CHAIN SAW

The chain saw (fig. 14- 17) is a heavy-duty pneumatic device, designed primarily for cutting trees or timbers up to 24 inches in diameter during clearing operations. The chain saw is also used to accomplish heavy timber construction, such as bridges, bunkers, and culverts.

NAIL DRIVER

The pneumatic nail driver (fig. 14-18) is a lightweight member of the reciprocating percussion family of tools and used primarily for driving large nails, spikes, and driftpins in heavy timber construction. When the nail driver is equipped with the proper attachment, it may also be used for other purposes, such as riveting, shearing heads from bolts and rivets, and removing scale and rust from metal plates or objects.

DRILL

The pneumatic drill (fig. 14-19) is a heavy-duty low-speed tool, designed to drive ship auger type of drills. The pneumatic drill is used extensively in trestle bridges and other timber construction work where it is necessary to drill holes for bolts or pins.

CIRCULAR SAW

The pneumatic circular saw (fig. 14-20) is built for heavy-duty use on timber construction work and maybe used for ripping as well as crosscut sawing. When the circular saw is equipped with the appropriate abrasive disk, designed for the specific material to be cut, it may also be used to cut brick, stone, concrete, tile, and similar materials.

SAFETY

Safety rules for pneumatic tools are as follows: . Keep your hands and fingers off the trigger or throttle until you are ready to start the tool.

. Always keep your balance.

. Never get your face close to the tool.

Figure 14-17.-Pneumatic chain saw.

Figure 14-18.-Pneumatic nail driver.

Figure 14-19.-Pneumatic drill.

Figure 14-20.-Pneumatic circular saw.

. Wear safety shoes, safety glasses or impact goggles, gloves, hearing protection, and a hard hat.

. Never rest an air tool on your toes.

. Do not allow horseplay.

. Never point an air hose at yourself or others.

. Always keep both hands on the handle of the tool while operating.

. Always bleed the airline before removing it from the tool.

CRAWLER-MOUNTED ROCK DRILL

This section provides only the basic terminology and procedures used in rock drilling operations. The extensive knowledge and skills, required to perform as an effective rock drill operator, must be gained through formal training or on-the-job-training experience.

A component of quarry operations that contains all items of equipment needed to drill is the crawlermounted rock drill (fig. 14-21). This drill is a selfpropelled unit, designed primarily to drill vertical and angular blast holes in rock.

NOTE: Consult the operator's and maintenance's manual to obtain information on the type of rock drill you are assigned.