Theory – Hand Held Cutting Tools

What is the purpose of the second slot to hold a saw blade?
To clear the material if it’s too deep.
What is an All-Hard Saw Blade?
It is a blade that is hard throughout the entire body and will break easy if twisted.
What is a Flexible-Back Blade Saw?
A blade that is hardened only on the tooth edge, leaving the back of the blade tough so that it can stand severe strain without breaking.
How many TPI does a general purpose saw blade have?
18 Teeth per inch
How many saw blade teeth must be in contact with your work at all times to avoid breakage?
A minimum of three saw blade teeth.
What is a saw blade set? What are the two types of blade sets that can be found?
A saw blade set is the way the individual teeth or group of teeth on a saw blade are bent out of line to make sure the blade doesn’t get stuck in the material. The types of sets are Straight/Alternate and Wavy.
What is a Kerf?
The kurf is the width of the cut made by the set of a hacksaw blade.
How can you make sure you get a straight, clean start with a hacksaw?
File a V-shaped nick at your starting point.
How many strokes per minute should be done with a hacksaw?
About 50 Strokes per minute.
What should you do if your blade breaks inside of the cut?
Take out the blade and replace it with a new one, then start from the opposite side of the work or you will damage the teeth in the new blade.
What kind of file has the edge left smooth? What is it’s purpose?
It is known as a safe edge file. It allows you to avoid damaging a finished surface with the edge.
What are the 4 styles of files?
Single-cut(One set of teeth), DOUBLE-cut(Two sets of intesecting teeth), Rasp (Scalloped shaped teeth mainly for woodworking), Curve (Single cut arc teeth used for soft materials)
What are the 6 different levels of coarseness of files in order of rough to smooth?
Rough, Coarse, Bastard, SECOND-Cut, Smooth, Dead Smooth.
What is different about needle files compared to normal files?
Their handle is part of the blade instead of a wood handle.
What is another name for a Round File?
Rat Tail.
What should a file always have before you use it?
A handle, otherwise it can be driven into the palm of your hand with enough force. Ouch!
How much pressure should you use when cross filing?
Use a medium amount of pressure on the forward stroke and very little on the return.
What is cross filing? What kind of file should you use?
Filing from the heel of the file to the Point, used to remove large amounts of material. Use a double-cut bastard file.
What is draw filing? What kind of file should you use?
Holding the blade in both hands on top of your work and moving the file back and forth along the length. It is used to produce a good surface finish. Use a smooth single cut file.
What do you use to clean a file? What are you removing in the process?
You should use a file CARD to clean the blade and remove pinning. You can also used a soft piece of metal across the blade to remove harder to remove pins.
Is a file a pry bar?
NO
How should you use a file in a lathe?
When filing in the lathe use a low speed and hold the file in your left hand to keep your body away from the chuck.
What are the three types of Scrapers?
Flat, Triangular(Three Cornered), Bearing Scraper(Spoon)
What are the four types of Chisels?
Flat(Cold), Cape, Round Nose, Diamond Point
What is the included angle of a Flat/Cold Chisel?
60 Degrees
What is the purpose of a Cape Chisel?
To cut key seats in shafts.
What is the purpose of a Round Nose Chisel?
To cut oil grooves.
What is the purpose of a Diamond Point Chisel?
Squaring 90 degree angles of keyseats
Your chisel has a mushroom head, what should you do?
Grind away the mushroomed portion, it may need hardening and possibly re-tempering if it has softened.
What degree should you grind a chisel to for cutting steel?
60 Degrees
What is the formula for Tap Drill Size?
TDS = D – 1/N or TDS = D – P
What is the formula to find the Tap Drill Size for numbered machine screws.
OD = # x 0.013 – 0.060
What are the three types of taps used to thread a hole?
Taper, Plug and Bottoming.
What is a Spiral Pointed/Gun Tap?
A tap that pushes chips ahead.
What is a Spiral Fluted Tap?
A tap that pulls the chips out the back of the hole.
What is a Fluteless Tap?
A tap that forms threads and doesn’t cut. Just pushes material into shape. Used in plastics etc.
What is a Pipe Tap?
They can be tapered and straight and only go in about half way down the tap.
What makes Serial Taps different from regular Taps?
They have rings around the shank to identify the tap and get progressively bigger from the first(Taper Tap) to the third(Bottoming Tap). They are used for materials that are harder to tap.
What should you do to a hole before tapping?
Countersink the hole so it is slightly larger than the diameter of the thread.
What is EDM in relation to taps?
It is the process of disintegrating the metal using electrical discharge. It is known as Electrical discharge machining.
What is the process of Upsetting a bold or stud?
It is the process of heating up a bolt inside of a hole making it expand against the hole, since it can’t become wider it thins out deeper in the hole making it easier to extract.
How is a die turned?
Using the diestock.
What is the purpose of an adjustable split die?
To obtain different classes of thread fits. (looser and tighter)
How much smaller should the diameter of a workpiece be before threading?
0.002″ to 0.010″ undersized
What is a solid die or die nut used for?
They are used to chase and recondition damaged threads.
How do you know if a reamer is meant for hand use?
It has a square end.
How much smaller should a hole be before reaming it by hand?
The hole should be .005″ undersized for holes smaller than half an inch up to a maximum of 0.010″ undersized for holes larger than half an inch.
What is the taper of a Taper Pin Reamer?
1/4″ per foot
What is the length of a taper equal to on a reamer in comparison to the rest of the tool?
It is equal to the diameter of the reamer.
What is the advantage of a Helical fluted reamer?
It can bore into a hole without worry of the flute catching in a groove or keyway.
What are diagonal pliers used for?
Cutting music wire and light metal
What is the compound called that is used to produce an extremely smooth and accurate surface. What is the compound used on?
The compound is called Lapping Paste. It is typically used on a cast iron plate that has a diamond patterned groove to flush out particles.
The three (3) hand taps found in a set are the:
a) starter, plug and bottoming.
b) taper, plug and bottoming.
c) taper, intermediate and finishing.
d) starter, intermediate and chamfered.
b) The three hand taps found in a set are the Taper, plug and bottoming.
If a high-speed steel hand tap breaks in a hole, one way to remove it would be:
a) with an electrical discharge machine.
b) by drilling it out with a high-speed steel drill bit.
c) by drilling a hole and using a stud extractor
d) with a tap vibrator
a) If a high-speed steel hand tap breaks in a hole, one way to remove it would be with an electronic discharge machine (EDM)
Serial taps of the same nominal size:
a) have different pitch diameters
b) have the same pitch diameter
c) are used in mass production
d) can be used in any sequence.
a) Serial taps of the same nominal size have different pitch diameters.
A die is turned with a:
a) die wrench
b) die stock
c) die plate
d) die handle
b) A die is turned with a die stock
The purpose of draw filing is to:
a) remove metal rapidly
b) produce a smooth, flat surface
c) finish rough surfaces
d) remove sharp corners and burs
b) The purpose of draw filing is to produce a smooth, flat surface
The most suitable chisel for cutting oil grooves is the:
a) cold chisel
b) flat chisel
c) round nose chisel
d) diamond point chisel
c) The most suitable chisel for cutting oil grooves is the round nose chisel
An all-hard hacksaw blade would be best suited used on:
a) steel tubing
b) copper tubing
c) large brass sections
d) angle iron
c) An all-hard hacksaw blade would be best suited used on large brass sections
The length of a taper on the end of a hand reamer:
a) is approximately the same size as the tang
b) is equal to the helix angle
c) is always one inch
d) is approximately equal to the diameter
d) is approximately equal to the diameter
The cutting action of a hand broach is performed by a series of successive teeth, each protruding:
a) 0.001 inch further than the preceding tooth
b) 0.002 inch further than the preceding tooth
c) 0.0003 inch further than the preceding tooth
d) 0.003 inch further than the preceding tooth.
d) 0.003 inch further than the preceding tooth.

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