Sheet Metal and Non-metallic Structures

Question 1

What is done with the rivet head stem when a self plugging rivet is installed?

Answer 1

It is pulled until it is broken off, then trimmed flush with the rivet

Question 2

Describe the correct dimensions on a properly formed rivet head.

Answer 2

1/2 Diameter tall, 1 1/2 Diameter wide

Question 2

Give an example of a self plugging mechanical lock rivet.

Answer 2

CherryLOCK, CherryMAX, OlympicLOK, HuckLock

Question 3

What is a bonded honeycomb construction?

Answer 3

Two relatively thin, parallel face sheets bonded together and separated by a relatively thick, lightweight core

Question 4

Name two core materials used in special applications of bonded honeycomb construction.

Answer 4

Kraft paper, thermoplastics

Question 4

Name two causes of delamination or debond of a honeycomb construction.

Answer 4

Matrix cracks
High or low energy impacts
Liquid ingestion

Question 4

What is done with the damaged area in bonded honeycomb?

Answer 4

The damaged area must be removed

Question 5

What is a potting compound repair used for in bonded honeycomb?

Answer 5

Hole filling

Question 5

What will cause crazing in transparent plastic panels/ windshields?

Answer 5

Stress, improper handling, and harmful cleaning solvents

Question 6

What should be done to twist drills that are to be used for drilling completely through plexiglass?

Answer 6

The drill must be free from nicks and burrs that would affect the surface finish. Grind the drill with an included angle of 150°. The rake angle should be zero in order to scrape, and not cut.

Question 7

What calculations must be made when bending sheet metal?

Answer 7

Bend allowance and setback

Question 8

What must be done when two bends intersect?

Answer 8

Relief holes must be drilled at the intersection

Question 9

What methods are used in forming metals?

Answer 9

Bending
Bumping
Crimping
Folding
Stretching
Shrinking

Question 10

How do you determine the total length of a solid rivet for installation?

Answer 10

Grip length plus 1-1/2 times the shank diameter

Question 10

What factors are used to determine setback?

Answer 10

Material thickness and the bend radius

Question 10

What is the purpose of lightening holes cut in rib sections?

Answer 10

To reduce weight and improve rigidity

Question 11

What is joggle?

Answer 11

It is the offset formed on a part to allow clearance for a sheet or another mating part

Question 12

How do you determine the proper materials used for a repair of an all metal aircraft?

Answer 12

Use the same type and thickness as the material in the original structure

Question 13

What is the edge distance and spacing for single row of protruding head rivets?

Answer 13

ED - Two times the diameter
Spacing - Three times the diameter

Question 14

Describe the rivet head markings for A, B, D, AD, DD rivets.

Answer 14

A- Plain
B- Cross
D- Raised Dot
AD- Dimple
DD- Raised Double Dash

Question 15

Describe the criteria for replacement of a 2024 rivet with a 2117 rivet for general repairs.

Answer 15

For 5/32 or less diameter, use the next larger size rivet, assuming spacing and ED meet minimum requirements.