Week 9 - Attachment Feature Creation - Challenge 2

Aim:

Create the boss and Dog House for the Centre console coin holder considering the design rules mentioned in the video.

General Guidelines for Bosses:

• Draft - 0.5 degrees on walls of boss
• Thickness - Typically 40%* of the nominal wall at the base.
• Height to Diameter Ratio - 3:1
• Radii - 0.25mm maximum radii.
  

"C" is where the doghouse contacts the backside of the surface

• Doghouse wall thickness at the intersection of the part wall ( C ) should be 40% or less than the main wall stock ( T ).

• Height of ( B ) should be between 3.0 – 6.0 mm

PROCEDURE :

SCREW BOSS CREATION :

First I created two circles in the sketch.

The inner-circle diameter is 5.2 mm and the outer circle diameter is as per design criteria. The thickness of the Screw boss should not be higher than 40% of the bass.

The thickness of Coin Holder -2.5 mm

The diameter of the outer circle is -7.2mm

As per the given parameters, the draft angle and fillets are provided.

Copied this screw boss and paste it separately then translate it on a suitable coordinate.

And assemble to the main body.

DOG HOUSE CREATION :

First of all, I deactivated the screw boss

Extract the Base of the Class A surface and offset it by 2.5mm and make a point.

Then I created a rectangular sketch (one end made as construction).

Next, I used the sweep command with a draft angle of 1.5 degrees and a height of 12 mm.

To adjust the height and bring it the perfect dog house shape I used the command Surface Untrim, Offset, and Trim.

After that thicken it by 2mm.

• To get the perfect shape we extract the inner plane and offset it by 22.5mm and Split it to the body.

• The draft angle of the inner side of the dog house is 0.5 degrees.

• The edge fillet on the inner side of the dog house is given a nominal diameter of 1mm.

• The height of the dog house is given as 4mm whereas given design parameters it was indicated between 3-6 mm.
• To achieve the C value in the Dog house as mentioned in the question, I have made an extract on the inner face of the dog house and made an offset for 1mm (0.4*2.5mm =1mm).

• After that, we Extrapolate the offset and base offset and trim it in the required side and we get the output as shown in a given image,

• Split it with dog house to get C and B sections.

• Drafted the cut C section by 0.5 Degrees.

This was done to achieve a proper Draft analysis result.

• Fillets – Edge fillets were done on the inner side of the dog house ( Intersection of part wall C ) for a nominal 1 mm.

Draft analysis :

Now, the Dog House need to be checked for the draft analysis to ensure if all the features have passed the tooling direction :

1. Open the feature draft analysis from the insert menu.
2. Move the compass to align with the Side tooling axis and then select the component.

3. Here, change the minimum drafting angle to 1.45 degrees since the draft provided to Dog House is 0.5.

• Draft Analysis along the main Tooling axis :

• Screenshots of the completed design in various orientations (Isometric, Front, Side, and Top View)

Isometric View

Front View

Side View

Top View

RESULTS : Created the boss and Dog House for the Centre console coin holder considering the design rules.