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.





