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28-470: On a lathe, mandrels are commonly mounted between centres and driven by a lathe dog (typically flanged or tapered mandrels), but may also be gripped in a chuck (typically threaded mandrels) where the outer face of work is to be machined. Threaded mandrels may also be mounted between centres. In addition to lathes, mandrels, more usually referred to as “arbours” are used to hold buffing wheels, circular saws, and sanding discs. Typically, such mandrels consist of

56-414: A composite material structure or part. The structure is cured, and the mandrel is removed. One problem with this type of process is difficulty in removing the mandrel from the completed work. A mandrel with a changeable shape can be more easily extracted. When heated above a certain temperature, the mandrel becomes elastic and can be manipulated into the desired shape and then cooled to become rigid again in

84-400: A drill bit to bore a centering hole. After the first few millimeters of cut, the centering mechanism may no longer be needed, although it will help the bit to bore without wandering in a deep hole. The sloping slots in the cylinder wall help carry the dust out. The kerf of the cut is designed to be slightly larger than the diameter of the rest of the hole saw so that it does not get jammed in

112-589: A hole cutter , is a saw blade of annular (ring) shape, whose annular kerf creates a hole in the workpiece without having to cut up the core material. It is used in a drill . Hole saws typically have a pilot drill bit (arbor) at their center to keep the saw teeth from walking. The fact that a hole saw creates the hole without needing to cut up the core often makes it preferable to twist drills or spade drills for relatively large holes (especially those larger than 25 millimetres (1.0 inch). The same hole can be made faster and using less power . The depth to which

140-437: A washer brazed onto the threaded end and an accompanying screw and second washer used to clamp the circular saw blade, sanding media, or other rotary tool onto the mandrel. While most mandrels are driven by direct connection to an electric motor or other engine, other mandrels may be driven by attachment to a bearing-supported, pulley -driven shaft. A 'triblet' is a type of mandrel found in jewelry manufacturing that

168-3169: A center. See also [ edit ] Lathe faceplate Mandrel Patents [ edit ] U.S. patent 108,325 —Buss, Charles. Improvement in lathe-dogs References [ edit ] ^ Colvin, Fred H.; Stanley, Frank A. (1945). American Machinists' Handbook and Dictionary of Shop Terms: A Reference Book of Machine Shop and Drawing Room Data, Methods and Definitions, 8th ed . New York and London: McGraw-Hill book Company. p. 1279. ^ War Department (1941). Technical Manual TM 10-445 The Machinist . pp. 55-56 ^ Colvin, Fred H.; Stanley, Frank A. (1943). Turning And Boring Practice . New York Toronto London: McGraw-Hill book company. pp. 16–17. ^ Bond, A. Russell, (1910). Handy Man's Workshop and Laboratory . New York; Munn & Co., Inc. p. 161 v t e Metalworking v t e Machining and computing Computer-aided engineering 2.5D CAD CAM G-code Numerical control (NC and CNC) Stewart platform Drilling and threading Die head Drill Drill bit Drill bit shank Drill bit sizes Drilling List of drill and tap sizes Tap and die Tap wrench Threading Grinding and lapping Abrasive Abrasive machining Angle grinder Bench grinder Coated abrasive Cylindrical grinder Diamond plate Flick grinder Grinding Grinding dresser Grinding machine Grinding wheel Jig grinder Lapping Sanding Sharpening stone Spark testing Surface grinder Tool and cutter grinder Machining Boring Broaching Electrical discharge machining Electrochemical machining Electron-beam machining End mill Engraving Facing Hobbing Jig borer Machine tool Machining Metal lathe Milling Milling cutter Pantograph Photochemical machining Planer Reamer Rotary transfer machine Shaper Skiving Turning Ultrasonic machining Machine tools Angle plate Chuck Collet Fixture Indexing head Jig Lathe center Machine taper Magnetic switchable device Mandrel Rotary table Wiggler Terminology Cutting fluid Machining vibrations Speeds and feeds Swarf Tolerance Tool and die making Tramp oil Workpiece Casting Fabrication Forming Jewellery Machining Metallurgy Smithing Tools and terminology Welding Retrieved from " https://en.wikipedia.org/w/index.php?title=Lathe_dog&oldid=1243951639 " Category : Lathes Hidden categories: Articles with short description Short description with empty Wikidata description Hole saw A hole saw (also styled holesaw ), also known as

196-433: A cylinder that is threaded on one end. There are many different types of mandrels for specialised applications. Examples include live chuck mandrels, live bull ring mandrels, and dead bull ring mandrels. An example of one type of mandrel is a shaped bar of metal inserted in, or next to, an item to be machined or bent in a certain pattern, e.g. in drawing metal tubing . Exhaust pipes for automobiles are frequently bent using

224-471: A faceplate, or sometimes a side of a chuck jaw. The workpiece passes through an aperture in the dog into which the work is secured by one or more setscrews or a clamp arrangement. The maximum cross sectional dimension of the workpiece is limited by the dimensions of the dog aperture. Lathe dogs are provided in straight tail or bent tail form, and may be single tail or double tail . A lathe dog designed to hold square, rectangular or odd-shaped work and having

252-422: A hole saw can cut is limited by the depth of its cup-like shape. Most hole saws have a fairly short aspect ratio of diameter to depth, and they are used to cut through relatively thin workpieces. However, longer aspect ratios are available for applications that warrant them. Common hole saw depths are 38, 45 and 60 mm and for drilling through e.g. (angled-) rooftop constructions also a depth 165 and 300 mm

280-429: A hole saw with relative ease. Some disadvantages include: Diamond hole saws are also called diamond core drill bits . Laser welded diamond core drill bits can be used in wet and dry drilling, but not all materials to be drilled are suitable for dry drilling. Very hard materials like reinforced concrete normally should be drilled with water, otherwise the excessive heat generated during the drilling process may cause

308-420: A mandrel during manufacture. The mandrel allows the exhaust pipes to be bent into smooth curves without undesirable creasing, kinking, or collapse. Molten glass may also be so shaped. A chuck is used on a lathe to hold pieces of wood, metal or plastic to be machined as they are turned. In this way, rods can be threaded, furniture legs are turned to a desired shape, and irregularly-shaped objects can be given

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336-454: A mandrel, the latter being basically a drill bit with threads to secure the saw. Mandrels are not recent inventions. Metal machining utilizing the spinning process has been recorded as far back as ancient Egyptian times. In metal spinning, a wood or metal spinning mandrel is used, the form of which corresponds with the internal contour of the part to be produced. This method securely clamps the raw material and allows for accurate machining into

364-415: A moveable portion secured typically by two cap screws is called a clamp dog . Bent tail dogs are able to engage directly with a driving faceplate slot or a chuck jaw but can crowd work off centre if clearance is not present between the dog tail and a closed end of the faceplate slot. Straight tail dogs do not present the issue of crowding work off centre but require at least one driving stud to be mounted on

392-424: A round shape. Several types of mandrel are used with lathes. Original expanding mandrels have a slightly tapered wedge that will expand to hold the item. A third type of mandrel is that which is used to hold circular saw blades, buffing wheels (used for polishing), and sanding discs onto drills , circular saws, and similar power tools. A mandrel of this type generally consists of a cylinder, threaded on one end, with

420-413: A shank extension, a diamond core drill can drill to depths many times its length. Saw teeth are used for most materials, such as wood , plastic , soft plaster , and metal . Diamond hole saws are used to bore holes in brick , concrete , glass, and stone . An adjustable hole saw consists of a number of thin metal saw blade-like strips, and a flat disc with a large number of grooves in one side and

448-554: A shank on the other. By snapping the blades into different grooves on the disc, a hole saw of a wide variety of sizes can be constructed. Another type of adjustable hole saw, also called a circle cutter, is formed by having one, two, or three adjustable teeth on a platform with a pilot bit. To cut out a hole of any size, the teeth need only be adjusted to the proper position. This type is available in sizes up to 300 mm (1 ft) and larger, and can be used to accurately cut large circles. The main advantage over conventional drill bits

476-407: Is not inserted into or held by a machine. Such mandrels vary in sizes and shapes, from small tapered metal rods (ring mandrels) to freestanding metal conic sections (used for making bracelets). Unlike with mechanical mandrels, the process is performed by hand. When shaping a ring or bangle with a triblet, it is typical to bend and solder the metal into a rough loop, then place it over the thinner end of

504-427: Is possible. Cutting with a hole saw is analogous to some machining operations, called trepanning in the trade, that swing a cutter analogous to a fly cutter in order to achieve a similar result of annular kerf and intact core. The saw consists of a metal cylinder, usually steel , mounted on an arbor . The cutting edge either has saw teeth formed in it or industrial diamonds embedded in it. The arbor can carry

532-406: Is shown with faceplate, drive stud, headstock center, dog and workpiece. [REDACTED] Bent tail lathe dog hooked on chuck jaw A lathe dog is a mechanical device typically made of cast iron, steel or aluminum that transmits rotary motion from a faceplate to a workpiece mounted between centers in a lathe. The tail of the dog is rotated by a slot in a driving faceplate, a stud mounted on

560-420: Is the hole saw's efficiency, because very little of the total material being removed is actually cut, which ultimately reduces the overall power requirement. Another advantage over drill bits is the wider size capability. For example, a 100 millimetres (3.9 inches) hole would require a huge twist drill or spade drill, unable to be properly driven by a pistol-grip drill or benchtop drill press; but it can be cut with

588-399: The cone - thus stretching the metal. Triblets are also used to repair squashed or damaged rings. A type of mandrel is also used in making reeds for double reed instruments such as the bassoon or oboe. Mandrels are also used in industrial composite fabrication, such as in filament winding . During the manufacturing process, resin-impregnated filaments are wound around a mandrel to create

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616-444: The desired final form. Since the material is clamped internally, there is no interference to the operator from the lathe/mandrel assembly during production. The traversing mandrel was introduced around 1700, and instantiated the design of a lathe mandrel able to slide axially in its bearings under the control of the operator, so that components having short lengths of thread could be produced, such as screws. The traversing mandrel

644-519: The faceplate. If the rotating mass of the dog setup is not balanced, eccentric motion of the work may occur. Counterbalancing or reduced spindle speed may be required. Care must be taken by the operator when using lathe dogs, as it is easy to get snagged on one. Use of headless setscrews, preferably of multiple-spline drive design, that do not protrude above the outer surface of the dog is recommended. A lathe dog may also be used with some indexing heads and other tools with similar faceplates that turn about

672-458: The hole. Holes saws for use with portable drills are commonly available in diameters from 6 to 130 mm, or in the US, ¼ to 6 inches. The only limit on the length of the cylinder, and thus depth of the hole, is the need to remove the bit from the hole to clear dust. A 300 mm (12 in) cylinder length is not uncommon, although shorter bits are usual. By breaking the core off from time to time and using

700-404: The mandrel is removed by increasing the temperature to melt the mandrel, allowing it to drain. In the production of steel core used for flexible drives, the center wire upon which the subsequent layers are wound is referred to as a Mandrel. This "center wire" may itself be composed of either a single wire or layers, depending on the sizing of the finished product. A hole saw usually attaches to

728-437: The mandrel. Once done, the next step is to strike the work in a downward motion with a hammer or other tool to push it towards the wider end. This forces the metal to adopt a true ring-shape. Triblets with measurements cut into them (called 'ring size sticks') can also be used as a quick way of measuring the final size of a ring. A triblet can also be used to make a ring slightly bigger by gently tapping it in order to force it down

756-404: The new shape. It can then be used in the filament winding process. Once the composite part is cured, the mandrel can be reheated until elastic and easily removed from the cured part. These types of mandrels can be used repeatedly. A mandrel can also be made of a metal alloy that melts at low temperature. In this process, the composite is laid over the mandrel, heated to cure the material, and then

784-400: Was primarily employed by watchmakers and ornamental turners during this era. Eventually the device was superseded by a mandrel-driven device called a leadscrew , which uses a train of gears that can be altered as required for the turning application. Lathe dog Mechanical component of a lathe [REDACTED] Straight tail lathe dogs. A setup

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