Housings are increasingly made from high-impact plastic or aluminum, which are lightweight and durable. While blades are mostly steel because of its strength and hardness, tips can be steel, carbide, diamond, or abrasive.
Power for most applications is 110- or 220-volt corded or cordless. Battery-operated saws are becoming more popular, and even 24- and 36-volt power is available for heavy-duty applications. Here are examples of the most recent advances and their impact:
Jigsaws. Higher-end jigsaws have orbital action and an adjusting knob that turns the blade for a better sawing angle without having to turn the entire saw.
Reciprocating saws. Tasks involving reciprocating saws — teardowns, for example — often require workers to cut different materials in the same cut and in close quarters. Reciprocating saws have variable-speed drives users can adjust up to 3,000 strokes per minute to give just the right speed for the material they are cutting. Also, the handle can rotate 180 degrees for the best blade-to-handle angle, and users can operate them using one hand.
Circular saws. The new generation of circular saws features: improved ergonomic handles for firmer grip with less effort; laser-cut mark alignment; arbor locks for easier blade changes; and easier access to brushes for faster checking and replacement.
Miter saws. Miter saws have new ergonomic features, such as: elastomer handles that improve grip and reduce vibration; speeds of more than 5,000 revolutions per minute for a cleaner, sharper cut; and table extenders for better material support. They have liquid-crystal displays that show bevel and miter angles, more conveniently located angle-adjustment knobs, backlighting for better visibility in dark places, and laser-cut marking adjustable to the left or right.
Concrete saws. Concrete chainsaws and blade saws have diamond-tooth tips that cut through abrasive material quickly. They can make plunge cuts and curve cuts, either wet or dry. A wall-climbing accessory supports and advances the saw while making vertical cuts in many masonry wall materials, such as poured concrete, concrete block, and brick.
Abrasive cutoff saws. The tough, abrasive saw blade, high rpm and range of power combine to produce fast, clean cuts in metal. The saw can cut a 1-inch, cold-rolled bar in 5 seconds. By comparison, this cut using a hack saw or band saw takes about a minute.
Thomas W. Westerkamp is a maintenance management consultant and CEO and managing partner of Productivity Network Innovations LLC.
Batteries: A Closer LookManagers specifying power tools must take into account the available battery technology options for tools under consideration. With increases in the number and capacity of cells in a pack, both power output and battery life have improved markedly. Lithium-ion technology is outperforming nickel-cadmium and nickel-metal hydride options. Lithium-ion cell capacity is 3 ampere-hours, compared to 2.4 for nickel-cadmium and nickel-metal hydride. Lithium-ion technology delivers twice the battery-lifetime performance, handling hundreds of recharges. It is also 25 percent lighter, improving the portability of even heavy-duty cordless saws. — Thomas A. Westerkamp |
Power Tools: The Right Saw for the Right Application
Technology Talk: Jigsaws, Miter Saws, Circular Saws
