Sheet Metal
Why are sheet metal repairs “deburred”?
To remove stress risers, and to make sure the rivets buck properly.
The metal on the outside of a bend is under (compressive or tensile) stress?
Tensile Stress
Sheet Metal "Brake" is a tool for __________ metal.
Bending
What is the parameters for edge distance for protruding head rivets and flush rivets?
2D - Protruding head rivets
2 1/2 D - Flush rivets
What is Precipitation Heat Treatment?
Is done the same way as Solution Heat Treatment but is placed back in ovens at a lower temperature, then still-air cooled.
A well-designed rivet joint will subject the rivets to?
Shear Loads
Name three basic metal aircraft designs.
Monocoque, Semi-Monocoque, Reinforced Shell
What is the purpose of formers, stringers and longerons?
To help the skin hold its shape.
What are the 2 forms of Heat Treatment?
Solution
Precipitation
True or false. Machine screws can be both structural and non-structural.
TRUE
Name 6 forces/stresses acting upon sheet metal structure.
Tension, Torsion, Compression, Shear, Bending, Bearing
What is rivet pitch?
Is the distance between the center of adjacent rivet holes in a row.
A stressed skin structure that is made in the form of a single shell with all its strength in its outer skin is called a ____________ structure.
Moneque
Aluminum (Is or Is Not) susceptible to corrosion.
IS
Sheet metal should be bent __________ to the grain direction.
Against or Perpendicular
What is travers pitch? Travers pitch should be _____ of rivet pitch.
Is the distance between rows of rivets in a multiple row seam.
75%
What is a “Neutral Line” or “Neutral Plane”?
There is a plane that remains neutral. It lies at 44.5% of the thickness of the metal from the inside radius of the bend.
What does the T4 temper designation stand for?
Solution heat treatment, followed by natural aging by room temperature. Pg.72 figure 2-11 in airframe 1
What is the purpose of Heat Treatment?
To make the alloy stronger.
What is the standard fix for cracks in sheet metal?
Stop Drilling
Patches