Week 9 - Attachment Feature Creation - Challenge 2

SCREW BOSS & DOG HOUSE CREATION:

SCREW BOSS:

• They are used to aid in the assembly of molded parts by providing a channel for a screw.

Giudelines for screw bosses:

1. Width (W) = 0.6*t
2. Fillet radius = 0.25mm (max)
3. Draft angle = 0.5 degree
4. Ratio of Hieght to Diameter = 3:1 respectively

DOG HOUSE:

• Dog house is an engineering feature used in plastic trim design. Dog houses are used as supporting feature. Sometimes other engineering features like snaps; locators etc. are mounded on them to increase their strength.

Guidelines for Dog house:

1. Min. Height of dog house = 6mm
2. joining portion width (C) sould be less than 40%of main wall thickness(T).
3. Joining portion Height (B) = 3-6mm
4. Ratio of width to Height =3:1
5. Min. width (X) = 12mm
6. Min.draft angle =1.5 degree

TOOLING AXIS CREATION:

• check the possible direction of tooling axis.
• Here the side walls are perpenticular to the base surface, so creating bisecting method to create tooling axis insteadwe can create normal line to the base surface.

SIDE CORE TOOLING AXIS:

DRAFT ANALYSIS:

• Do draft analysis for the given solid component

SCREW BOSS:

• Sketch the circle for create the boss, ensure the sketch solving status.
• make Pad the sketch to 6mm (the min. value)
• Again draw a sketch for making supporting ribs to screw boss
• Extrude it with the thickness of 1mm with neutral fiber.
• Apply Draft for that screw boss and ribs with draft angle 0.5degree and create chamfer for rib.
• For multible screw bosses, Translate the main boss by copy it to the another part body.

Translation:

DOG HOUSE:

• The srew boss is need to place over the dog house, but the screw boss in same part body.
• To avoid complecation deactivate the screw boss for a while.
• Create sperate plane for Dog house creation. sketch the outline of dog house.
• Perform Sweep for the sketch instead of pad or extrude it. bcoz in sweep can create drfat angle.
• Thicken the surface with 2mm. and make draft the inside surface and fillet it.
• To create joining portion of dog house to make split the solid with sufare with width = 1mm and Height = 3mm
• Split the surface with dog house.
• Do draft analysis for the Dog house along with both main tooling axis and side core axis.
• Make fillets all edges and assembly together with part body.

Draft analysis with main tooling axis:

Draft analysis with side core axis:

• Now activate the screw boss and translate it over the dog house.

Various view:

Isometric view:

Front View:

Side view:

Top view:

cross sectional view:

END