Sheet Metal and Non-Metallic Structures

Question 1

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

Answer 1

The grip length +1.5 x the rivet diameter

Question 2

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

Answer 2

The stem is pulled until it snaps off and the remaining projecting part is trimmed flush with the head

Question 3

Give examples of self plugging mechanical lock rivets

Answer 3

Cherry Lock, Cherry Max, Cherry SST, Hulk Lock, Olympic Lock

Question 4

What methods are used in forming sheet metal ?

Answer 4

Shrinking, Stretching, Crimping, Bumping, Folding

Question 5

What factors are used to determine setback ?

Answer 5

Bend radius and material thickness

Question 6

What calculation must be made when bending sheet metal ?

Answer 6

Bend allowance and setback

Question 7

What must be done when two bends intersect to prevent cracking ?

Answer 7

Relief holes are drilled at the intersection

Question 8

What is a joggle ?

Answer 8

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

Question 9

What is the purpose of lighting holes cut in the rib section ?

Answer 9

To reduce weight and increase stiffness

Question 10

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

Answer 10

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

Question 11

What are the correct dimensions on a properly formed rivet head ?

Answer 11

1 1/2 of the shank diameter in width, 1/2 of the shank diameter in height

Question 12

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

Answer 12

Use the same type and thickness of the material that was originally being used

Question 13

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

Answer 13

Edge 2 x diameter, Spacing 3 x diameter

Question 14

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

Answer 14

5/32nd or less in diameter, use the next larger size 2117 rivet and the edge/spacing distance meets the minimum requirements

Question 15

What is the difference between the tools required to pull a Cherry Lock rivet and a Cherry Max rivet ?

Answer 15

Cherry Lock - Require different tool for each size
Cherry Max - Same tool for all

Question 16

How can a mechanic determine weather the countersink for a flush rivet should be dimpled or drilled ?

Answer 16

By the thickness of the top sheet, thin sheets are dimpled, thick sheets are countersunk

Question 17

What action is taken to prevent cracks from forming while dimpling magnesium or some hard sheet metals ?

Answer 17

Hot dimpling equipment is used to preheat and soften the metal before the dimple is formed

Question 18

What type of damage can occur when using a rivet set that does not properly fit the rivet ?

Answer 18

The rivet head and the sheet metal may be damaged

Question 19

Why is it important to use the proper bucking bar when performing sheet metal riveting ?

Answer 19

Too large - Difficult to control and you can damage the sheet metal
Too small - Will not properly upset the rivet before work hardening occurs

Question 20

What procedure should be followed to properly remove a solid shank rivet ?

Answer 20

Center the punch the rivet and drill to the base of the rivet head using the same size or one size small drill, then use a pin punch to tip off the rivet head