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Flashcards in Sheet Metal Deck (29):
1

Name several methods for forming sheet metal

Bending or folding, stretching, shrinking, bumping, and crimping

2

What are the dimensions of a properly formed rivet head

Head should be 1 1/2 times the shank diameter and 1/2 the shank diameter in width

3

Describe the markings found on the heads of A, B, D, AD,and DD rivets

• A plain – 1100 – Pure aluminum
• B cross – 5056 - Magnesium
• AD raised dot – 2117 – Universal
• D dimple – 2017 – “Ice box”
• DD double dash – 2024 – “Ice box”

4

What happens to the stem of a self- plugging rivet when the rivet is installed

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

5

Name at least three types of self plugging mechanical lock rivets

CherryMax , CherryLOCK, and OLYMPIC LOK

6

What is the difference between the tools required to pull a CherryLOCK rivet and a CherryMax rivet

CherryLOCK rivets require a tool for each different size and head shape while one pulling tool will set any size CherryMAX rivet

7

Which of the five stresses is the most common cause of rivet failure

Shear

8

Describe the process for determining the total length of a solid rivet for a particular installation

Add grip length plus 1 1/2 times the rivet diameter

9

What minimum edge distance and spacing should be used for a single row of protruding head rivets

No less than two rivet diameter from the edge and no less than three rivet diameter apart

10

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

If to small rivet head may be damaged if to big sheet metal will be damaged

11

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

Center punch the rivet
Drill just to the base of the rivet head with same size or one size bigger drill bit
pin punch to tip off the rivet head
Then drive the remaining shank out of the hole

12

What are the two special calculations that must be made when bending sheet metal

Setback and bend allowance

13

What factor must be considered in order to determine setback

The thickness of the metal and the bend radius

14

What is done to a corner where two bends intersect to prevent cracking

Relief holes are drilled

15

What are the toe reasons for installing a lightning hole in a sheet metal wing rib

Reduce weight and increase stiffness

16

Describe a jiggle and explain its function

Small offset near the edge of a piece of sheet metal . Allows one sheet of metal to overlap another while maintaining a flush surface

17

When repairing an all metal aircraft how do you determine what metals should be used

Always use same type and thickness as the original structure

18

What is the major type of damage to aluminum structures that is caused by exposure to the weather

Corrosion

19

What causes honeycomb structure to delaminate

Moisture

20

What is used for hole filling in bonded honeycomb repair

Potting compound

21

What size drill should be used for common shank rivet diameters of 3/32inch ,4/32 / 1/8 inch , and 5/32 inch

3/32 rivet # 40. For a 4/32 or 1/8 rivet #30. For a 5/32 rivet # 21

22

What type of rivet may be used to replace a round head rivet in an aircraft

Universal head rivet

23

What are two types of resins used in aircraft construction

Thermoplastic and thermosetting

24

What are two parts of an epoxy matrix material

Resin and hardener

25

What is necessary to cure a thermosetting resin

Heat

26

The rivet to use for joining two sheets of metal should have a diameter of what

3 times the thickness of the thickest sheet being joined

26

What is the distance between the center of the rivet holes in a single row of rivets is called

Rivet pitch

27

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

The thickness of the top sheet thin sheets are dimpled well thick sheets are countersunk

28

The shank of a rivet should stick out the the sheet by

1 1/2 times shank diameter