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141-424: The screw head on one end has a milled slot that commonly requires a tool to transfer the twisting force. Common tools for driving screws include screwdrivers , wrenches , coins and hex keys . The head is usually larger than the body, which provides a bearing surface and keeps the screw from being driven deeper than its length; an exception being the set screw (aka grub screw ). The cylindrical portion of

282-404: A mill by machinists . The archaic term miller was commonly used in the 19th and early 20th centuries. Since the 1960s there has developed an overlap of usage between the terms milling machine and machining center . NC/ CNC machining centers evolved from milling machines, which is why the terminology evolved gradually with considerable overlap that still persists. The distinction, when one

423-406: A built-in rotary table that allows milling at various angles; this feature is called a universal table . While endmills and the other types of tools available to a vertical mill may be used in a horizontal mill, their real advantage lies in arbor-mounted cutters, called side and face mills, which have a cross section rather like a circular saw, but are generally wider and smaller in diameter. Because

564-587: A commodity, that same object has a different value: the amount for which it can be exchanged for another commodity. According to Marx, this new value of the commodity is derived from the time taken to produce the good, and other considerations are obsolete, including morality, environmental impact, and aesthetic appeal. Marx claimed that everything would eventually be commodified: "the things which until then had been communicated, but never exchanged, given, but never sold, acquired, but never bought – virtue, love, conscience – all at last enter into commerce." Media, as

705-486: A conversational style, a seemingly real experience by a real person, allowing users connect to the blogger as a friendly voice offering advice on travel choices. A critique of elites in modern societies using media to select aspects of a local culture, repackage and redistribute the alternate view of that culture for profit. Current research include books by: S. Jhally, H.M. Enzensberger, S. Gunster and J. Tunstall. Controversy and disruption occurs when this alternate view

846-400: A culture industry , is apparent from the rise of mass communications to monetize a populace for profit. Research in critical cultural studies of media effects identify, commodification of culture, as a recent large contributing force for disruption of a society by mass media. An example is the display of American culture, to the population within its borders, and abroad. The commodity being sold

987-413: A distinct class of machine tool (separate from lathes running rotary files) first appeared between 1814 and 1818. The centers of earliest development of true milling machines were two federal armories of the U.S. ( Springfield and Harpers Ferry ) together with the various private armories and inside contractors that shared turnover of skilled workmen with them. Between 1912 and 1916, Joseph W. Roe ,

1128-449: A finish end mill. Most of the industrial milling operations can be taken care of by 2.5 axis CNC milling. This type of path control can machine up to 80% of all mechanical parts. Since the importance of pocket milling is very relevant, therefore effective pocketing approaches can result in reduction in machining time and cost. NC pocket milling can be carried out mainly by two tool paths, viz., linear and non-linear. In this approach,

1269-465: A fixed elevation; the Z-axis is controlled by moving the head or quill down toward the X,Y table. A mill drill typically has an internal taper fitting in the quill to take a collet chuck, face mills, or a Jacobs chuck similar to the vertical mill. A horizontal mill has the same short but the cutters are mounted on a horizontal spindle, or arbor, mounted across the table. Many horizontal mills also feature

1410-609: A further example of self-commodification. Human commodity is a term used in case of human organ trade , paid surrogacy (also known as commodification of the womb ), and human trafficking . According to Gøsta Esping-Andersen , people are commodified or 'turned into objects' when selling their labour on the market to an employer. Personal information through Social Networking Sites ( SNS's ), such as music purchases, how we identify, and user profiles are aggregated and sold to corporations and businesses for micro targeting, advertising and marketing. Social Media Influencers are also

1551-508: A geared head or electronic speed control. They generally have quite heavy-duty spindle bearings to deal with the lateral loading on the spindle that is created by a milling operation. A mill drill also typically raises and lowers the entire head, including motor, often on a dovetailed (sometimes round with rack and pinion) vertical column. A mill drill also has a large quill that is generally locked during milling operations and released to facilitate drilling functions. Other differences that separate

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1692-573: A greater plurality of formerly competing standards exist. Newer and larger manual machines usually use NMTB tooling. This tooling is somewhat similar to CAT tooling but requires a drawbar within the milling machine. Furthermore, there are a number of variations with NMTB tooling that make interchangeability troublesome. The older a machine, the greater the plurality of standards that may apply (e.g., Morse , Jarno , Brown & Sharpe , Van Norman , and other less common builder-specific tapers). However, two standards that have seen especially wide usage are

1833-492: A hard and temperature-resistant material, so that they wear slowly. A low cost cutter may have surfaces made of high speed steel . More expensive but slower-wearing materials include cemented carbide . Thin film coatings may be applied to decrease friction or further increase hardness. There are cutting tools typically used in milling machines or machining centers to perform milling operations (and occasionally in other machine tools). They remove material by their movement within

1974-439: A lighter, more versatile machine, called a mill-drill. The mill-drill is a close relative of the vertical mill and quite popular in light industry; and with hobbyists. A mill-drill is similar in basic configuration to a very heavy drill press, but equipped with an X-Y table and a much larger column. They also typically use more powerful motors than a comparably sized drill press, most are muti-speed belt driven with some models having

2115-428: A low yield of parts because the machines single blade would cause loss of gear teeth when the cutter hit parallel grains in the wood. Terry later invented a spindle cutting machine to mass produce parts in 1807. Other Connecticut clockmakers like James Harrison of Waterbury, Thomas Barnes of Litchfield, and Gideon Roberts of Bristol, also used milling machines to produce their clocks. It is clear that milling machines as

2256-508: A major focus on entertainment, loss of childhood, cultivation, and a disruptions of social conventions. Commodification of animals is one of the earliest forms of commodification, which can be traced back to the time when domestication of animals began. It includes animal slavery in all forms, including use of animals for food , medicine , fashion and cosmetics , medical research , labor and transport , entertainment , wildlife trade , companionship , and so forth. Scholars say that

2397-452: A mill-drill from a drill press may be a fine tuning adjustment for the Z-axis, a more precise depth stop, the capability to lock the X, Y or Z axis, and often a system of tilting the head or the entire vertical column and powerhead assembly to allow angled cutting-drilling. Aside from size, the principal difference between these lighter machines and larger vertical mills is that the X-Y table is at

2538-471: A modern twist. According to Mariana Torgovnick: What is clear now is that the West's fascination with the primitive has to do with its own crises in identity, with its own need to clearly demarcate subject and object even while flirting with other ways of experiencing the universe. hooks states that marginalized groups are seduced by this concept because of "the promise of recognition and reconciliation". When

2679-469: A nearby forge. The screw mill was not a commercial success; it eventually failed due to competition from the lower-cost, gimlet-pointed screw, and ceased operations in 1836. The American development of the turret lathe (1840s) and of automatic screw machines derived from it (1870s) drastically reduced the unit cost of threaded fasteners by increasingly automating the machine-tool control. This cost reduction spurred ever greater use of screws. Throughout

2820-415: A non-commercial good has become commercial, typically with connotations of "corrupted by commerce", while commoditization is used in business contexts to mean when the market for an existing product has become a commodity market, where products are interchangeable and there is heavy price competition. In a quip: "Microprocessors are commoditized. Love is commodified." The Marxist understanding of commodity

2961-423: A nut. Sheet-metal screws do not have the chip-clearing flute of self-tapping screws. However, some wholesale vendors do not distinguish between the two kinds. A wood screw is a metal screw used to fix wood, with a sharp point and a tapered thread designed to cut its own thread into the wood. Some screws are driven into intact wood; larger screws are usually driven into a hole narrower than the screw thread, and cut

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3102-572: A recent examples of self-commodification. A travel blogger is an instance of a mediated micro-celebrity, the social-media influencer, targeting a niche audience interested in visiting exotic locale. Social Media networks expand the reach of this focused audience to make influencing a profitable profession. They commodify themselves by offering online journals, advice, thoughts, experiences along with photographs and videos, then make money by, selling books, self-branding, blog subscriptions, and advertorials. Trust and an increased audience are built by expressing

3243-409: A respected founding father of machine tool historians, credited Eli Whitney (one of the private arms makers mentioned above) with producing the first true milling machine. By 1918, he considered it "Probably the first milling machine ever built—certainly the oldest now in existence […]." However, subsequent scholars, including Robert S. Woodbury and others, have improved upon Roe's early version of

3384-501: A right-hand screw. For this reason, the left-side pedal of a bicycle has a left-hand thread . The screw mechanism is one of the six classical simple machines defined by Renaissance scientists. Fasteners had become widespread involving concepts such as dowels and pins, wedging, mortises and tenons , dovetails , nailing (with or without clenching the nail ends), forge welding , and many kinds of binding with cord made of leather or fiber, using many kinds of knots . The screw

3525-512: A slot, a flat surface, and an angular groove , a good method to cut these (within a non- CNC context) would be gang milling. All the completed workpieces would be the same, and milling time per piece would be minimized. Gang milling was especially important before the CNC era, because for duplicate part production, it was a substantial efficiency improvement over manual-milling one feature at an operation, then changing machines (or changing setup of

3666-637: A standard (in about 1841) was the English engineer Sir Joseph Whitworth . Whitworth screw sizes are still used, both for repairing old machinery and where a coarser thread than the metric fastener thread is required. Whitworth became British Standard Whitworth , abbreviated to BSW (BS 84:1956) and the British Standard Fine (BSF) thread was introduced in 1908 because the Whitworth thread was too coarse for some applications. The thread angle

3807-433: A substrate, and most are classed as screws. Mating threads are formed in the substrate as these fasteners are driven in. Fasteners with a non-tapered shank are generally designed to mate with a nut or to be driven into a tapped hole, and most would be classed as bolts , although some are thread-forming (eg. taptite ) and some authorities would treat some as screws when they are used with a female threaded fastener other than

3948-420: A system to retract those parts not in use. The choice between vertical and horizontal spindle orientation in milling machine design usually hinges on the shape and size of a workpiece and the number of sides of the workpiece that require machining. Work in which the spindle's axial movement is normal to one plane, with an endmill as the cutter, lends itself to a vertical mill, where the operator can stand before

4089-401: A two-axis turret enabling the spindle to be pointed in any direction on desires. The two options may be driven independently or from one motor through gearing. In either case, as the work is generally placed in the same place for either type of operation, the mechanism for the method not being used is moved out of the way. In smaller machines, "spares" may be lifted off while larger machines offer

4230-456: A variety of screw head shapes. A few varieties of screw are manufactured with a break-away head, which snaps off when adequate torque is applied, to prevent removal after fitting, often to avoid tampering. The international standards for metric externally threaded fasteners are ISO 898-1 for property classes produced from carbon steels and ISO 3506-1 for property classes produced from corrosion resistant steels. There are many standards governing

4371-440: A very high production rate, and produces virtually no waste material. Slotted head screws require an extra step to cut the slot in the head; this is done on a slotting machine . These machines are essentially stripped down milling machines designed to process as many blanks as possible. The blanks are then polished again prior to threading. The threads are usually produced via thread rolling ; however, some are cut . The workpiece

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4512-445: A wide variety of different operations and machines, on scales from small individual parts to large, heavy-duty gang milling operations. It is one of the most commonly used processes for machining custom parts to precise tolerances. Milling can be done with a wide range of machine tools . The original class of machine tools for milling was the milling machine (often called a mill). After the advent of computer numerical control (CNC) in

4653-455: Is 0.25–3 in (6.35–76.20 mm) in diameter . In 1991, responding to an influx of counterfeit fasteners, Congress passed PL 101-592, the "Fastener Quality Act". As a result, the ASME B18 committee re-wrote B18.2.1, renaming finished hex bolts to hex cap screw  – a term that had existed in common usage long before, but was now also being codified as an official name for

4794-491: Is 1/4" Whitworth (20 tpi) and for medium/large format cameras is 3/8" Whitworth (16 tpi). It is also used for microphone stands and their appropriate clips, again in both sizes, along with "thread adapters" to allow the smaller size to attach to items requiring the larger thread. Note that while 1/4" UNC bolts fit 1/4" BSW camera tripod bushes, yield strength is reduced by the different thread angles of 60° and 55° respectively. British Association (BA) screw threads, named after

4935-485: Is 400 MPa ultimate strength and 0.6*400=240 MPa yield strength. High-strength steel bolts have property class 8.8, which is 800 MPa ultimate strength and 0.8*800=640 MPa yield strength or above. Milling (machining) Milling is the process of machining using rotary cutters to remove material by advancing a cutter into a workpiece . This may be done by varying directions on one or several axes, cutter head speed, and pressure. Milling covers

5076-413: Is America, but mediated to show only the most exciting, dramatic, attention-getting, emotion-rousing aspects. Media corporations are expert at analyzing, selecting interesting, appealing bits and pieces of the culture, repackaging and enhancing content for a wide audience. The quest for large viewership creates an image that does not show boring, unpleasant, or minority aspects of America. The distribution of

5217-408: Is a misnomer ) or French wood screw (Scandinavia) are large wood screws. Lag screws are used to lag together lumber framing, to lag machinery feet to wood floors, and for other heavy carpentry applications. The attributive modifier lag came from an early principal use of such fasteners: the fastening of lags such as barrel staves and other similar parts. These fasteners are "screws" according to

5358-712: Is a spanner (UK usage) or wrench (US usage), while a nut setter is used with a power screw driver. Modern screws employ a wide variety of screw drive designs , each requiring a different kind of tool to drive in or extract them. The most common screw drives are the slotted and Phillips in the US; hex, Robertson, and Torx are also common in some applications, and Pozidriv has almost completely replaced Phillips in Europe. Some types of drive are intended for automatic assembly in mass-production of such items as automobiles. More exotic screw drive types may be used in situations where tampering

5499-449: Is a closed loop system and functions on feedback. These machines have developed from the basic NC (NUMERIC CONTROL) machines. A computerized form of NC machines is known as CNC machines. A set of instructions (called a program) is used to guide the machine for desired operations. There are over 100 different G-codes and M-codes. Some very commonly used codes, which are used in the program are: Various other codes are also used. A CNC machine

5640-471: Is a high degree of standardization of the tooling used with CNC milling machines, and a lesser degree with manual milling machines. To ease up the organization of the tooling in CNC production many companies use a tool management solution. Milling cutters for specific applications are held in various tooling configurations. CNC milling machines nearly always use SK (or ISO), CAT, BT or HSK tooling. SK tooling

5781-420: Is also easier to cut gears on a horizontal mill. Some horizontal milling machines are equipped with a power-take-off provision on the table. This allows the table feed to be synchronized to a rotary fixture, enabling the milling of spiral features such as hypoid gears. A universal milling machine is one with the facility to either have a horizontal spindle or a vertical spindle. The latter sometimes being on

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5922-423: Is better. In this approach, tool movement is multi-directional. One example of non-linear tool path is contour-parallel tool path. In this approach, the required pocket boundary is used to derive the tool path. In this case, the cutter is always in contact with the work material. Hence the idle time spent in positioning and retracting the tool is avoided. For large-scale material removal, contour-parallel tool path

6063-399: Is called a screwdriver . A power tool that does the same job is a power screwdriver ; power drills may also be used with screw-driving attachments. Where the holding power of the screwed joint is critical, torque-measuring and torque-limiting screwdrivers are used to ensure sufficient but not excessive force is developed by the screw. The hand tool for driving hex head threaded fasteners

6204-449: Is distinct from its meaning in business. Commodity played a key role throughout Karl Marx 's work; he considered it a cell-form of capitalism and a key starting point for an analysis of this politico-economic system. Marx extensively criticized the social impact of commodification under the name commodity fetishism and alienation . Prior to being turned into a commodity, an object has a "specific individual use value". After becoming

6345-476: Is in the United States. It is claimed that HSK tooling is even better than BT Tooling at high speeds. The holding mechanism for HSK tooling is placed within the (hollow) body of the tool and, as spindle speed increases, it expands, gripping the tool more tightly with increasing spindle speed. There is no pull stud with this type of tooling. For manual milling machines, there is less standardization, because

6486-469: Is made, is that a machining center is a mill with features that pre- CNC mills never had, especially an automatic tool changer (ATC) that includes a tool magazine (carousel), and sometimes an automatic pallet changer (APC). In typical usage, all machining centers are mills, but not all mills are machining centers; only mills with ATCs are machining centers. Most CNC milling machines (also called machining centers ) are computer controlled vertical mills with

6627-413: Is operated by a single operator called a programmer. This machine is capable of performing various operations automatically and economically. With the declining price of computers and open source CNC software , the entry price of CNC machines has plummeted. The accessories and cutting tools used on machine tools (including milling machines) are referred to in aggregate by the mass noun "tooling". There

6768-430: Is pushed off the work piece in tiny clumps that hang together to a greater or lesser extent (depending on the material) to form chips. This makes metal cutting somewhat different (in its mechanics ) from slicing softer materials with a blade . The milling process removes material by performing many separate, small cuts. This is accomplished by using a cutter with many teeth, spinning the cutter at high speed, or advancing

6909-505: Is seen as untruthful to the culture that is depicted. Disruptions include misconceptions, sameness, and a focus on entertainment. Many holidays such as Christmas , Halloween or Valentine's Day have been argued as having become commodified. The commodification of a holiday refers to making celebrations necessarily commercial and based on material goods, like gift giving, elaborate decorations, trick or treating, and card giving. Modern celebrations of many holidays are now more related to

7050-590: Is successful at spreading American culture worldwide. Critical cultural research reveal consequences for the lifting of bits of culture, remolding for a mass audience, then selling the alternate view. A few of repercussions of commodification of culture: Only selected, majority cultural practices are shown leaving out other important minority cultures which are overlooked and/or ignored. As in Hollywood movies, only selected most exciting, dramatic, emotional aspects are presented while removing unpleasant, controversial or

7191-537: Is the most common in Europe, while CAT tooling, sometimes called V-Flange Tooling, is the oldest and probably most common type in the USA. CAT tooling was invented by Caterpillar Inc. of Peoria, Illinois , in order to standardize the tooling used on their machinery. CAT tooling comes in a range of sizes designated as CAT-30, CAT-40, CAT-50, etc. The number refers to the Association for Manufacturing Technology (formerly

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7332-620: Is the outer diameter of the thread. The tapped hole (or nut) into which the screw fits, has an internal diameter which is the size of the screw minus the pitch of the thread. Thus, an M6 screw, which has a pitch of 1 mm, is made by threading a 6 mm shank, and the nut or threaded hole is made by tapping threads into a hole of 5 mm diameter (6 mm − 1 mm). Metric hexagon bolts, screws and nuts are specified, for example, in International Standards ISO 4014, ISO 4017, and ISO 4032. The following table lists

7473-423: Is the tensile stress at which the bolt fails. Tensile yield strength is the stress at which the bolt will yield in tension across the entire section of the bolt and receive a permanent set (an elongation from which it will not recover when the force is removed) of 0.2% offset strain . Proof strength is the usable strength of the fastener. Tension testing of a bolt up to the proof load should not cause permanent set of

7614-406: Is the thread used to hold the pull stud. CAT Tooling is all Imperial thread and BT Tooling is all Metric thread. Note that this affects the pull stud only; it does not affect the tool that they can hold. Both types of tooling are sold to accept both Imperial and metric sized tools. SK and HSK tooling, sometimes called "Hollow Shank Tooling", is much more common in Europe where it was invented than it

7755-400: Is then cold headed , which is a cold working process. Heading produces the head of the screw. The shape of the die in the machine dictates what features are pressed into the screw head; for example a flat head screw uses a flat die. For more complicated shapes two heading processes are required to get all of the features into the screw head. This production method is used because heading has

7896-414: Is then tumble finished with wood and leather media to do final cleaning and polishing. For most screws, a coating, such as electroplating with zinc ( galvanizing ) or applying black oxide , is applied to prevent corrosion. Threaded fasteners either have a tapered shank or a non-tapered shank. Fasteners with tapered shanks are designed to either be driven into a substrate directly or into a pilot hole in

8037-651: Is undesirable, such as in electronic appliances that should not be serviced by the home repair person. There are many systems for specifying the dimensions of screws, but in much of the world the ISO metric screw thread preferred series has displaced the many older systems. Other relatively common systems include the British Standard Whitworth , BA system (British Association) , and the Unified Thread Standard . The basic principles of

8178-507: Is usually a smaller fastener (less than 1 ⁄ 4 inch (6.35 mm) in diameter) threaded the entire length of its shank that usually has a recessed drive type (slotted, Phillips, etc.), usually intended to screw into a pre-formed thread, either a nut or a threaded (tapped) hole, unlike a wood or self-tapping screw. Machine screws are also made with socket heads (see above), often referred to as socket-head machine screws. ASME standard B18.2.1-1996 specifies hex cap screws whose size range

8319-433: Is well known. In 1783, Samuel Rehe invented a true milling machine. In 1795, Eli Terry began using a milling machine at Plymouth Connecticut in the production of tall case clocks. With the use of his milling machine, Terry was the first to accomplish Interchangeable parts in the clock industry. Milling wooden parts was efficient in interchangeable parts, but inefficient in high yields. Milling wooden blanks results in

8460-400: Is widely used because it can be consistently used with up-cut or down-cut method during the entire process. There are three different approaches that fall into the category of contour-parallel tool path generation. They are: In this approach, the tool travels along a gradually evolving spiral path. The spiral starts at the center of the pocket to be machined and the tool gradually moves towards

8601-825: The Machinery's Handbook criteria, and the obsolescent term "lag bolt" has been replaced by "lag screw" in the Handbook . However, based on tradition many tradesmen continue to refer to them as "bolts", because, like head bolts, they are large, with hex or square heads that require a wrench, socket, or specialized bit to turn. The head is typically an external hex. Metric hex-headed lag screws are covered by DIN 571. Inch square-headed and hex-headed lag screws are covered by ASME B18.2.1. A typical lag screw can range in diameter from 4 to 20 mm or #10 to 1.25 in (4.83 to 31.75 mm), and lengths from 16 to 200 mm or 1 ⁄ 4 to 6 in (6.35 to 152.40 mm) or longer, with

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8742-515: The United States , but is also extensively used in Canada and occasionally in other countries. The size of a UTS screw is described using the following format: X-Y , where X is the nominal size (the hole or slot size in standard manufacturing practice through which the shank of the screw can easily be pushed) and Y is the threads per inch (TPI). For sizes 1 ⁄ 4 inch and larger

8883-411: The industrial revolution . They are key components of micrometers and lathes. There are three steps in manufacturing a screw: heading , thread rolling , and coating . Screws are normally made from wire , which is supplied in large coils, or round bar stock for larger screws. The wire or rod is then cut to the proper length for the type of screw being made; this workpiece is known as a blank . It

9024-440: The screwdriver is in the medieval Housebook of Wolfegg Castle , a manuscript written sometime between 1475 and 1490. However they probably did not become widespread until after 1800, once threaded fasteners had become commodified. Metal screws used as fasteners were rare in Europe before the 15th century, if known at all. The metal screw did not become a common fastener until machine tools for mass production developed toward

9165-405: The 1950s and 1960s. He quotes Battison as concluding that "There is no evidence that Whitney developed or used a true milling machine." Baida says, "The so-called Whitney machine of 1818 seems actually to have been made after Whitney's death in 1825." Baida cites Battison's suggestion that the first true milling machine was made not by Whitney, but by Robert Johnson of Middletown. The late teens of

9306-429: The 1960s, milling machines evolved into machining centers : milling machines augmented by automatic tool changers, tool magazines or carousels, CNC capability, coolant systems, and enclosures. Milling centers are generally classified as vertical machining centers (VMCs) or horizontal machining centers (HMCs). The integration of milling into turning environments, and vice versa, began with live tooling for lathes and

9447-406: The 19th century were a pivotal time in the history of machine tools, as the period of 1814 to 1818 is also the period during which several contemporary pioneers ( Fox , Murray , and Roberts ) were developing the planer , and as with the milling machine, the work being done in various shops was undocumented for various reasons (partially because of proprietary secrecy, and also simply because no one

9588-409: The 19th century, the most commonly used forms of screw head (that is, drive types ) were simple internal-wrenching straight slots and external-wrenching squares and hexagons. These were easy to machine and served most applications adequately. Rybczynski describes a flurry of patents for alternative drive types in the 1860s through 1890s, but explains that these were patented but not manufactured due to

9729-460: The ASME B18 standard. Lug bolt and head bolts are other terms that refer to fasteners that are designed to be threaded into a tapped hole that is in part of the assembly and so based on the Machinery's Handbook distinction they would be screws. Here common terms are at variance with Machinery's Handbook distinction. Lag screws (US) or coach screws (UK, Australia, and New Zealand) (also referred to as lag bolts or coach bolts , although this

9870-685: The British Association for Advancement of Science, were devised in 1884 and standardised in 1903. Screws were described as "2BA", "4BA" etc., the odd numbers being rarely used, except in equipment made prior to the 1970s for telephone exchanges in the UK. This equipment made extensive use of odd-numbered BA screws, in order—it may be suspected—to reduce theft. BA threads are specified by British Standard BS 93:1951 "Specification for British Association (B.A.) screw threads with tolerances for sizes 0 B.A. to 16 B.A." While not related to ISO metric screws,

10011-582: The ISO metric screw thread are defined in international standard ISO 68-1 and preferred combinations of diameter and pitch are listed in ISO 261. The smaller subset of diameter and pitch combinations commonly used in screws, nuts and bolts is given in ISO 262 . The most commonly used pitch value for each diameter is the coarse pitch . For some diameters, one or two additional fine pitch variants are also specified, for special applications such as threads in thin-walled pipes. ISO metric screw threads are designated by

10152-688: The Morse #2 and the R8, whose prevalence was driven by the popularity of the mills built by Bridgeport Machines of Bridgeport, Connecticut . These mills so dominated the market for such a long time that "Bridgeport" is virtually synonymous with "manual milling machine". Most of the machines that Bridgeport made between 1938 and 1965 used a Morse taper #2, and from about 1965 onward most used an R8 taper. Many cutting tools exist for milling machines, including milling cutters, slitting cutters, gear cutters, end mills, etc. Pocket milling has been regarded as one of

10293-615: The National Machine Tool Builders Association (NMTB)) taper size of the tool. An improvement on CAT Tooling is Bridgeport Taper (BT) Tooling, which looks similar and can easily be confused with CAT tooling. Like CAT Tooling, BT Tooling comes in a range of sizes and uses the same NMTB body taper. However, BT tooling is symmetrical about the spindle axis, which CAT tooling is not. This gives BT tooling greater stability and balance at high speeds. One other subtle difference between these two toolholders

10434-474: The United States are still inch based. The numbers stamped on the head of the bolt are referred to the grade of the bolt used in certain application with the strength of a bolt. High-strength steel bolts usually have a hexagonal head with an ISO strength rating (called property class ) stamped on the head. And the absence of marking/number indicates a lower grade bolt with low strength. The property classes most often used are 5.8, 8.8, and 10.9. The number before

10575-470: The ability to move the spindle vertically along the Z-axis. This extra degree of freedom permits their use in diesinking, engraving applications, and 2.5D surfaces such as relief sculptures. When combined with the use of conical tools or a ball nose cutter , it also significantly improves milling precision without impacting speed, providing a cost-efficient alternative to most flat-surface hand- engraving work. CNC machines can exist in virtually any of

10716-457: The alternate form of the culture, for profit, causes misconceptions and stereotyping along with disruption of the original folk culture. Within the United States the commodification of culture is the mediated view of American society accepted as the culture and even advanced by the culture depicted; the example given is hip-hop and rap music artists stars "selling out". The United States, with media corporations less prone to governmental interference,

10857-554: The body, intimacy, public goods, animals and holidays. The earliest use of the word "commodification" dates from 1975.  Use of the concept of commodification became common with the rise of critical discourse analysis in  semiotics . The terms commodification and  commoditization  are sometimes used synonymously,  to describe the process of making  commodities  out of goods, services, and ideas. However, other authors distinguish them, with commodification used in social contexts to mean that

10998-412: The bolt and should be conducted on actual fasteners rather than calculated. If a bolt is tensioned beyond the proof load, it may behave in plastic manner due to yielding in the threads and the tension preload may be lost due to the permanent plastic deformations. When elongating a fastener prior to reaching the yield point, the fastener is said to be operating in the elastic region; whereas elongation beyond

11139-420: The boring. The success of marketing a culture entails distributing as much content as possible to the largest audience, causing disruption of everyday life. Elite media industries are ignorant or deny effects of mass marketing, by avoidance or by explaining that media has limited effects. There are many types of disruptions, some subtle, many obvious, including, propagation of misconceptions, loss of sense of place,

11280-400: The bows screwed to the frame with 00-72 (pronounced double ought – seventy two) size screws. To calculate the major diameter of "ought" size screws count the number of 0's and multiply this number by 0.013 and subtract from 0.060. For example, the major diameter of a 000-72 screw thread is .060 – (3 x .013) = 0.060 − 0.039 = .021 inches. For most size screws there are multiple TPI available, with

11421-401: The broad outlines are known, as summarized below. From a history-of-technology viewpoint, it is clear that the naming of this new type of machining with the term "milling" was an extension from that word's earlier senses of processing materials by abrading them in some way (cutting, grinding, crushing, etc.). Rotary filing long predated milling. A rotary file by Jacques de Vaucanson , circa 1760,

11562-419: The characteristic finish of a face milled surface. Revolution marks can have significant roughness depending on factors such as flatness of the cutter's end face and the degree of perpendicularity between the cutter's rotation axis and feed direction. Often a final pass with a slow feed rate is used to improve the surface finish after the bulk of the material has been removed. In a precise face milling operation,

11703-445: The coarse threads of a wood-screw or sheet-metal-screw threadform (but larger). The materials are usually carbon steel substrate with a coating of zinc galvanization (for corrosion resistance). The zinc coating may be bright yellow (electroplated), or dull gray ( hot-dip galvanized ). Bone screws have the medical use of securing broken bones in living humans and animals. As with aerospace and nuclear power, medical use involves some of

11844-470: The commercial practices and profitable tactics than they are to the holidays' origins. For some holidays, like Halloween, there are arguments that the commodification of the original holiday turned it into the celebrations that people now love. The commodification of other holidays, like Christmas, sparks arguments about undoing the commercialization and getting back to the intended spirit of the holiday. American author and feminist bell hooks described

11985-475: The commodification of nonhuman animals in food systems is directly linked to capitalist systems that prioritize "monopolistically inclined financial interests" over the well-being of humans, nonhumans, and the environment. Over 200 billion land and aquatic animals are killed every year to provide humans with animal products for consumption, which many scholars and activists have described as an " animal holocaust ". The extensive use of land and other resources for

12126-410: The commodification of online communities. Digital tracking, like cookies , have further commodified the use of the internet, giving each click, view, or stream, monetary value, even if it is an interaction with free content Public goods are goods for which users cannot be barred from accessing or using them, for failing to pay for them. However, such goods can also be commodified by value addition in

12267-437: The cultural commodification of race and difference as the dominant culture "eating the other". To hooks, cultural expressions of Otherness , even revolutionary ones, are sold to the dominant culture for their enjoyment. And any messages of social change are not marketed for their messages but used as a mechanism for the dominant ones to acquire a piece of the "primitive". Any interests in past historical culture almost always have

12408-548: The cutters have good support from the arbor and have a larger cross-sectional area than an end mill, quite heavy cuts can be taken enabling rapid material removal rates. These are used to mill grooves and slots. Plain mills are used to shape flat surfaces. Several cutters may be ganged together on the arbor to mill a complex shape of slots and planes. Special cutters can also cut grooves, bevels, radii, or indeed any section desired. These specialty cutters tend to be expensive. Simplex mills have one spindle, and duplex mills have two. It

12549-436: The difficulties and expense of doing so at the time. In 1908, Canadian P. L. Robertson was the first to make the internal-wrenching square socket drive a practical reality by developing just the right design (slight taper angles and overall proportions) to allow the head to be stamped easily but successfully, with the metal cold forming as desired rather than being sheared or displaced in unwanted ways. Practical manufacture of

12690-680: The dominant culture demands that the Other be offered as sign that progressive political change is taking place, that the American Dream can indeed be inclusive of difference, it invites a resurgence of essentialist cultural nationalism. Commodification of indigenous cultures refers to "areas in the life of a community which prior to its penetration by tourism have not been within the domain of economic relations regulated by criteria of market exchange" (Cohen 1988, 372). An example of this type of cultural commodification can be described through viewing

12831-409: The end of the 18th century. This development blossomed in the 1760s and 1770s. along two separate paths that soon converged : The first path was pioneered by brothers Job and William Wyatt of Staffordshire , UK, who patented in 1760 a machine that one might today best call a screw machine of an early and prescient sort. It made use of a leadscrew to guide the cutter to produce the desired pitch, and

12972-561: The first milling machine" or "the inventor of interchangeable parts". Such claims are oversimplified, as these technologies evolved over time among many people.) Peter Baida, citing Edward A. Battison's article "Eli Whitney and the Milling Machine," which was published in the Smithsonian Journal of History in 1966, exemplifies the dispelling of the " Great Man " image of Whitney by historians of technology working in

13113-410: The form of add-on heads to change horizontal mills to vertical mills (and later vice versa) have been commonly used. Even in the CNC era, a heavy workpiece needing machining on multiple sides lends itself to a horizontal machining center, while diesinking lends itself to a vertical one. In addition to horizontal versus vertical, other distinctions are also important: A milling machine is often called

13254-519: The form of products or services or both. Public goods like air and water can be subjected to commodification. Various subcultures have been argued to as having become commodified, for example the goth subculture , the biker subculture, the tattoo subculture, the witchcraft subculture, and others. Tourism has been analyzed in the context of commodification as a process of transforming local cultures and heritage into marketable goods. The commodification of tourism removes local culture from

13395-400: The forms of manual machinery, like horizontal mills. The most advanced CNC milling-machines, the multiaxis machine , add two more axes in addition to the three normal axes (XYZ). Horizontal milling machines also have a C or Q axis, allowing the horizontally mounted workpiece to be rotated, essentially allowing asymmetric and eccentric turning . The fifth axis (B axis) controls the tilt of

13536-409: The highest technology for fasteners; excellent performance, longevity, and quality are required, and reflected in prices. Bone screws are often made of relatively non-reactive stainless steel or titanium, and they often have advanced features such as conical threads, multistart threads, cannulation (hollow core), and proprietary screw drive types, some not seen outside of these applications. There are

13677-725: The history and suggest that just as much credit—in fact, probably more—belongs to various other inventors, including Robert Johnson of Middletown, Connecticut ; Captain John H. Hall of the Harpers Ferry armory; Simeon North of the Staddle Hill factory in Middletown; Roswell Lee of the Springfield armory; and Thomas Blanchard . (Several of the men mentioned above are sometimes described on the internet as "the inventor of

13818-461: The increase in luxury hotels catering to singles during Valentine's weekends . Digital commodification occurs when, a business or corporation uses information from an online community without their knowledge, for profit. The commodification of information allows a higher authority to make money rather than a collaborative system of free thoughts. Corporations such as Google , Apple , Facebook , Netflix , and Amazon accelerate and concentrate

13959-483: The internal-wrenching hexagon drive ( hex socket ) shortly followed in 1911. In the early 1930s American Henry F. Phillips popularized the Phillips-head screw , with a cross-shaped internal drive. Later improved -head screws were developed, more compatible with screwdrivers not of the exactly right head size: Pozidriv and Supadriv . Phillips screws and screwdrivers are to some extent compatible with those for

14100-633: The late 1700s (possibly even before 1678 when the book content was first published in parts). Eventually, lathes were used to manufacture wood screws, with the earliest patent being recorded in 1760 in England. During the 1850s, swaging tools were developed to provide a more uniform and consistent thread. Screws made with these tools have rounded valleys with sharp and rough threads. Once screw turning machines were in common use, most commercially available wood screws were produced with this method. These cut wood screws are almost invariably tapered, and even when

14241-410: The letter M followed by the major diameter of the thread in millimetres (e.g. M8 ). If the thread does not use the normal coarse pitch (e.g. 1.25 mm in the case of M8), then the pitch in millimeters is also appended with a multiplication sign (e.g. "M8×1" if the screw thread has an outer diameter of 8 mm and advances by 1 mm per 360° rotation). The nominal diameter of a metric screw

14382-410: The machine (e.g., a ball nose mill) or directly from the cutter's shape (e.g., a form tool such as a hobbing cutter). As material passes through the cutting area of a milling machine, the blades of the cutter take swarfs of material at regular intervals. Surfaces cut by the side of the cutter (as in peripheral milling) therefore always contain regular ridges. The distance between ridges and the height of

14523-491: The machine and have easy access to the cutting action by looking down upon it. Thus vertical mills are most favored for diesinking work (machining a mould into a block of metal). Heavier and longer workpieces lend themselves to placement on the table of a horizontal mill. Prior to numerical control , horizontal milling machines evolved first, because they evolved by putting milling tables under lathe-like headstocks. Vertical mills appeared in subsequent decades, and accessories in

14664-483: The machinist happened to need on any given day). In 1821 Hardman Philips built the first screw factory in the United States – on Moshannon Creek, near Philipsburg – for the manufacture of blunt metal screws. An expert in screw manufacture, Thomas Lever, was brought over from England to run the factory. The mill used steam and water power, with hardwood charcoal as fuel. The screws were made from wire prepared by "rolling and wire drawing apparatus" from iron manufactured at

14805-405: The mass production of screws continued to push unit prices lower and lower for decades to come, throughout the 19th century. The mass production of wood screws (metal screws for fixing wood) in a specialized, single-purpose, high-volume-production machine tool; and the low-count, toolroom -style production of machine screws or bolts (V-thread) with easy selection among various pitches (whatever

14946-405: The material and mechanical properties of imperial sized externally threaded fasteners. Some of the most common consensus standards for grades produced from carbon steels are ASTM A193, ASTM A307, ASTM A354, ASTM F3125, and SAE J429. Some of the most common consensus standards for grades produced from corrosion resistant steels are ASTM F593 & ASTM A193. The hand tool used to drive in most screws

15087-571: The material through the cutter slowly; most often it is some combination of these three approaches. The speeds and feeds used are varied to suit a combination of variables. The speed at which the piece advances through the cutter is called feed rate , or just feed ; it is most often measured as distance per time (inches per minute [in/min or ipm] or millimeters per minute [mm/min]), although distance per revolution or per cutter tooth are also sometimes used. There are two major classes of milling process: Many different types of cutting tools are used in

15228-431: The milling process. Milling cutters such as end mills may have cutting surfaces across their entire end surface, so that they can be drilled into the work piece (plunging). Milling cutters may also have extended cutting surfaces on their sides to allow for peripheral milling. Tools optimized for face milling tend to have only small cutters at their end corners. The cutting surfaces of a milling cutter are generally made of

15369-656: The most common being designated a Unified Coarse Thread (UNC or UN) and Unified Fine Thread (UNF or UF). Note: In countries other than the United States and Canada, the ISO Metric Screw Thread System is primarily used today. Unlike most other countries the United States and Canada still use the Unified (Inch) Thread System. However, both are moving over to the ISO Metric System. It is estimated that approximately 60% of screw threads in use in

15510-406: The most widely used operations in machining . It is extensively used in aerospace and shipyard industries. In pocket milling the material inside an arbitrarily closed boundary on a flat surface of a work piece is removed to a fixed depth. Generally flat bottom end mills are used for pocket milling. Firstly roughing operation is done to remove the bulk of material and then the pocket is finished by

15651-511: The newer types, but with the risk of damaging the heads of tightly fastened screws. Threadform standardization further improved in the late 1940s, when the ISO metric screw thread and the Unified Thread Standard were defined. Precision screws, for controlling motion rather than fastening, developed around the turn of the 19th century, and represented one of the central technical advances, along with flat surfaces, that enabled

15792-506: The notion that Maudslay had invented the slide rest, but this was incorrect; however, his lathes helped to popularize it. These developments of the 1760–1800 era, with the Wyatts and Maudslay as arguably the most important drivers, caused great increase in the use of threaded fasteners. Standardization of threadforms began almost immediately, but it was not quickly completed; it has been an evolving process ever since. Further improvements to

15933-443: The occasional use of mills for turning operations. This led to a new class of machine tools, multitasking machines (MTMs), which are purpose-built to facilitate milling and turning within the same work envelope. Milling is a cutting process that uses a milling cutter to remove material from the surface of a workpiece . The milling cutter is a rotary cutting tool , often with multiple cutting points. As opposed to drilling , where

16074-400: The orientation of the rotating spindle upon which the cutter is mounted. However, there are alternative classifications according to method of control, size, purpose and power source. In the vertical milling machine the spindle axis is vertically oriented. Milling cutters are held in the spindle and rotate on its axis. The spindle can generally be lowered (or the table can be raised, giving

16215-405: The perspective of Hawaiian cultural change since the 1950s. The Hawaiian Luau was once a traditional performance reserved for community members and local people, but through the rise of tourism, this tradition has lost part of its cultural meaning and is now mostly a "for profit" performance. Examples of profiting from love are the myriad "The Bachelorette" and "The Bachelor" television shows, and

16356-596: The pocket boundary. The direction of the tool path changes progressively and local acceleration and deceleration of the tool are minimized. This reduces tool wear. Milling machines evolved from the practice of rotary filing—that is, running a circular cutter with file -like teeth in the headstock of a lathe . Rotary filing and, later, true milling were developed to reduce time and effort spent hand-filing. The full story of milling machine development may never be known, because much early development took place in individual shops where few records were kept for posterity. However,

16497-447: The point is the ultimate tensile strength in MPa divided by 100. The number after the point is the multiplier ratio of yield strength to ultimate tensile strength. For example, a property class 5.8 bolt has a nominal (minimum) ultimate tensile strength of 500 MPa, and a tensile yield strength of 0.8 times ultimate tensile strength or 0.8 (500) = 400 MPa. Ultimate tensile strength

16638-407: The production of meat instead of grain for human consumption is a leading cause of malnutrition, hunger, and famine around the world. Commodification of humans have been discussed in various context, from slavery to surrogacy . Auctions of cricket players by Indian Premier League , Big Bash League and others is also discussed to be a case of human commodification. Virginity auctions are

16779-399: The relationship given in these standards between the thread size and the maximum width across the hexagonal flats (wrench size): In addition, the following non-preferred intermediate sizes are specified: Bear in mind that these are just examples and the width across flats is different for structural bolts, flanged bolts, and also varies by standards organization. The first person to create

16920-401: The revolution marks will only be microscopic scratches due to imperfections in the cutting edge. Gang milling refers to the use of two or more milling cutters mounted on the same arbor (that is, ganged) in a horizontal-milling setup. All of the cutters may perform the same type of operation, or each cutter may perform a different type of operation. For example, if several workpieces need

17061-437: The ridges depend on the feed rate, number of cutting surfaces, the cutter diameter. With a narrow cutter and rapid feed rate, these revolution ridges can be significant variations in the surface finish . The face milling process can in principle produce very flat surfaces. However, in practice the result always shows visible trochoidal marks following the motion of points on the cutter's end face. These revolution marks give

17202-416: The rolling process does not cut the grain of the metal. A self-tapping screw is designed to cut its own thread, usually in a fairly soft metal or plastic, in the same way as a wood screw (wood screws are actually self-tapping, but not referred to as such). ASME standards specify a variety of machine screws (aka stove bolts) in diameters ranging up to 0.75 in (19.05 mm). A machine screw or bolt

17343-505: The same diameter and pitch as ISO M6, the threads have different forms and are not compatible. BA threads are still common in some niche applications. Certain types of fine machinery, such as moving-coil meters and clocks, tend to have BA threads wherever they are manufactured. BA sizes were also used extensively in aircraft, especially those manufactured in the United Kingdom. BA sizing is still used in railway signalling, mainly for

17484-458: The same machine) to cut the next op. Today, CNC mills with automatic tool change and 4- or 5-axis control obviate gang-milling practice to a large extent. Milling is performed with a milling cutter in various forms, held in a collet or similar which, in turn, is held in the spindle of a milling machine. Mill orientation is the primary classification for milling machines. The two basic configurations are vertical and horizontal – referring to

17625-411: The same relative effect of bringing the cutter closer or deeper into the work), allowing plunge cuts and drilling. The depth to which blades cut into the work can be controlled with a micrometer adjustment nut . There are two subcategories of vertical mills: the bed mill and the turret mill. Turret mills are generally considered by some to be more versatile of the two designs. A third type also exists,

17766-424: The screw from the underside of the head to the tip is called the shank ; it may be fully or partially threaded with the distance between each thread called the pitch . Most screws are tightened by clockwise rotation, which is called a right-hand thread . Screws with a left-hand thread are used in exceptional cases, such as where the screw will be subject to counterclockwise torque , which would tend to loosen

17907-495: The size is given as a fraction; for sizes less than this an integer is used, ranging from 0 to 16. The integer sizes can be converted to the actual diameter by using the formula 0.060 + (0.013 × number). For example, a #4 screw is 0.060 + (0.013 × 4) = 0.060 + 0.052 = 0.112 inches in diameter. There are also screw sizes smaller than "0" (zero or ought). The sizes are 00, 000, 0000 which are usually referred to as two ought, three ought, and four ought. Most eyeglasses have

18048-566: The sizes were actually defined in metric terms, a 0BA thread having a 6 mm diameter and 1 mm pitch. Other threads in the BA series are related to 0BA in a geometric series with the common factors 0.9 and 1.2. For example, a 4BA thread has pitch p = 0.9 4 {\displaystyle \scriptstyle p=0.9^{4}}  mm (0.65 mm) and diameter 6 p 1.2 {\displaystyle \scriptstyle 6p^{1.2}}  mm (3.62 mm). Although 0BA has

18189-515: The slot was cut with a rotary file while the main spindle held still (presaging live tools on lathes 250 years later). Not until 1776 did the Wyatt brothers have a wood-screw factory up and running. Their enterprise failed, but new owners soon made it prosper, and in the 1780s they were producing 16,000 screws a day with only 30 employees—the kind of industrial productivity and output volume that would later become characteristic of modern industry but which

18330-426: The tapered shank is not obvious, they can be discerned because the threads do not extend past the diameter of the shank. Such screws are best installed after drilling a pilot hole with a tapered drill bit. The majority of modern wood screws, except for those made of brass, are formed on thread rolling machines. These screws have a constant diameter and threads with a larger diameter than the shank and are stronger because

18471-488: The termination of electrical equipment and cabling. BA threads are extensively used in Model Engineering where the smaller hex head sizes make scale fastenings easier to represent. As a result, many UK Model Engineering suppliers still carry stocks of BA fasteners up to typically 8BA and 10BA. 5BA is also commonly used as it can be threaded onto 1/8 rod. The Unified Thread Standard (UTS) is most commonly used in

18612-470: The thread in the wood. Early wood screws were made by hand, with a series of files, chisels, and other cutting tools, and these can be spotted easily by noting the irregular spacing and shape of the threads, as well as file marks remaining on the head of the screw and in the area between threads. Many of these screws had a blunt end, completely lacking the sharp tapered point on nearly all modern wood screws. Some wood screws were made with cutting dies as early as

18753-426: The tool is advanced along its rotation axis, the cutter in milling is usually moved perpendicular to its axis so that cutting occurs on the circumference of the cutter. As the milling cutter enters the work piece, the cutting edges (flutes or teeth) of the tool repeatedly cut into and exit from the material, shaving off chips (swarf) from the work piece with each pass. The cutting action is shear deformation; material

18894-407: The tool itself. When all of these axes are used in conjunction with each other, extremely complicated geometries, even organic geometries such as a human head can be made with relative ease with these machines. But the skill to program such geometries is beyond that of most operators. Therefore, 5-axis milling machines are practically always programmed with CAM . The operating system of such machines

19035-537: The tool movement is unidirectional. Zig-zag and zig tool paths are examples of linear tool paths. In zig-zag milling, material is removed both in forward and backward paths. In this case, cutting is done both with and against the rotation of the spindle. This reduces the machining time but increases machine chatter and tool wear . In zig milling, the tool moves only in one direction. The tool has to be lifted and retracted after each cut, due to which machining time increases. However, in case of zig milling surface quality

19176-428: The trifecta of leadscrew, slide rest, and change-gear gear train, all in the right proportions for industrial machining. In a sense he unified the paths of the Wyatts and Ramsden and did for machine screws what had already been done for wood screws, i.e., significant easing of production spurring commodification . His firm remained a leader in machine tools for decades afterward. A misquoting of James Nasmyth popularized

19317-406: The yield point is referred to as operating in the plastic region of the bolt material. If a bolt is loaded in tension beyond its proof strength, the yielding at the net root section of the bolt will continue until the entire section begins to yield and it has exceeded its yield strength. If tension increases, the bolt fractures at its ultimate strength. Mild steel bolts have property class 4.6, which

19458-405: Was 55°, and the depth and pitch varied with the diameter of the thread (i.e., the bigger the bolt, the coarser the thread). Spanners for Whitworth bolts are marked with the size of the bolt, not the distance across the flats of the screw head. The most common use of a Whitworth pitch nowadays is in all UK scaffolding . Additionally, the standard photographic tripod thread, which for small cameras

19599-816: Was one of the last of the simple machines to be invented. It first appeared in Mesopotamia during the Neo-Assyrian period (911-609) BC, and then later appeared in Ancient Egypt and Ancient Greece where it was described by the Greek mathematician Archytas of Tarentum (428–350 BC). By the 1st century BC, wooden screws were commonly used throughout the Mediterranean world in screw presses for pressing olive oil from olives and for pressing juice from grapes in winemaking . The first documentation of

19740-405: Was revolutionary at the time. Meanwhile, English instrument-maker Jesse Ramsden (1735–1800) was working on the toolmaking and instrument-making end of the screw-cutting problem, and in 1777 he invented the first satisfactory screw-cutting lathe . The British engineer Henry Maudslay (1771–1831) gained fame by popularizing such lathes with his screw-cutting lathes of 1797 and 1800, containing

19881-487: Was taking down records for posterity). Commodification Commodification is the process of transforming inalienable, free, or gifted things (objects, services, ideas, nature, personal information, people or animals) into commodities, or objects for sale. It has a connotation of losing an inherent quality or social relationship when something is integrated by a capitalist marketplace. Concepts that have been argued as being commodified include broad items such as

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