges are outside the fillet value will be added to the thickness of the component and if the edges are inside, the fillet
value will be subtracted from the thickness of the component, for instance the thickness of the component Is 2.5mm the fillet
value is 15mm so the outside portion value should be 17.5mm and inner eges should be filleted 12.5mm to get uniform thickness.
Perform trims one at a time so that it will be clear to understand.

5. CREATING CLASS C SURFACE

Extract the boundary from the class A surface using boundary command.
Using disassemble tool to divide the boundary as the boundary contains domains.
Use sweep command > choose profile type line > subtype as with draft direction > choose guide curve and draft direction > draft
angle as 3 degree > preview.

JOINING CLASS A AND C SURFACES

TRIM A+B & C

CREATING SOLID MODEL BY USING CLOSE SURFACE IN PART DESIGN

6.Dog House Design

Dog house is an engineering feature used in plastic trim design. Dog houses are used as supporting feature. Dog house is a feature that helps you to avoid sink marks.

Rules

Dog house wall thickness and sink saver-
“C” is where doghouse contacts backside of surface.
Dog house wall thickness at intersection of part wall (C) should be 40% or less than main wall stock (T).
Height of (B) should be between 3.0 – 6.0 mm.

Dog house height

Minimum height (H) of dog house is 6mm.
Less than 6mm causes weak steel condition.
3:1 ratio of steel width to height, 2:1 is preferred.

Dog house width

Minimum dog house width (X) for doghouse is 12mm.
3:1 ratio of steel width to height, 2:1 is preferred.

Dog house draft to die draw

Minimum draft (D) for dog houses 1.5 degree to die draw.
If a slide is being considered, this requirement can change to 3 degrees minimum.

Sketch Used For Screw Boss Creation