Swarf, also known as chips or by other process-specific names (such as turnings, filings, or shavings), are pieces of metal, wood, or plastic that are the debris or waste resulting from

machining Machining is a process in which a material (often metal) is cut to a desired final shape and size by a controlled material-removal process. The processes that have this common theme are collectively called subtractive manufacturing, which utilizes ...

woodworking Woodworking is the skill of making items from wood, and includes cabinet making (cabinetry and furniture), wood carving, woodworking joints, joinery, carpentry, and woodturning. History Along with Rock (geology), stone, clay and animal parts, ...

, or similar subtractive (material-removing) manufacturing processes. Swarf or chips can be small particles (such as the gritty swarf from

grinding Grind is the cross-sectional shape of a blade. Grind, grinds, or grinding may also refer to: Grinding action * Grinding (abrasive cutting), a method of crafting * Grinding (dance), suggestive club dancing * Grinding (video gaming), repetitive and ...

metal or the

sawdust Sawdust (or wood dust) is a by-product or waste product of woodworking operations such as sawing, sanding, milling, planing, and routing. It is composed of small chippings of wood. These operations can be performed by woodworking machinery, ...

from sawing or

sanding upright=1.35, Sheets of sandpaper with different grit sizes (40 (coarse), 80, 150, 240, 600 (fine)). Sandpaper and glasspaper are names used for a type of coated abrasive that consists of sheets of paper or cloth with abrasive material glued to ...

wood); long, stringy tendrils (such as the springy chips from

turning Turning is a machining process in which a cutting tool, typically a non-rotary tool bit, describes a helix toolpath by moving more or less linearly while the workpiece rotates. Usually the term "turning" is reserved for the generation of ...

tough metals, or long shavings from

whittling Whittling may refer either to the art of carving shapes out of raw wood using a knife or a time-occupying, non-artistic (contrast wood carving for artistic process) process of repeatedly shaving slivers from a piece of wood. It is used by many as ...

);

slag Slag is a by-product of smelting (pyrometallurgical) ores and used metals. Broadly, it can be classified as ferrous (by-products of processing iron and steel), ferroalloy (by-product of ferroalloy production) or non-ferrous/base metals (by-prod ...

-like waste (such as is produced within pipe during pipefitting work); or

stone In geology, rock (or stone) is any naturally occurring solid mass or aggregate of minerals or mineraloid matter. It is categorized by the minerals included, its Chemical compound, chemical composition, and the way in which it is formed. Rocks ...

fragments and dust (as in

masonry Masonry is the building of structures from individual units, which are often laid in and bound together by mortar; the term ''masonry'' can also refer to the units themselves. The common materials of masonry construction are bricks, building ...

)."The universe is finished; the copestone is on, and the chips were carted off a million years ago." —Ishmael, in ''

Moby-Dick ''Moby-Dick; or, The Whale'' is an 1851 novel by American writer Herman Melville. The book is the sailor Ishmael (Moby-Dick), Ishmael's narrative of the obsessive quest of Captain Ahab, Ahab, captain of the whaler, whaling ship ''Pequod (Moby- ...

'', by Herman Melville. Some of these terms are

mass noun In linguistics, a mass noun, uncountable noun, non-count noun, uncount noun, or just uncountable, is a noun with the syntactic property that any quantity of it is treated as an undifferentiated unit, rather than as something with discrete elemen ...

s (such as ''swarf'' and ''sawdust'') and some of them are

count noun In linguistics, a count noun (also countable noun) is a noun that can be modified by a quantity and that occurs in both singular and plural forms, and that can co-occur with quantificational determiners like ''every'', ''each'', ''several'', et ...

s (such as ''chips'', ''filings'', or ''shavings''). Wood swarf is discussed at ''

''.

Metal swarf

Chips can be extremely sharp and they can cause serious

injuries An injury is any physiological damage to living tissue caused by immediate physical stress. An injury can occur intentionally or unintentionally and may be caused by blunt trauma, penetrating trauma, burning, toxic exposure, asphyxiation, or ...

if not handled correctly. It is not uncommon for chips flying off the cutter to be ejected with great force and to fly several yards. Due to its high

surface area The surface area of a solid object is a measure of the total area that the surface of the object occupies. The mathematical definition of surface area in the presence of curved surfaces is considerably more involved than the definition of arc ...

, swarf composed of some reactive metals can be highly flammable. Swarf may also spontaneously combust, especially if the swarf is coated with cutting oil. To extinguish swarf fires, a special

fire extinguisher A fire extinguisher is a handheld active fire protection device usually filled with a dry or wet chemical used to extinguish or control small fires, often in emergencies. It is not intended for use on an out-of-control fire, such as one which ha ...

is needed, designed for fighting Class D (metal) fires. When machining without coolant, swarf is usually very hot and can easily burn the machine operator. Machinists typically wear long pants, eye protection and other personal protective equipment for this reason. Some common engineering materials such as

beryllium Beryllium is a chemical element with the symbol Be and atomic number 4. It is a steel-gray, strong, lightweight and brittle alkaline earth metal. It is a divalent element that occurs naturally only in combination with other elements to form mi ...

are hazardous when finely divided and appropriate measures should be taken to prevent exposure. For ease of transport and handling, swarf may be compressed into ''bricks''. Metal swarf can usually be

recycled Recycling is the process of converting waste materials into new materials and objects. The recovery of energy from waste materials is often included in this concept. The recyclability of a material depends on its ability to reacquire the p ...

References

{{Authority control Machining Metalworking terminology