Week 9 - Attachment Feature Creation (Ribs & Screw Boss) - Challenge 1

Aim : to create Ribs & Screw boss for Door handle.

• Given Class A surface is analysed for irregularities.

• Draft analysis of A surface

• Creation of B surface : B surface is created by offsetting the A surface inwards. irregularities are eliminated. by extracting and Extrapolating the surfaces and trimming them together.

• Creation of C surface : C surface is created by sweep command. sweep is done with reference to the Surface.

• Final Trims : individual B & C surfaces are trimmed together. then both surfaces are trimmed with A surface.

• Surface model is converted into Solid

• Rib Creation :- Ribs are thin protrusion that extrude perpendicular to the wall or plane. it provides economical stiffness and strength without increasing over all thickness of the part.

Calculations for rib :-

1. Rib thickness = 0.4* t = 0.4*2.5= 1 mm
2. Rib Height = 5 * t = 5*2.5 = 12.5mm
3. Draft angle = 0.5 degree
4. Fillet radius = 0.25 mm

we will extract base surface, create sketch on it and Extrude the ribs along tooling direction. After thickening we will provide draft of 0.5 degree & give fillet of 0.25 mm radius to all faces. then trim the rib with main body.

• Intersection of Ribs

• Creation of Screw Boss : for Creating screw boss we will create a sketch of two circle & pad it with the reference of tooling axis. then the part is trimmed with main body.

Calculation for screw boss

1. Inner Circle Dia = 5.2mm
2. Outer circle Dia = 5.2+(2*w) (where w= 0.6*t) = 5.2+3=8.2mm
3. Draft angle = 0.5 degree
4. Fillet Radius = 0.25 mm

• Draft Analysis of Solid part