ASVAB Auto & Shop Information Subtest: Drilling, Punching, and Gouging Tools
No, this isn’t about hand-to-hand combat training from basic training. However, the ASVAB will test your knowledge of how handy you are with drilling, punching, and gouging tools. Masters in the art of shop often make holes in the material they’re working with in order to build that perfect birdhouse (or whatever they’re working on). These holes can be made with a variety of tools.
Drills and bits
Twist drills use drill bits, which are round pieces of steel shaped in a spiral, to create holes. Drill bits are attached to a drill (usually a power drill but sometimes a hand drill operated by manually turning a crank). The point of the drill bit is sharpened, and the shank is smooth and fits into the drill.
A countersink is a drill bit that enlarges just the surface of a hole so a screw head can be accommodated. A countersink allows the top of the fastener to be set exactly even with the material to which it’s attached. Without a countersink, the fastener slightly protrudes from the material to which it’s been attached.
Auger bits bore larger holes. They’re shaped differently from drill bits. They have a long deep spiral flute for easy chip removal. They’re also much larger. Auger bits are most commonly used with a brace for drilling holes in wood. Their length varies from 7 to 10 inches.
Punches have a sharp end that’s placed against the material to be punctured; the other end is struck with a hammer. A center punch is used to mark where a drilled hole is to be placed; this keeps the drill bit in position and prevents the drill from jumping to another part of the material.
Using a Phillips screwdriver as a punch is bad form in the shop world because hitting the handle of a screwdriver with a hammer can damage it (and then you’ll get talked about in serious shop circles).
Chisels are made of steel and have a sharp cutting edge. They’re used to chip or cut metal or wood:
Metal–cutting chisels: Chisels that cut metal are usually struck with a mallet to make the cut. These chisels have different shapes depending on how they’ll be used; cold chisels are flat, and they’re used for cutting metals without using heating torches or forges, whereas round chisels make circular cuts.
Wood–cutting chisels: Some wood chisels, called socket chisels, are also struck with a mallet. Other wood chisels require only the pressure of your hands.
Wood chisels also come in different shapes, depending on what they’re used for. A butt chisel has a short blade and is used for in-close work. A mortising chisel has a narrow blade made for chiseling out the narrow mortises in joints. A framing chisel has a heavy, strong blade meant for rough work.
Because you use chisels with other tools and the pressure of your hands, there’s a little bit of a risk involved with this tool. One slip and these instruments can easily cut large chunks out of your skin, so be careful.