ASVAB CampMetalworking Tools and Operations flashcards
8 cards with the formulas, rules and traps from this lesson. Answer in your head, then flip to check.
Rule · 1/8
Lathe versus milling machine versus drill press: what rotates?
Lathe: the workpiece rotates while a cutting tool removes material (turning, facing). Milling machine: a rotating cutter removes stock from secured work (slots, keyways, flats). Drill press: the bit rotates and feeds into stationary work.
Term · 2/8
Facing versus straight turning on a lathe?
Facing machines the end of the rotating workpiece flat and perpendicular to its axis. Straight turning reduces the outside diameter along the length of the bar.
Term · 3/8
Drilling, reaming and boring: how do they differ?
Drilling creates the initial round hole with a twist drill. Reaming removes a small amount to improve an existing hole's size and finish. Boring enlarges or refines an existing hole with a single-point cutting tool.
Term · 4/8
Ferrous versus nonferrous metals?
Ferrous metals contain iron as a principal component, such as carbon steel. Nonferrous metals include aluminum, copper, brass and bronze. A magnet test is not a reliable way to determine composition or grade.
Term · 5/8
Ductility, malleability and brittleness: what does each mean?
Ductility: can stretch a lot under tension before breaking. Malleability: can deform under compression, as when rolled into sheet. Brittleness: fractures with little plastic deformation. None of these is the same as hardness.
Formula · 6/8
Hacksaw blade TPI: what is the tooth spacing?
Spacing inch: 20 TPI gives 0.050 in, or mm. Higher TPI (finer teeth) generally suits thinner stock.
Formula · 7/8
How do diameter and RPM affect surface (cutting) speed?
, D = diameter, N = revolutions per unit time. At the same RPM, a 40 mm workpiece has twice the surface speed of a 20 mm one. Spindle speed is revolutions; cutting speed is linear speed at the edge.
Fact · 8/8
Offhand grinder work rest: what is the maximum gap to the wheel?
Under OSHA 1910.215, the work rest must be kept closely adjusted with a maximum opening of 1/8 inch (about 3.2 mm), and it is never adjusted while the wheel is turning.