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

Aim- Create the rib for the Drill Handle considering the design rules.

Tooling axis creation-

Draft analysis-

Ribs creation-

1. Draft: 0.5 deg per side (minimum), but this value should not be high enough that it will cause failure for other consideration. For example, more draft will result in less thickness at the top surface.
2. Thickness of ribs: 40% of wall thickness or 0.4*t where t is the wall thickness.
3. Height: ≤ 5 times the wall thickness i.e. 5*t ..
4. Spacing (for more than 1 rib): 3:1- steel height/width ratio (maximum). h/w=3or2(preferred) where h is the height of the rib and w is the space between two ribs.
5. Minimum thickness at the tip: 0.75
6. Radius: 0.25mm max
7. Ribs on opposite side of the wall should be offset
8. Ribs should be connected to other structural features where possible.
9. Rib root thickness should not be more than 30% of the wall thickness.

Screw Boss creation-

1. Draft: 5 deg on each walls.
2. Wall thickness: 40% of the nominal wall thickness i.e. 0.4*t where t is the wall thickness which is 2.5mm in this case.
3. Height/diameter: 3:1 steel but 2:1 is preferred.
4. Radius of the fillet: minimum 0.25mm.
5. Boss gussets (rib like structure giving strength to the screw boss) must meet ribs guidelines.
6. Avoid merging the screw-boss into wide wall.

Views-

Conclusion- All the objectives have been achieved.