Sheet Metal Board Notes
A 4/32 rivet will use what drill bit and what color Cleco?
#30 bit, copper Cleco
A 3/32 rivet will use what drill bit and what color Cleco?
#40 bit, silver Cleco
How do you find the width of the shop head (bucktail) on a rivet?
1 1/2 × diameter of rivet
5 most important alloying agents and their identifying numbers.
1. Aluminum 2. Copper 3. Manganese 5.Magnesium 7. Zinc
5 types of stresses
1. Shear 2. Tension 3. Torsion 4. Compression 5. Bending
Drill tip angle for hard metal?
118°
Drill tip angle for stainless steel?
140°
All rivet lengths are measured in _______.
16ths
The primary alloying agent of 2024-T36 is indicated by the number....
2
What is the tolerance for edge distance when installing rivets?
2-4 × diameter of rivet
What is the most common skin found on aircraft?
2024
What is the most common rivet used in aviation?
2117
What is the most common rivet and skin combination found on aircraft?
2117 rivets and 2024 skin
Which part of the MS2117-T36-4-3 designation indicates the length of a rivet?
3 in 16ths
How do you determine the diameter of a rivet when given the thickness of the metal?
3 × thickness of the thickest sheet
What is the tolerance for spacing when installing rivets?
3-12 × diameter of rivet
All rivet diameters are measured in _______.
32nds
Which part of the MS2117-T36-4-3 designation indicates the diameter of the rivet head?
4 in 32s
Drill tip angle for soft metal?
90°
What is a Rivnut?
A threaded rivet
Which part of the MS20426 AD 4-3 designation indicates the alloying metal of the rivet?
AD
When fabricating parts from Alclad 2024-T3 aluminum sheet stock,
All scratches, kinks, tool marks, nicks, etc. must be held to a minimum
A 5/32 rivet will use what drill bit and what color Cleco?
#21 bit, black Cleco
Clad Aluminum alloys are used in aircraft because they...
Are less subject to corrosion than uncoated aluminum alloys.
A 2117 rivet will have a _________ marked on the head.
Dimple
2117 alloyed rivets will have what marking and what letter designation?
Dimple marking, AD designation
What should be done to the metal before installing a MS20426AD 4-3 rivet?
Dimple or countersink
2024 alloyed rivets will have what marking and what letter designation?
Double Dash marking, DD designation
What is a stop drill?
Drilling a point in a cracked surface that prevents the crack from spreading.
Where will you find stainless steel rivets?
Firewalls and exhaust
A MS20426-T36-4-3 rivet will have a _____________ head.
Flush
The aluminum alloys used in aircraft construction are usually hardened by what method?
Heat Treatment
How should you drill stainless steel?
High pressure, low speed
What is a drill stop?
Keeps the drill bit from going too far or through material and damaging parts that are behind.
How should you drill soft metals?
Low pressure, high speed
How do you find the length of a driven rivet?
Material thickness + shop head
When bending sheet metal, bend the metal (parallel/perpendicular) to the grain.
Perpedicular
1100 alloyed rivets will have what marking and what letter designation?
Plain head, A designation
5056 alloyed rivets will have what marking and what letter designation?
Raised cross marking, B designation
2017 alloyed rivets will have what marking and what letter designation?
Raised dot marking, D designation
When repairing a small hole on a metal stressed skin, the major consideration in the design of the patch should be...
Shear strength of the riveted joint
Define a joggle in sheet metal.
Small offset formed to allow one part to overlap another
In Alclad 2024 - T3 the "T" indicates the metal has been _______.
Tempered
You would use countersinking on (thick or thin) metal?
Thick
When countersinking, the metal must be (thicker or thinner) than the rivet head?
Thicker
You would use dimpling on (thick or thin) metal?
Thin
A MS20470 rivet will have a ___________ head.
Universal
What is a Clevo?
Used to temporarily hold two pieces of sheet metal together
Define a joggled rivet.
When a rivet almost, but not completely, shears.
When do you use CheryMax or Olympic lok rivets?
When only one side of the material being riveted is accessible.
