7.3 Sippo Questions Flashcards
(56 cards)
When using a hacksaw how many teeth must be in contact with the metal being cut at any on time
More than 1
What technique is used to produce a good cut with a hacksaw
Start by holding the saw at an angle
Forward stroke under pressure
Return stroke without pressure
Near end before material separates reduce pressure on saw
What has to be remembered when fitting normal hacksaw blades and junior hacksaw blades
On normal - teeth must point in cutting direction
Junior - teeth facing towards handle
What prevents the hacksaw blade from binding in the material when being used
As it cuts into material the slot it created must be greater than the blade thickness. - must cut required clearance.
By:
Teeth are set
Blade is waved
What is meant by a double cut file
Has two sets of teeth overlaid at 45degrees to each other for faster material removal
Apart from double cut what are the other cuts of file
Single cut - for soft material and fine finishes
Rasp cut - wood and leather
Curved tooth - dreadnought for smooth finished on aluminium or removing large amounts of material on soft materials
What safety precautions must be observed when using files
Always use a handle on a file
Where should a bench vice be in conjunction to your body
5-8 cm below you elbow
What is the purpose of draw filling
For final finish
Usually used on parts that are relatively long
Used to get a fine surface to prevent crack growth
What is the purpose of flutes in a drill
Helical grooves provide cutting lips which permit the removal of chips and allow cutting fluid to reach the cutting lips
Where is the body of a drill bit
The part between the point and the shank. Including spiral flutes, lands and the margin
Why is it important for the body of a drill bit to be slightly tapered
Means it is fractionally larger in diameter at the tip then at the shank, therefore causing it to bore a hole with clearance to prevent the drill from binding
What type of drill best lends itself to sheet metal work
Jobber drill
How is a taper shank drill fitted to a drill motor
At the end of taper shank there is a tongue, called tang. And when taper shank is fitted into the socket spindle the tang engages in a slot
What is the drill point angle for general purpose drilling
Should be sharpened to a cone of 118 degrees (lip angle 59degrees)
What are the drill point angles for hard materials and soft materials,
Angles of 140 degrees are for hard materials
Angles of 80degrees are for soft materials
What does a pillar drill make possible
Precision drill work. As no play I’m spindle, bearing or chuck. And clamped
What are the advatange of using pneumatic drills in aviation
Less hazardous than having electrical cables on a crowded plane
Control offered by air drills. - varying trigger
What may be used to prevent a drill from penetrating too far into a structure when drilling
Drill stop
What are the three probable causes of a drill that won’t feed into the material
Drill blunt
insufficient drill cutting clearance
Drill too large (pilot hole needed)
Why does drilling of thin plate require special care
The drill point often breaks through before the drill has cut its full diameter
What clamping devices may be used when hand drilling
Angle vices, pin vices, hand vices
What is the purpose of a drill guide
The hand held drill guides keeps the drill 90 degrees to the skin surfaces.
How is a hole finder used
When replacing an old skin with a new one. If no pilot holes drilled in new skin.
The finder resembles a clamp that slips over the new skin and on its underside is a pin that exactly fits through the hole in structure. This guides the drill in making a new hole in new skin that aligns with the old one.
