7.3 Flashcards
When can you scribe something
For cut lines only
What are hammers classified by
Weight and type (with handle removed)
What should you check before using a claw hammer
That the head is set using attached to the handle
What size centre punches are there
60% for light work
90% for general indentation
What are the four types of hammers
Ball pein
Cross and Straight pien
Claw hammer
Copper and hide hammer
What are the 7 parts of a hammer
Neck
Face
Bell
Claw
Cheek
Handle
Grip
How should the teeth of a hacksaw lay
For a normal hacksaw - teeth away from you
For junior - teeth facing the handle
What is the kerf and why do we have it
The teeth are set alternately left and right to produce the kerf
Which reduces jamming as makes a clearance
What are the three types of blades we can have on a hacksaw
Coarse
Medium
Fine
When would we use a coarse hacksaw
For soft materials
When would we use a medium hacksaw
For normal general
When would we use a fine hacksaw
For hard materials/sheet metal/ cut hollows or tubing
What do you use a round file for
For small radii
What do you use a half round file for
For filling medium or large radii
What do you use a square file for
For filing keyways
What do you use to clean files
Scratch card/file brush
Or alternatively, chalk, oil or white spirit
What is the purpose of draw filling
Very fine finishes
What is the purpose of a flute of a drill bit
Allows removals of the chips/swarf
Allows cutting fluid to reach the cutting lips
When should you use an extension drill and what needs to be paired with it
Only use if absolutely necessary
Use a drill guard
What are the general angles for a drill
Inclusive angle = 118 degrees
Cutting lip = 59 degrees
What are the cutting angles for a drill bit when used on hard materials
140 degrees
70 degree cutting lip
What are the cutting angles for a drill bit when used on soft materials
80 degrees
Cutting angle 40 degrees
For a drill over 3” what needs to be limited
Speed to 6000RPM
How should you tighten a chuck
By tightening at least 2 with a chuck key
What drill sizes need a pilot
Anything above 3.2mm needs to be piloted
What does deburring prevent
Stress razors
What is a limit
The minimum and maximum permanent sizes of a component
What is a tolerance
The difference between the minimum and maximum limits
What are the three ISO system of fits
Clearance
Transition
Interference
What is the system of fits and which one is preferred
Hole basis system - preferred
Shaft basis system
What does a right hand twist reamer do
Directs the removal of the chips like a normal twist drill (swarf comes up)
What does a left hand reamer do
Twists the chips is the advance direction (down)
When should you use an expansion reamer
Only when a parallel reamer of correct size is unavailable
What are the sizes of tapered reamers for metric and imperial
Metric - 1:50
Imperial - 1:48
What size is etched on metric and imperial reamer
Metric - small diameter
Imperial - large diameter
What is the most common countersink angle
100 degrees
When do we dimple
If the sheet metal is too thin SRM will specify
What are the three taps and in what order do you tap them in
Taper
Intermediate
Bottoming/plug
What is the advantage of a bottoming/plug tap
Has no taper so can cut full thread to bottom of a blind thread
What should you thread last a tap(internal) or die (external)
Die comes last
What are the three torque wren these
Deflecting beam
Torsion bar
Toggle
What is the problem with a deflecting beam and torsion bar
Parallax error, you may read the scale wrong
What should you always do before using a torque wrentcn
Use a torque analyser to check the torque is set correctly
What is the formula when using an extension torque
Specified torque x L / L x A
What should you use if access if restricted and you cannot use a torque wrench
Pre loaded washer
What is a ratchet stop used for on a micrometer
To prevent over tightening
For metric what is one full rotation equal to on a micrometer
0.5mm
For impetial what is one full rotation equal to on a micrometer
1/40 or 0.025”
How are micrometers calibarated
By using a gauge block
