Final Panel Project Power Point

Panel Project

Nick MogerBradley Michael

Robin Cox

Scope and Objectives• Design

• Optimization

• Practice

• Manufacturing

• Testing

Scope and Objectives

www.tomsplanner.com

Stringer Concepts

• Z-Stringer– Not strong enough

• Witch Hat Stringer– Simple triangular shape

Failure Conditions

• Web bend angle– Stress Cracks

• Area under hat– Most exposed panel

Optimization

• Kept flanges constant– Minimum 1.5x rivet diameter

• Agreed upon 90°web angle– Easy to check

• Adjust height at expense of width– Too high then too wide

Final Design

Flange end to Flange end = 2.3 inFlange end to Flange end = 2.3 in

Height = 0.64 inHeight = 0.64 inWeb Length = 0.9 inWeb Length = 0.9 in

Final Design

• Quantity - 5

• Rivet Spacing – 23/32nds in– 18/32nds in (from the top and bottom)– Shop aid/jig for “perfect” rivets

• Stringer Spacing– bs-s = 0.5 in

– bs-f = 5/32th in

Predicted vs. Reality

• Original dimensions

-Fabrication not possible; stringers too wide

• Didn’t account for possible misalignments

Reasons For Discrepancy• Coding

– Code was not perfect

• Manufacturing– Stringers were not bent to exact measurements

• Plastering– Our biggest problem!

Snap Crackle Pop

Failure Load (lbf) 18,301 19,635 17,731

Percentage Range (%)

22.6 16.9 25.0

Lessons Learned• Scheduling is important

• Measure twice, cut once

• Multiple ways to a solution

• Fear of the Unknown

• Daaaable Check! (Laugh if you get it)

Conclusion

Snap Crackle Pop

Percentage Range (%)

16.8 10.7 19.4

• Design Successful!

Questions?