Week 9 - Attachment Feature Creation - Challenge 2

SCREW BOSS AND DOG HOUSE DESIGN ON COIN HOLDER

AIM- Create the screw boss and dog house for the centre console coin holder considering the design rules mentioned in the video

GENERAL RULES FOR SCREW BOSSES

• Draft of 0.5 degree on walls of boss
• Thickness is 40% of the nominal wall at the base
• Height to diameter ration- 3:1
• Fillet radius of max 0.25

C is where the doghouse contacts the back side 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

Heght of B should be between 3-6 mm

DOG HOUSE DESIGN-

Extract the base of Class A surface and offset it will part thickness as 2.5mm

 

Draw sketch of rectangle and should be open from oneside for dog house.

Using sweep with tooling direction and draft it at an angle of 1.5 degree for outer surface

Close the upper surface face by offseting the below extracted surface and then after trimmed it

Convert the dog house surface in thickened surface by appling part thicknes as 2 mm

Now for the inside faces of dog house we need side core tooling axis created it in Z direction

Give draft to the inside surface of 0.5 degree

 

Now to create the C and B section as shown in the design rules,offset the base surface in between 3 to 6mm

Extrapolate the surface to achieve desired length

Swith to part workbench and split the C abd b section with thicken part

Again provide draft to the inside surface as show

Give radius/fillet to inside as 0.4*T = 0.4*2.5 =1mm and for outer edges give fillet as inside radius + part thickness

 

And minimum fillet of 0.5 mm

 

Assemble with coin holder main body

 

DRAFT ANALYIS OF DOG HOUSE

 

 

SCREW BOSS DESIGN

Screw boss can be on B surface or it can be on dog house in this we are mounting it on dog house.

Draw circular sketch inside circle of dia 5mm and for outer circle wall should be 0.6*T on one side so outside dia =2*(0.6*2.5)+5(inside dia)=8mm

Pad it with main tooling direction considering height to dia ratio of 3:1

 

H=B*3=5*3=15mm

Give draft of 0.5 degree with tooling axis

Now to support the screw boss we need to give ribs for it

 

 

Draft to ribs of 0.5 degree.

 

Do union trim with screw boss.

 

Assemble to coin holder main body.

 

Screw boss draft analysis

 

Final body analysis

 

design tree structure.