Week 9 - Attachment Feature Creation - Challenge 2

AIM

To Create the boss and Dog House for the Centre console coin holder considering the design rules.

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 ).

• The height of ( B ) should be between 3.0 – 6.0 mm.

The steps involved in the creation of the Screw boss.

• Boss Design
  Bosses are used to facilitate the registration of mating parts, for attaching fasteners such as screws, or for accepting threaded inserts.
  Wall thickness for bosses should be less than 60 percent of the nominal wall to minimize sinking.
  However, if the boss is not in a visible area, then the wall thickness can be increased to allow for
  increased stresses imposed by self-tapping screws. The diameter of the hole in the boss should be equal to0.7 X diameter of the screw.
  
  The boss radius should be a minimum of 0.25 X Thickness.
• Bosses can be strengthened by incorporating gussets at the base or by using connecting ribs attaching to nearby walls.

The base of the coin holder is extracted and the sketch is made for the screw size of M6 considering the design rules.

The sketch of the screw boss hole is then padded and assembled with the main component. Furthermore, fillets and draft angles are applied to the screw boss.

Sketches for the ribs around the screw boss are created. These ribs will provide more strength to the screw boss.

The ribs are then padded with a thickness of 1mm and the draft angle is applied to all the faces along the tooling direction.

The ribs are joined with the screw boss with the unrequired faces removed and assembled with the main component. Fillets are also applied to the edges.

The screw boss is translated from one ened to the another.

The steps for creation of dog house.

Create a point on the position of the screw boss and extract the base surface.

A sketch is created for the dog house.

The sketch is then swept along the draft direction with a draft angle of 1.5deg.

The top surface is closed and the surface is thickened to form a solid.

Side tooling axis is created to clear the draft for inside faces of the dog house.

The intersection between the component and the doghouse is to considered.

The suface is trimmed in order to satisfy the above condition of intersection then this surface is split from the body to form the final shape of the dog house.

The above image shows the final dog house.

Draft Analyis of the Dog House.

First the draft analysis of the dog house is donw with respect to the main tooling axis with an draft angle of 1.5deg.

Isometric view

Front view

Top view

Bottom view.

Draft analysis along the side tooling axis.

Bottom view.

tHE above image shows the draft analysis of the component along the main tooling axis.

Front view.

Right side view.

Top view