Module 7.3 Flashcards
What is the benefit to socket drive screw drivers?
Interchangeable drill heads, meaning a need to carry round all different drivers
What are the components of a screw driver?
Blade/tip, shank, handle
What is different about the material in the shank than that in the tip?
They are both made from the same material (alloy) however, the tip is harder than the shank
How is the blade size classified?
Width and length
How much of the screw slot must the screw driver fill to not damage the head?
75%
What is the angle of the tip on a Phillips driver?
30 degrees
How are Phillips screw driver sizes classified?
By a number which refers to head size.
Smaller number = smaller head
What is the angle of the tip of a reed and prince screw driver?
45 degrees
What are offset screw drivers used for?
In areas of limited space
What is the advantage of a pozidriv screw and screwdriver
Improved Phillips. It allows higher torque due to more surface area
Why is it important to be able to tell the difference between a reed and prince and a Phillips?
They have different heads, although they look similar.
If the incorrect screwdriver is used then the head of the screw can be stripped.
What is the advantage of a Torx screw head?
Can apply an increased torque with less effort, this is due to a high amount of contact area.
less likely to cam-out. (slipping)
What are Torx also known as?
Star drives
What is another name for internal hex?
Allen key
How can you determine the size of a tri-wing screw?
Stamped on head, 0-15
What does the head of a torq-set screw look like?
Like a Phillips but the cross is offset
What is a mortorq screw head?
4 wings. High torque can be applied
What are ball pein hammers manufactured from?
High grade steel
Where are DIN hammers commonly found?
In aircraft ‘flyaway’ mechanic tool kits
Soft faced hammers/mallets are designed for what purpose?
Transferring a force to an object without damaging the surfaces
How are soft faced mallets graded?
Weight of the head
What are the 3 less common hammer types?
- Sheet metal
- Dead blow
- Copper and rawhide
What hammer has no place in an aircraft engineers tool kit?
Carpenters/claw hammer
How are pliers made? Material, process etc
High quality alloy steel, with cutting edges that have been induction hardened
How are pliers classified?
Function and type of nose
What are the 4 types of aircraft plier joints?
- Lap
- Fixed
- Toggle
- Slip
What does a lap joint plier allow?
Greater leverage
What is the use of diagonal pliers?
Cutting material
What are combination/linemans pliers used for?
General use
What are long nose pliers used for?
Smaller, detailed work
What are the types of locking specialty pliers?
Multigrip (Swan necks), Vice grip, circlip
What makes swan necks adaptable to most situations?
Slip joint
In vice grip pliers, what does the toggle action do?
Clamp/lock the jaws
Circlip pliers are used for what purpose?
Fitting and removing circlips
What gauges of locking wire are generally used?
230 mm nad 150 mm
What are the 3 types of vices?
- Metal working
- Hand held
- Machine vices
How is the size of a vice determined?
Jaw width and vice capacity when fully open
What are the two types of metal working vices?
- Fixed
- Rotating
In metal working vices, what is used to protect the metal?
Jaw covers, masking tape
A hand held vice is also known as?
A clamp
What are handheld vices used for?
Holding parts together while an operation takes place
What are machine vices?
Smaller vices that can be moved from one location to another
What is another name for c clamps
G clamps
What is the benefit for ACME threads in C clamps?
Provides a strong clamping force
What is the most common angle of open end spanners?
15 degrees, but they can range 0 - 90 degrees
What nut are open end spanners designed to fit?
Hex nuts
What are the spanner size increments?
1/16’’ typically from 3/16” - 1 1/16”
What is the difference between an open end and a crows foot spanner?
A crows foot has a square drive fitted to receive a ratchet to apply a turning force
What should you not use adjustable spanner on aircraft maintenance?
Not a tight enough grip, can slip and round off the nut
Where may the use of adjustable spanners be acceptable?
On commercially of the shelf items that have non aircraft fittings
What is the common size of adjustable spanners?
- Tool length, 150 mm & 250 mm
- Jaw opening, 20 mm & 30 mm
What side of the head of an adjustable spanner should the turning force be applied to?
The fixed side
What is different about a ring end spanner and an open end spanner?
Ring spanners surround the bolt head or nut
What two variations of ring spanners can you have?
Hex and Bi-hex
What is the benefit of ratchet ring spanners?
Saves time and effort
What is the most important feature of a screw driver handle?
Non-conductive
What are the features of a standard combination spanner?
One end is ring and the other is open
What are the features of a ratchet ring combination spanner?
One end is open the other is a ratchet ring
Ratchet handles are reversible, what does this mean?
Used for installation and removal
What is the difference between a Phillips and a reed and prince screwdriver head?
Phillips is rounded, Reed and prince is sharp
What are the most common square drive size?
1/4, 3/8, 1/2, 3/4”
What screws can a size 1 be used for?
Size 1 #5 or smaller
What screws can a size 2 be used for?
Size 2 #6 or longer
Which component inside the ratchet head changes the direction of movement?
The pawl
What makes breaker bars different from ratchet handles?
There is no ratcheting mechanism and the head can be rotated 180 degrees
What are breaker bars used for?
‘Break’ the torque of the nut/fastener. A ratchet can be used after
How is a socket secured on too the handle?
Spring loaded poppet, this holds the two parts together
What are breaker bars used for?
“Break” the torque of the fasteners/nut. So a ratchet handle can be used to finish.
How is a socket secured on to handle?
Spring loaded poppet holds the two parts
What is a type 1 torque wrench?
Indicates torque via a mechanical dial or electrically. Up to operator to stop at desired torque
How does a type 2 torque wrench indicate that the torque valve had been reached?
Audible, visible signal or feel or a combination
What are the two main types of type 2 wrenches?
-adjustable
-fixed
Once finished with an adjustable torque wrench what should be done?
Put to the lowest setting
When choosing a torque wrench for a torque valve what should be done?
Look for a torque wrench that the torque value falls in the middle of the range
What is the working range of a mechanical torque wrench?electrical?
Mechanical 20-80% of its full range electrical is 10-100%
What is the formula for finding torque applied with an extension bar?
M1=M2*L1/L2
What 2 things can a rule be used for?
Measuring and a straight edge
What does a combination set incorporate?
Rule, square head, spirit level, protractor head, centre head, clamp, 90 degrees and 45 degree lines
How is an engineering square sized?
Length of the inside edge of the blade
What are the 2 features of an engineering square?
-Blade
-Stock
What 3 things can an engineering square be used for?
-Mark lines at 90 degrees
-check internal angles
-check external angles
What are the 2 tips of a scriber?
-angled tip
-straight tip
Why must use of a scriber on al-clad be avoided?
It will damage the protective pure aluminium layer and let corrosive agents in
What are dividers used for?
Arcs and circles, distance between parts and to transfer from a rule
When must dividers not be used?
When marks on lines must be drawn on a metal surface
What are the 2 common types of callipers?
-inside
-outside
What are radius gauges used for?
Measuring internal or external radii for example rounding corners to a stated radius
What principle should be adapted when using feeler gauges?
Go or no go technique
What is the angle of the top on a prick punch?
30 or 60 degrees
What is the purpose of a prick punch?
Used as mark that is to be enlarged by a centre punch before drilling
What type of work is 60 degree tip used for centre punching? What about 90 degrees?
60-light work
90-general work
What is the purpose of an automatic centre punch?
Negates the need for a hammer
What is the purpose of a starting (taper) punch?
To start driving out a bolt pin.Once it almost fills the bolt hole finish with a pin punch
What are pin punches used for?
To drive out rivet shanks
What cut do yellow aviation snips do? Red? Green?
Yellow cut straight
Green cut right
Red cut left
What is a 14tpi hack saw used to cut? What about 18?
14 tpi - cutting steel
18 tpi - solid aluminium, bearing material, tool steel, cast iron etc
What is a 24 tpi hack saw used for? 32 tpi?
24 tpi - tubing, pipe, brass, copper channel and angle iron etc
32 - twin walled tubing and sheet metal
What is a hacksaw blade made of?
High grade steel or tungsten steel
What stroke does a full hacksaw cut on?
Forward stroke away from you
What is the cutting direction of a junior hacksaw?
Towards the operator
When would you use a mini hacksaw?
Used in confined space
What is a file used for?
Used to shape metal by cutting and abrasion
What is the difference between the metal in tang and the nest of the file?
The tang undergoes further heat treatment to make it softer, less brittle and resistant to damage
What is the difference between hand files and flat files?
Hand files are tapered only for thickness through the whole length. Only one edge is cut the other is plain.
Flat files are tapered in the last 1/3 of its length in width+thickness. No safe edge.
What angle are the teeth on single cut files?
65-85 degrees
What angle are both cuts on a double cut file?
70 to 80 degrees and 40 to 50 degrees
What stroke is the cutting stroke of a file?
Forward stroke
What are the 4 grades of cut?
-bastard cut
-second cut
-smooth cut
-rasp cut
(American pattern files)
What set of files are most commonly used by aircraft engineers?
Needle files
How do you keep a file corrosion free?
Applying a light coating of oil
What should be used to clean a file?
Wire brush or file card
What are the 3 filing techniques?
-straight (forward) filing
-cross filing
-draw filing
What is deburring?
Removal of the fine slivers of metal the hang onto the edge of the material
What mustn’t be used to debur a piece of metal? And what should be?
Do not use a file use a handheld deburrer
What are the 3 main types of drills?
Hand drills and braces, pneumatic drills and electric drills
What are the benefits of using a handbrake over a screwdriver?
Allows for higher pressure pushed through to the fastener and a greater torque
Are drill bits controlled items?
They must be accounted for at the end of a shift
What is the purpose of the flute?
To remove swarf from the drilled hole and allows cutting fluid to reach drill tip
What is the shank of the drill?
The plain part of the drill that goes inside the drill chuck
What provides the torsional strength in a drill bit?
The land portion between adjacent flutes
What is the point angle for a drill bit that cuts aluminium and mild steel?
118 degrees
What is the point angle for a drill bit that cuts aluminium, high tensile steel, CRES B sheet steel?
135 degrees
What point angle is used for cutting plastic material?
30 to 70 degrees
Hard rubber and fibre 60 degrees
What does an increased web thickness give a drill bit?
Strength and rigidity
What tool should be used to countersink many rivet holes to the same depth?
Microstop countersink tool
What is the most common countersink angle?
100 degrees
What is the purpose of spot facing?
Method used to cut a flat or seat area for bolt heads
What is back spot facing?
When spot facing must be done in reverse. Work piece cuts back towards spindle.
What is important about the pilot on a spot face and countersinking tool? (Size)
Must be 1/32 inch smaller
What is the purpose of reaming?
Drill bits leave an inaccuracy in size so reaming enlarges the hole to an exact size
In machine reamers what is different about the shank?
Morse tapered shank
What is a key drift used for?
For pushing the reamer out of the sleeve
What reamers are less accurate?
Adjustable reamers
What must be ensured when removing a reamer from a drill hole?
Do not revere the spin of the reaming
What are taps used for?
Cutting internal threads inside a drilled hole
What are the 3 types of hand tap sets?
-taper
-plug
-bottoming
What are the 4 classifications of dies ?
National coarse, fine, extra fine and pipe
What are dies used for?
Cutting external threads on a cylindrical material
What is the purpose of chamfers on the dies?
Facilitate easy starting
What are the 2 types of dies?
-Solid
-Adjustable
What is the stock?
Name of the tool used to turn and hold the die
What is the purpose of caulties of the dies?
Allow for removal of chips
What is the purpose of a collet?
To allow for a tight grip on drill bits on angle drills. Use of larger bits
To ensure safety with electronic tools what precautions should be taken?
Grounding, double insulated and powered by low voltage
How are bench mounted pillar drills usually powered?
Belt driven
How are floor mounted pillar drills typically driven?
Belt or chain
What are the risks when using too high of a speed for a drill bit?
Dulling cutting edges quietly & high temps
What are the risks of using too low of a cutting speed for a drill bit?
Breaking the drill bit
What does lubricant do when drilling?
Cool the bit and allows swarf to leave freely
When must a work piece not be clamped?
When it’s heavy enough to not move
How must an abrasive wheel be tested before use?
Tapped, gently with a non metallic object
What are the most commonly used power tools?
Pneumatic
What are the most common drill grips?
Pistol or straight
What is the air supply to a tool typically?
90-110psi
When are angle drills used?
Tight or limited access
What angles of angles drills are available?
30,45 & 90 degrees
What is the purpose of a drill stop?
Controls the depth of drilling
What is the purpose of a drill guide?
Keeps the drill at 90 degrees
What speed does a slow rivet gun move at?
900-2500 blows per minute
What is the purpose of a nut plate drill jig?
Accurate drilling of rivet holes
What is a blind rivet puller for?
Blind fasteners
What is the function of a rivet shaver?
Trims protruding mandrills of cherry rivets
What are the 4 types of precision measuring tools?
Vernier callipers, micrometers, dial indicators, go/no go gauge
How do you read a micrometer?
Look for the last visible line of the sleeve, then add the line on the thimble
How do you read a vernier calliper?
Look for the line closest to the movable scale. Take the valve on the left of the 0 the book for when the seals line up. Add these two value. Always look at the scale.
What are the two types of DTI?
Plunger and lever
What are DTIs used for?
Alignments of shaft and surface smoothness accuracy of 0.01 mm
What are the go/no go gauges used for?
Quickly and easily determining whether a part is within limits
What can go/no go gauges determine?
Checking seating of control cables
What does the difference between high and low represent?
The acceptable tolerance for the part
What are the 2 types of application used for greases?
Hand application or grease gun
What must accompany all lubricants?
An MSDS
What is the most common grease gun fittings?
Zerk fittings
Where are flush type fittings used?
Low clearance areas
What 2 features of the PMMC increase its accuracy?
Iron core and curved pole pieces
What are the uses of the PMMC?
DC ammeter, DC voltmeter, multi range ammeter
How do you connect the ammeter and voltmeter?
Ammeter in series
Voltmeter in parallel
When should a shunt be used?
Range of current greater than max deflection
When using a multi range ammeter what must you ensure?
Start readings at the highest range to not overload the circuit
What must you do when using an ammeter?
Disconnect aircraft power as the ammeter has its own small battery
What is the difference in the scale of a series ohm meter and a shunt?
In series 0 in the right and infinity on the left. In shunt 0 on the left and infinity on the right.
What ohmeter would you use if working in a fuel tank?
Safety ammeter as it has no battery and is powered by a hand crank, 0.5 ma
How can you measure AC on a moving coil meter?
By first rectifying it into DC
Why is it more desireable to use a full wire rectifier?
Higher sensitivity compared to half wave
What is the most common full wire rectifier?
Bridge type rectifier
What is the most common multimeter and what do they measure?
Measure AC & DC, current,voltage and resistance. Most common is AVO multimeter
What is the most common digital multimeter?
Fluke 115
What is the range of a digital multimeter?
AC+DC V to 600V , 10A (20A for 30 secs)
What are some precautions that should be taken when using a digital multimeter?
Don’t apply power to the aircraft. Disconnect system power.
What is the benefit to the use of a current clamp?
Allows for measurement without the need for physical contact
