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Module 7 > 7.3: Tools > Flashcards

7.3: Tools Flashcards

1
Q

What and why are screwdriver shanks sheathed?

A

With carbon steel to protect users on electrical systems

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2
Q

What is done to the tip/blade of a screwdriver for protection?

A

Hardened

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3
Q

What are flat head screwdrivers typically used for on aircraft?

A

Quick release fasteners

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4
Q

How are phillips screwdrivers compared to reed and prince/frearson?

A

They have a blunt end a slightly larger centre in the cross compared to reed/frearson

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5
Q

What is the point angle of phillips screwdrivers?

A

30 degrees

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6
Q

What are the numbers of smallest screwdrivers and what are they for?

A

00, 000, 0000 for watchmakers

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7
Q

What is the point angle of reed and prince?

A

45 degrees

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8
Q

What are the sizes for freason screwdrivers?

A

Size 1 is for #5 and smaller
Size 2 is for #6 and larger

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9
Q

What are pozidriv screwdrivers comapred to phillips?

A

They are an improved version with more contact area

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10
Q

What advantage does torx screwdrivers have>

A

They have an advantage when removing screw clogged with debris, paint

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11
Q

What are internal hex screws?

A

Allen key screws

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12
Q

What is torq set?

A

Like phillips but the cross is offset ensuring greater torque which increases screw security where the torque loading is critical

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13
Q

What is mortorq?

A

Four wings that are curved and fit into the matching screw head allowing full contact with an ability for a higher strength shallower recess to be made

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14
Q

What is hi-torque?

A

Has a straight almost slotted arrangement, with curved walls allowing much higher torque

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15
Q

Where is the carpenter or claw hammer used on the aircraft?

A

It is not used on the aircraft

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16
Q

How are hammers classified by?

A

Pein
Weight
Shape
Face

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17
Q

What are the common types of hammers used in aviation?

A

Ball pein
DIN general purpose
Soft face mallet

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18
Q

What are ball pein hammers made from?

A

High-grade drop forged steel which is fully heat treated

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19
Q

What are done to the handle of pliers and why?

A

Sheathed to protect operators from electric shock

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20
Q

How are pliers classified?

A

By their function and the type of nose they have

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21
Q

What are single fixed joint pliers like?

A

Half cut out and placed inside each other with a pivot point installed

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22
Q

What are toggle compound pliers like?

A

Has a toggle point with the single fixed joints to allow the user to apply more leverage

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23
Q

What are lap joints?

A

Both halves of the pliers are made and jointed on top of each other for leverage when cutting

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24
Q

What are multi-grip pliers?

A

Curved grooves that employ a slip joint which makes them adaptable to most situations

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25
Q

How are vice grip pliers adjusted?

A

By a knurled screw located in the end of the main handle

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26
Q

What is the threaded screw of the C or G clamp and why?

A

An ACME thread for strong clamping force

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27
Q

What are classifications of spanners?

A

Open end spanner
Ring spanner
Combination spanner
Ratchet handles and breaker bars
Sockets
C spanner
Strap wrench

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28
Q

Open end and crows foot spanners can be either what?

A

Hex open end
Bi hex open end

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29
Q

What is the common and maximum angle open end spanners are set at?

A

Mostly 15 degrees but can be up to 90

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30
Q

What does crow foot spanners have an opening for?

A

Insertion of a ratchet handle

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31
Q

What type of spanners are good for securing bleed nipples or pipework?

A

Bi-hex open end and crow foot spanners

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32
Q

When should adjustable spanners be used on an aircraft?

A

When a commercially available item is fitted using non-aircraft standard fasteners

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33
Q

What type of spanner is good for close quaters?

A

Ratchet ring spanners

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34
Q

What are the common sizes for ratchet handle drive?

A

1/4 in
3/8 in
1/2 in
3/4 in

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35
Q

Do breaker bars have a rachet mechanism?

A

No

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36
Q

What is the extension bar in a socket set?

A

Fitted between the ratchet handle and socket and provides a long reach for the socket into hard to access areas

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37
Q

How are socket spanner handles and socket heads held together?

A

Through a light spring loaded poppet

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38
Q

What are C spanners broken down into?

A

Fixed C-spanner
Adjustable C-spanner
C-pin spanner
Pin face spanner

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39
Q

What’s an example a C-spanner use on aircraft?

A

Oleo strut

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40
Q

How is an adjustable C-spanner constructed?

A

The middle of C split and connected by a pin forming a hinge

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41
Q

How is a strap wench constructed?

A

Has a woven nylon strap impregnated with a powdered resin to help grip

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42
Q

What example of use does a strap wrench have on aircraft?

A

Can be used on a galley water filter that is supposed to be hand tight but has become tight through time

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43
Q

What are type 1 torque wrenches?

A

Wrenches that indicate torque on a mechanical scale, dial or electronically so it is up to the operator to stop at desired torque

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44
Q

What are type 2 torque wrenches?

A

Fixed to an adjustable or pre set torque value so an audible, visible and/or feel is used for desired torque

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45
Q

List of type 1 torque wrenches?

A

Flex bar torque wrench (Class A)
Wrench with a dial indicator (Class B)
Wrench with electronic measurements (Class C)
Screwdriver with indicator (Class D)
Screwdriver with a digital scale (Class E)

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46
Q

How often are flex bar torque wrenches used (Class A)?

A

Rarely due to susceptibility to damage

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47
Q

How often are wrenches with a dial indicator used (Class B)?

A

Used mainly in workshops due to bulky nature and the dial being challenging to read

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48
Q

How often are wrenches with electronic measurements used (Class C)?

A

Used more often but most have an audible signal for desired torque, making them type 2

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49
Q

How often are screwdrivers with indicator used (Class D)?

A

Not used

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50
Q

How often are screwdrivers with a digital scale used (Class E)?

A

Not used

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51
Q

List of type 2 wrenches?

A

Adjustable wrench with indicator (Class A)
Fixed torque wrenches (Class B)
Adjustable wrench without indicator (Class C)
Adjustable screwdriver with indicators (Class D)
Fixed screwdrivers (Class E)
Adjustable screwdrivers without indicators (Class F)
Adjustable wrench with a flexing bar (Class G)

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52
Q

How common is the adjustable wrench with indicator used (Class A)?

A

Most commonly used torque wrench

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53
Q

What is the mechanism of an adjustable wrench with indicator?

A

It has a vernier scale on the barrel and has a clicking sound with a ratchet. The clicking sound is done through a tilting block arrangement inside the torque wrench with a spring adjusted to reach desired tension on the pivot block

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54
Q

How often are fixed torque wrenches used (Class B)?

A

Used in the workshop environment

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55
Q

How are fixed torque wrenches set to desired torque?

A

Through co axial connectors that breaks on achieving set torque

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56
Q

How is torque set on an adjustable wrench without an indicator (Class C)?

A

It is set internally and is fixed for the duration that it is in service

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57
Q

How does the adjustable screwdrivers indicate torque when done (Class D)?

A

Involves the screwdriver slipping when desired torque is reached, a clicking sound and electronic settings

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58
Q

What are fixed (Class E) and adjustable screwdrivers with indicators (Class F) used for?

A

Used for lower torque values and is adjusted internally

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59
Q

How popular are adjustable wrench with a flexing bar?

A

Reasonably popular and are used for much higher torques, with audible and visual indicators

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60
Q

What is torque?

A

The moment force, with the force being measured by a torque wrench is called a reaction force

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61
Q

What are the units for torque?

A

Nm or lbs-ft
lbs-inch for smaller forces

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62
Q

How to convert Nm to lbs-ft?

A

Divide Nm by 1.356

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63
Q

How to convert lbs-ft to lbs-inch?

A

Multiply lbs-ft by 12

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64
Q

Why should you not soak a torque wrench in solvent?

A

You can ingress the tool

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65
Q

What are rules made of and what sizes?

A

Tempered carbon steel or satin finished stainless steel and come in either 6 or 12 inches

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66
Q

What angle does the combination of a square head and rule use to scribe lines?

A

45 degree angle

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67
Q

What is the scriber in the combination set held by?

A

Held frictionally in the head by a small brass bushing

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68
Q

What are common sizes with engineers squares?

A

3 to 12 inches

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69
Q

What are engineers squares used to?

A

Mark 90 degree angle
Check internal and external angles

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70
Q

How are scribers constructed?

A

Made of tool steel, 10 to 100 cm long and have one end 90 degrees bent for marking holes

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71
Q

What materials should dividers or compasses not be used on?

A

Metal as it can cause permanent damage

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72
Q

What are callipers used for?

A

Measuring distances and diameters or comparing distances and sizes

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73
Q

What are two types of callipers?

A

Inside
Outside

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74
Q

What are the two types of punches generally used?

A

Solid
Hollow

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75
Q

What are punches usually made out of?

A

Hardened steel, but a type of punch called a drift can be made out of copper or bronze to minimise damage to objects that are drifted out

76
Q

What is a prick punch?

A

Has a sharp tip ground to an angle of 30-60 degrees and is used to mark a piece of metal and show where the holes need to be drilled initially

77
Q

What is a centre punch?

A

Ground angle of 60 degrees for light work and 90 degrees for general work, after a prick punch

78
Q

What is an automatic centre punch?

A

Has an adjustable spring loaded trip mechanism and has an angle of 60 degrees for light work and 90 degrees for general work

79
Q

What are beryllium copper and brass punches used for?

A

Where a risk of sparking is present if a hardened steel punch was used

80
Q

What is a role pin punch used for?

A

The removal of roll pins and not used as a pin punch

81
Q

What are straight snips used for?

A

Used for cutting straight lines when the distance is not great enough for a guillotine and for cutting the outside of a curve

82
Q

What types of snips are used for the inside of curves or radii?

A

Curve
Hawksbill

83
Q

Can snips be used for heavy sheet metal?

A

No

84
Q

What are the colours for handles in snips?

A

Yellow aviation snips cut straight
Green aviation snips curve right
Red aviation snips curve left

85
Q

What is the hacksaw range in inches?

A

From 6 to 16 inches with 12 being the most common

86
Q

What are the common pitches of teeth commonly available?

A

14 TPI (coarse) is used for steel
18 TPI (coarse) is preferred for solid stock aluminium, bearing metal, tool steel and cast iron
24 TPI (medium) when cutting thick walled tubing, pipe, brass, copper
32 TPI (fine) is used for thin walled-tubing and sheet metal

87
Q

How are hacksaw blades mounted?

A

On the frame on studs and must have the teeth pointed forward, meaning the cutting direction is on the forward stroke

88
Q

How are the junior hacksaw blades teeth facing forward?

A

Teeth facing towards the handle with the cutting direction towards the operator, and the saw frame springy and compressing

89
Q

What is the file made out of and how is it treated?

A

Made of high grade carbon steel that is tempered to give strength and durability, with the exception of the tang, which undergoes further heat treatment to make it softer and less brittle

89
Q

What are flat files in structure?

A

Rectangular in cross section and tapered in thickness for the last 1/3 of their length towards the tip, with both faces double cut and both edges single cut

90
Q

What are hand files in structure?

A

Rectangular in cross section and tapered in thickness but parallel for their full length. The faces will have double cut teeth but only one of the edges will be single cut and the other is pain and referred to the safe edge

91
Q
A
91
Q

What is the structure square and triangle?

A

Double cut teeth on all edges

92
Q

What is the structure of half round files?

A

Double cut on the flat face and single cut on the half round face

93
Q

What are single cut file teeth angle?

A

65 to 85 degrees to the centreline

94
Q

What are the double cut teeth angles?

A

First set usually 40-50 degrees that of the crossing teeth is 70-80 degrees

95
Q

What are file teeth rake pattern?

A

Negative rake so that the cutting stroke is forward stroke only

96
Q
A
97
Q

What is the strength of a file dictated by?

A

Pitch of the teeth

98
Q

What are the common grades of cuts in files?

A

Bastard cut
Second cut
Smooth cut
Rasp cut

99
Q

To prevent rusting, what should be used on a file?

A

Oil, but not too much where the effectiveness of the file is reduced when first used

100
Q

What are the most common types of pneumatic drills?

A

Piston grip drill
Straight drill
Right angle drill
45 degree angle drill

101
Q

What are the classifications of drill bits?

A

Twist drill
Countersink
Counterbore
Flat bottom boring
Speciality

102
Q

How is the tapered shank drill engaged in a socket?

A

They have a taper called the morse taper. At the end of the taper shank of a drill is a tongue called a tang, with the tang engaging in the slot when the shank is fitted into the socket

103
Q

What are flutes on drill bits?

A

Helical grooves cut or formed in the body of the drill to permit removal of chips produced at the cutting edge and allows cutting fluid to reach the cutting lips

104
Q

What is the margin on drill bits?

A

The narrow surface along the flutes that determine the size of the drill and keeps the drill aligned

105
Q

What is the land on drill bits?

A

The peripheral portion of the body between adjacent flutes which provide torsional strength

106
Q

What is the land clearance on drill bits?

A

The area relieved of material behind the margin thus providing clearance as to not rub against the wall of the hole

107
Q

What is the point on a drill bit?

A

Consists of:

-Chisel Edge
-Cutting edge
-Flank
-The face
-The web

108
Q

What are the flanks on drill bits?

A

Behind the cutting edge and extend from the outside circumference of the drill and extend to the middle where both flanks meet in the middle to form the chisel edge and web

109
Q

What is the chisel edge?

A

Does not cut penetrate the workpiece displacing materials and provides thrust to the drill bit

110
Q

What is the web in a drill bit?

A

Measured as the thickness across the base of the flute and maybe known as core thickness. It increases down the drill bit for strength and rigidity

111
Q

What type of drill bit do most engineers use?

A

Light type

112
Q

What is the point angle on drill bits?

A

The angle of the cutting edge

113
Q

What do drill point angle correlate to material cuts?

A

118 degrees: Aluminium and Mild steel
135 degrees: Aluminium, high tensile steel ,stainless steel and sheet steel
30 to 70 degrees: Plastic materials, hard rubber and fibre

114
Q

What are drill bits determined by?

A

Type
Material
Size
Cutting angle

115
Q

What is split point twist drill bit involve?

A

The reduction in web thickness at the point of a standard drill bit to prevent wander of the drill bit

116
Q

What are some split point advantages?

A

Faster drilling
Less force required to cut through material
Creates smaller/less chips

117
Q

What angles are microstop countersink cutters available?

A

82 degrees
100 degrees
120 degrees

118
Q

What is spot facing?

A

A method used for cutting a flat area or seat for a bolt head, or nut on a contoured or uneven surface

119
Q

What are reamers?

A

Used to go through pre drilled holes to get very accurate hole diameters

120
Q

What are the two main types of reamers?

A

Hand reamers
Machine reamers

121
Q

Why should reamers be handled correctly?

A

They are hardened to the point of being brittle

122
Q

What are the cylindrical parts of most straight reamers used for?

A

Not cutting edges, but instead just grooves cut for the full length of the reamer body, providing a way for chips to escape

123
Q

What are cutting edges normally ground to a bevel of?

A

45 degrees +-5

124
Q

Can reamer flutes be withdrawn by turning it in the reverse direction?

A

No as the chips can be forced in the surface and care the hole

125
Q

How should a hand reamer be lubricated?

A

Should continuously be turned clockwise with oil added

126
Q

With machine reamers, what do they have instead of a square drive?

A

They have a morse taper shank which is fitted onto a sleeve

127
Q

What is a tap made of?

A

They are made of hard tempered steel

128
Q

What taps and dies standards?

A

National Coarse
National Fine
National Extra Fine
National Pipe

129
Q

What are taper taps used for?

A

The begin the tapping process as it is tapered back six to seven threads, it is the only tap needed when tapping holes that extend through thin section

130
Q

Are bottoming taps tapered?

A

They aren’t tapered and are used to cut full threads to the bottom of a blind hole

131
Q

What are two types of dies?

A

Solid dies
Adjustable dies

132
Q

How much more flutes do dies have to form a cutting edge?

A

Three or more flutes to form cutting edges on the internal threads and cavities for the removal of chips, with champers on the first few threads on the leading edge to facilitate easy starting

133
Q

What are features if a mounted pillar drill?

A

Usually belt driven
A three jaw chuck with a shank capacity 13 mm or less, and the chuck held in place by a morse taper
Their spindle speeds range from a few hundred revs per minute to a few thousand revs
Hand feed of the drill bit is used for drilling small holes

134
Q

What are floor mounted pillar drill features?

A

Checked for levelness
It is belt or gear driven
A three jaw chuck with a drill shank capacity of 65mm
Has a wide range of spindle speeds

135
Q

Should drills run faster with softer or harder materials?

A

Faster with soft materials

136
Q

What are materials for soluble oil?

A

Mild steel
High carbon steel
Stainless steel

137
Q

What are materials for kerosene?

A

Copper and brass
Aluminium

138
Q

What materials are best worked dry?

A

Cast iron

139
Q

How to test an abrasive wheel?

A

Should be gently tapped with a light, non metallic instrument. If it sounds dead, it should not be used

140
Q

How should abrasive wheels fit on a spindle with the spindle nut?

A

Should fit freely on the spindle, with the spindle nut tightened just enough to hold the wheel in place without distorting the flange

141
Q

What should you never use to clamp a hand-held grinder?

A

A vice

142
Q

What is the air supply on tools?

A

90-110 psi

143
Q

What doe the electrically driven compressor have due to being susceptible to condensation and water ingress?

A

Has a water trap built in it for the air supply

144
Q

What are the angle drills head angles?

A

30 degrees
45 degrees
90 degrees

145
Q

How are angled drill motors drill bits attached to the drill head?

A

Using a collet

146
Q

How is the offset drilling head ordered?

A

Spindle direction
Motor speed
Offset dimension

147
Q

What are drill stops used for?

A

Regulate hole depth, cushion the breakthrough, eliminate surface marks and reduce drill breakage

148
Q

What are hand held drill guides used for?

A

Keeps the drill at 90 degrees to the surface. It has a clear plastic housing and hardened steel bushings that screws into the plastic housing

149
Q

What pressure do pneumatic rivet guns operate at?

A

6.5-7kg

150
Q

How much blows per minute do slow hitting rivet runs use?

A

900 to 2500 BPM and are the most common

151
Q

What are four types of micrometres?

A

Internal
External
Depth
Thread

152
Q

Where is the measurement of a metric micrometre?

A

Between the face of the anvil and the end of the spindle

153
Q

What are the range of micrometres?

A

25mm

154
Q

Why is the three point internal micrometre used?

A

A more accurate version of the standard internal micrometer

155
Q

What is the DTI accuracy?

A

0.01mm or 0.001 in

156
Q

What are two types of DTI?

A

Plunger DTI
Lever DTI

157
Q

What are DTI’s used for?

A

Measure the alignment of shafts or smoothness of surfaces

158
Q

How should DTI’s be supported?

A

By magnetic stand or clamps

159
Q

Do lever DTI’s have a smaller or larger measuring range than plunger DTI’s?

A

Smaller

160
Q

What is a typical application for go/no-go gauges?

A

Checking the control cable terminal fittings after swaging

161
Q

What are lubricants broken down into?

A

Greases
Oils
Speciality lubricants

162
Q

What are areas where lubricants broken down into?

A

Airframe systems
Engine and gearbox systems

163
Q

What are the most commonly used grease fittings on aircraft?

A

Zerk grease nipples

164
Q

What are flush type grease nipples used for?

A

Areas where clearance is a problem

165
Q

What are injector needles used for?

A

Used to grease flush nipples

166
Q

What are the two assumptions electromagnetism is based on?

A

The strength of an electromagnetic field is proportional to the amount of current that flows in the coil
Voltage, resistance and power all relate to a flow of current and if current is known, then all other values can be found

167
Q

What is a PMMC (Permanent Magnet Moving Coil)?

A

A pointer deflecting being proportional to the current flow, acting like a meter for ammeters, voltmeters and ohmmeters

168
Q

What is there at the front of the case on PMMC?

A

A slotted screw for zero adjustments

169
Q

What are other two features on PMMC for accuracy and efficiency?

A

An iron core placed inside the coil to concentrate the magnetic fields which will give more linear movements, also generating eddy currents to give some damping and reduce oscillations
Curved pole pieces are attached to the permanent magnet to ensure the turning force on the coil steadily as the current increases

170
Q

What is full scale current?

A

The amount of current that must flow through the meter coil to cause a full scale deflection

171
Q

What is the measurement of meter sensitivity?

A

The reciprocal value of the full scale current and represents the total amount of resistance for each volt needed to produce a full scale current

172
Q

What are high sensitivity meters used for?

A

Application that require measurement of very small electrical quantities of small electrical quantities

173
Q

How are ammeters always connected and why?

A

In series as in parallel it would give an incorrect measurement and damage the meter from too much current

174
Q

What is a shunt?

A

A meter connected in parallel to a meter to increase the amount of current it can measure, by being designed to carry a fixed proportion of the current to be measured

175
Q

How much mA will a meter need to be measuring for a shunt resistor to be needed?

A

More than 1 mA

176
Q

What is the current sensitivity and resistance of a standard moving coil?

A

Current sensitivity of 1 mA and a resistance of 50 ohms

177
Q

What are remotely located external shunts used for?

A

High current cables

178
Q

What range should you start with when using an ammeter?

A

Highest range

179
Q

What is a voltmeter?

A

A moving coil meter with a resistor connected in series, which limits the current flow to a value, resulting in a full scale deflection

180
Q

How is a voltmeter connected?

A

Parallel

181
Q

How can you tell if a voltmeter is connected correctly?

A

If a voltmeter can be removed from the circuit without opening it

182
Q

Why do voltmeters have very high resistances?

A

To limit current flow through the voltmeter and the voltmeters impact on the circuit

183
Q

What is an ohmmeter?

A

A moving coil with a small battery to provide voltage that creates a current to operate movement, as it measures resistance

Module 7 (13 decks)

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