Snips, also known as shears, are hand tools used to cut

sheet metal Sheet metal is metal formed into thin, flat pieces, usually by an industrial process. Sheet metal is one of the fundamental forms used in metalworking, and it can be cut and bent into a variety of shapes. Thicknesses can vary significantly; ex ...

and other tough webs. It is a cutting tool. Workers use various types of snips, either straight or blend one be obtained. The straight or bent being not only for straight cuts but for inside of the curvature or concave curvature too. There are two broad categories: ''tinner's snips'', which are similar to common scissors, and ''compound-action'' snips, which use a compound

lever A lever is a simple machine consisting of a beam or rigid rod pivoted at a fixed hinge, or '' fulcrum''. A lever is a rigid body capable of rotating on a point on itself. On the basis of the locations of fulcrum, load and effort, the lever is d ...

age handle system to increase the

mechanical advantage Mechanical advantage is a measure of the force amplification achieved by using a tool, mechanical device or machine system. The device trades off input forces against movement to obtain a desired amplification in the output force. The model for ...

Types

Tinner snips

Tinner's snips, also known as tinner snips or tin snips, are one of the most popular type of snips. They are defined by their long handles and short blades. They usually have extra wide jaws and are made of drop forged carbon steel. Depending on the size of the blade, tin snips can cut between 24 and 16 gauge

cold rolled In metalworking, rolling is a metal forming process in which metal stock is passed through one or more pairs of rolls to reduce the thickness, to make the thickness uniform, and/or to impart a desired mechanical property. The concept is simil ...

low-carbon

tin Tin is a chemical element with the symbol Sn (from la, stannum) and atomic number 50. Tin is a silvery-coloured metal. Tin is soft enough to be cut with little force and a bar of tin can be bent by hand with little effort. When bent, t ...

. They can be ranged in length from long. There are two main types: straight-pattern and duckbill-pattern. Straight-pattern are best for straight cuts, but can handle gentle curves. Duckbill-pattern snips, also known as trojan-pattern snips, have blades that taper down from the pivot to the tip of the blades. The blade edges are also bevelled to more easily cut curves and circles or shapes. They are a lighter duty snip that can only cut up to 25 gauge mild steel. Other common blade patterns include the circle pattern or curved pattern and the hawk's-bill pattern. Circle pattern snips have a curved blade and are used to cut circles. Hawk's-bill snips are used to cut small radii on the inside and outside of a circle. The shape of the blades allow for sharp turns without buckling the sheet metal. A common use is cutting holes in pipes.

Compound-action snips

Compound-action snips, also known as aviation snips, maille snips or sheet snips, are the most popular type of snips as they are able to exert a higher force compared to other types of snip of the same size, because of the design of their linkage. They were first developed to cut

aluminum Aluminium (aluminum in American and Canadian English) is a chemical element with the symbol Al and atomic number 13. Aluminium has a density lower than those of other common metals, at approximately one third that of steel. It ha ...

in the construction of aircraft, hence they are often referred to as ''aviation'' snips. They can handle aluminium up to 18 gauge, mild steel up to 24 gauge or stainless steel up to 26 gauge. There are three cutting styles for compound-action snips: straight cutting, left cutting, and right cutting. Straight cutting snips (generally have yellow colored soft grips) cut in a straight line and wide curves; left cutting snips (usually red) will cut straight and in a tight curve to the left; right cutting snips (usually green) will cut straight and in a tight curve to the right. These different cutting styles are necessary because metal is stiff and heavy and does not move out of the way readily when cutting around a curve. The respective styles move the material out of the way when cutting in the direction they are designed for. The blades are usually

serrated Serration is a saw-like appearance or a row of sharp or tooth-like projections. A serrated cutting edge has many small points of contact with the material being cut. By having less contact area than a smooth blade or other edge, the applied p ...

to prevent material slippage. Tin snips 4

In addition to the configurations outlined below, there are also ''upright'' and ''long cut'' configurations. The upright snip has the blades rotated 90° from the handles. This configuration is more

ergonomic Human factors and ergonomics (commonly referred to as human factors) is the application of psychological and physiological principles to the engineering and design of products, processes, and systems. Four primary goals of human factors learnin ...

and commonly used in tight spaces. The long cut snip has long blades that make it easier to make long straight cuts. These snips are commonly used on vinyl or aluminium siding. Standard compound-action snips are designed for cutting steel or softer materials, although the occasional use on stainless steel is not detrimental. For cutting through tougher materials, such as

inconel Inconel is a registered trademark of Special Metals Corporation for a family of austenitic nickel-chromium-based superalloys. Inconel alloys are oxidation-corrosion-resistant materials well suited for service in extreme environments subjected ...

and

titanium Titanium is a chemical element with the Symbol (chemistry), symbol Ti and atomic number 22. Found in nature only as an oxide, it can be reduced to produce a lustrous transition metal with a silver color, low density, and high strength, resista ...

, ''special hard'' snips are available. They are similar in design to standard or offset aviation snips but have specially

heat treat Heat treating (or heat treatment) is a group of industrial, thermal and metalworking processes used to alter the physical, and sometimes chemical, properties of a material. The most common application is metallurgical. Heat treatments are al ...

ed blades. These snips will have a different color handle to differentiate them from the other standard types.

Pipe and duct snips

Pipe and duct snips, also known as double cut snips, are a subtype of compound-action snip used to cut stove pipe and ducting lengthwise. The snips have a three-piece jaw that has two side blades that slide against a central blade. This creates a wide strip that curls up along the cut. A compound lever system is used to increase the mechanical advantage.

Configuration

The following types of snips are available in different configurations. The first is the angle of the blades to the handles. If the handles are inline with the blades then the combination is known as a straight snips; if the handles are at an angle then it is known as an offset configuration. This design allows for the material to flow away from the blades when making long cuts, which is easier and safer than straight cutting snips. The bulldog-pattern is a blade pattern that has longer handles to increase the mechanical advantage of the snips. In tinner's snips this means the handles are extra long. The compound-action bulldog-pattern, also known as a notch snips, has the ability to cut up to 16 gauge cold rolled sheet metal or multiple layers of sheet metal up to thick. Some snips have replaceable blades for when the blade becomes worn out. An added advantage to this is the ability to make the rest of the snips from a light weight material, usually aluminum. This helps to reduce fatigue.

References