Circular Saw and Reciprocating Saw 1999 US Air Force Civil Engineering Training

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PART 1

OUTLINES THE SAFETY PRECAUTIONS AND DESCRIBES THE REQUIRED STEPS TO PREPARE THE CIRCULAR SAW FOR OPERATION. THE OPERATIONAL PHASE ILLUSTRATES HOW TO USE THE SAW TO ACCOMPLISH A CROSSCUT, RIP CUT, POCKET CUT, AND SHEET MATERIAL CUT.

PART 2

INTRODUCES THE RECIPROCATING SAW BY IDENTIFYING THE KEY FEATURES AND CAPABILITIES. ALSO DEMONSTRATES GENERAL CUTTING PROCEDURES AND SPECIFIC APPLICATIONS SUCH AS PLUNGE CUT AND CUTTING METAL.

Originally a public domain film, slightly cropped to remove uneven edges, with the aspect ratio corrected, and one-pass brightness-contrast-color correction & mild video noise reduction applied.

The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original).

https://en.wikipedia.org/wiki/Circular_saw

Wikipedia license: http://creativecommons.org/licenses/by-sa/3.0/

A circular saw is a power-saw using a toothed or abrasive disc or blade to cut different materials using a rotary motion spinning around an arbor. A hole saw and ring saw also use a rotary motion but are different from a circular saw. Circular saws may also be loosely used for the blade itself. Circular saws were invented in the late 18th century and were in common use in sawmills in the United States by the middle of the 19th century.

A circular saw is a tool for cutting many materials such as wood, masonry, plastic, or metal and may be hand-held or mounted to a machine. In woodworking the term "circular saw" refers specifically to the hand-held type and the table saw and chop saw are other common forms of circular saws. "Skil saw" has become a generic trademark for conventional hand-held circular saws. Circular saw blades are specially designed for each particular material they are intended to cut and in cutting wood are specifically designed for making rip-cuts, cross-cuts, or a combination of both. Circular saws are commonly powered by electricity, but may be powered by a gasoline engine or a hydraulic motor which allows it to be fastened to heavy equipment, eliminating the need for a separate energy source...

In woodworking the term circular saw is most commonly used to refer to a hand-held, electric circular saw designed for cutting wood, but may be used for cutting other materials with different blades. Circular saws can be either left or right-handed, depending on the side of the blade where the motor sits. A left-handed saw is typically easier to use if held in the right hand, and contrariwise for the right-handed saw, because the user does not need to lean across the saw to see the cutting line.

Blades for cutting wood are almost universally tungsten carbide tipped (TCT), but high-speed steel (HSS) blades are also available. The saw base can be adjusted for depth of cut and can tilt up to 45° and sometimes 50° in relation to the blade. Adjusting the depth of cut helps minimize kickback. Different diameter blades are matched to each saw and are available ranging from 14 centimetres (5.5 in) to 61 centimetres (24 in).

The saw can be designed for the blade to mount directly to the motor's driveshaft known colloquially as a sidewinder, or be driven indirectly by a perpendicularly mounted motor via worm gears, garnering considerably higher torque called a worm-drive saw.

The worm-drive portable circular saw was invented in 1923 by Edmond Michel. In 1924 Michel formed a partnership with Joseph Sullivan, and together they started the Michel Electric Handsaw Company, with the sole purpose of manufacturing and marketing the saw invented by Michel. The company later renamed itself Skilsaw Inc., Portable circular saws are often still called Skilsaws or Skil saws. Its successor is still sold by Skil as the model 77. To get around the Skil patents, Art Emmons of Porter-Cable invented the direct-drive sidewinder saw in 1928. Recently smaller cordless circular saws with rechargeable batteries have become popular...

https://en.wikipedia.org/wiki/Reciprocating_saw

A reciprocating saw is a type of machine-powered saw in which the cutting action is achieved through a push-and-pull ("reciprocating") motion of the blade.

The term is commonly applied to a type of saw used in construction and demolition work. This type of saw, also known as a hognose, recip saw, or Sawzall (a trademark of the Milwaukee Electric Tool Company) has a large blade resembling that of a jigsaw and a handle oriented to allow the saw to be used comfortably on vertical surfaces. The typical design of this saw has a foot at the base of the blade, similar to that of a jigsaw. The user holds or rests this foot on the surface being cut so that the tendency of the blade to push away from or pull towards the cut as the blade travels through its movement can be countered...