Lathe dog

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Straight tail lathe dogs. A setup is shown with faceplate, drive stud, headstock center, dog and workpiece. LatheDrivePlate-carriers.jpg
Straight tail lathe dogs. A setup is shown with faceplate, drive stud, headstock center, dog and workpiece.
Bent tail lathe dog hooked on chuck jaw. Lathedog.jpg
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. [1] The tail of the dog is rotated by a slot in a driving faceplate, a stud mounted on 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 a moveable portion secured typically by two cap screws is called a clamp dog. [2] 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. [3] Straight tail dogs do not present the issue of crowding work off centre but require at least one driving stud to be mounted on the faceplate. If the rotating mass of the dog setup is not balanced, eccentric motion of the work may occur. [4] 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 a center.

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Lathe Machine tool which rotates the work piece on its axis

A lathe is a machine tool that rotates a workpiece about an axis of rotation to perform various operations such as cutting, sanding, knurling, drilling, deformation, facing, and turning, with tools that are applied to the workpiece to create an object with symmetry about that axis.

Shaper Machine that uses linear motion to cut. Ot is also used to grind the surface

A shaper is a type of machine tool that uses linear relative motion between the workpiece and a single-point cutting tool to machine a linear toolpath. Its cut is analogous to that of a lathe, except that it is (archetypally) linear instead of helical.

Machining Material-removal process; Manufacturing process

Machining is a process in which a material 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, in contrast to additive manufacturing, which uses controlled addition of material. Exactly what the "controlled" part of the definition implies can vary, but it usually implies the use of machine tools.

Woodturning Craft

Woodturning is the craft of using the wood lathe with hand-held tools to cut a shape that is symmetrical around the axis of rotation. Like the potter's wheel, the wood lathe is a simple mechanism that can generate a variety of forms. The operator is known as a turner, and the skills needed to use the tools were traditionally known as turnery. In pre-industrial England, these skills were sufficiently difficult to be known as 'the misterie' of the turners guild. The skills to use the tools by hand, without a fixed point of contact with the wood, distinguish woodturning and the wood lathe from the machinist's lathe, or metal-working lathe.

Mandrel

A mandrel, mandril, or arbor is a gently tapered cylinder against which material can be forged or shaped, or a flanged or tapered or threaded bar that grips a workpiece to be machined in a lathe. A flanged mandrel is a parallel bar of a specific diameter with an integral flange towards one end, and threaded at the opposite end. Work is gripped between the flange and a nut on the thread. A tapered mandrel has a taper of approximately 0.005 inches per foot and is designed to hold work by being driven into an accurate hole on the work, gripping the work by friction. A threaded mandrel may have a male or female thread, and work which has an identical thread is screwed onto the mandrel.

Collet type of chuck

A collet is a subtype of chuck that forms a collar around an object to be held and exerts a strong clamping force on the object when it is tightened, usually by means of a tapered outer collar. It may be used to hold a workpiece or a tool.

Chuck (engineering) Clamp used to hold an object with radial symmetry, especially a cylinder

A chuck is a specialized type of clamp used to hold an object with radial symmetry, especially a cylinder. In a drill, a mill and a transmission, a chuck holds the rotating tool; in a lathe, it holds the rotating workpiece.

Machine taper

A machine taper is a system for securing cutting tools or toolholders in the spindle of a machine tool or power tool. A male member of conical form fits into the female socket, which has a matching taper of equal angle.

Turning Machining process

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.

Vise Device to secure an object to be worked on

A vise or vice is a mechanical apparatus used to secure an object to allow work to be performed on it. Vises have two parallel jaws, one fixed and the other movable, threaded in and out by a screw and lever.

Metal lathe

A metal lathe or metalworking lathe is a large class of lathes designed for precisely machining relatively hard materials. They were originally designed to machine metals; however, with the advent of plastics and other materials, and with their inherent versatility, they are used in a wide range of applications, and a broad range of materials. In machining jargon, where the larger context is already understood, they are usually simply called lathes, or else referred to by more-specific subtype names. These rigid machine tools remove material from a rotating workpiece via the movements of various cutting tools, such as tool bits and drill bits.

Indexing head dividing head

An indexing head, also known as a dividing head or spiral head, is a specialized tool that allows a workpiece to be circularly indexed; that is, easily and precisely rotated to preset angles or circular divisions. Indexing heads are usually used on the tables of milling machines, but may be used on many other machine tools including drill presses, grinders, and boring machines. Common jobs for a dividing head include machining the flutes of a milling cutter, cutting the teeth of a gear, milling curved slots, or drilling a bolt hole circle around the circumference of a part.

Lathe faceplate Workholding accessory

A lathe faceplate is a basic workholding accessory for a wood or metal turning lathe. It is a circular metal plate which fixes to the end of the lathe spindle. The workpiece is then clamped to the faceplate, typically using t-slot nuts in slots in the faceplate, or less commonly threaded holes in the faceplate itself.

Boring (manufacturing)

In machining, boring is the process of enlarging a hole that has already been drilled by means of a single-point cutting tool, such as in boring a gun barrel or an engine cylinder. Boring is used to achieve greater accuracy of the diameter of a hole, and can be used to cut a tapered hole. Boring can be viewed as the internal-diameter counterpart to turning, which cuts external diameters.

Turret lathe

The turret lathe is a form of metalworking lathe that is used for repetitive production of duplicate parts, which by the nature of their cutting process are usually interchangeable. It evolved from earlier lathes with the addition of the turret, which is an indexable toolholder that allows multiple cutting operations to be performed, each with a different cutting tool, in easy, rapid succession, with no need for the operator to perform set-up tasks in between or to control the toolpath. The latter is due to the toolpath's being controlled by the machine, either in jig-like fashion, via the mechanical limits placed on it by the turret's slide and stops, or via digitally-directed servomechanisms for computer numerical control lathes.

Fixture (tool)

A fixture is a work-holding or support device used in the manufacturing industry. Fixtures are used to securely locate and support the work, ensuring that all parts produced using the fixture will maintain conformity and interchangeability. Using a fixture improves the economy of production by allowing smooth operation and quick transition from part to part, reducing the requirement for skilled labor by simplifying how workpieces are mounted, and increasing conformity across a production run.

In engineering, a dog is a tool or part of a tool, such as a pawl, that prevents or imparts movement through physical engagement. It may hold another object in place by blocking it, clamping it, or otherwise obstructing its movement. Or it may couple various parts together so that they move in unison – the primary example of this being a flexible drive to mate two shafts in order to transmit torque. Some devices use dog clutches to lock together two spinning components. In a manual transmission, the dog clutches, or "dogs" lock the selected gear to the shaft it rotates on. Unless the dog is engaged, the gear will simply freewheel on the shaft.

Tailstock

A tailstock, also known as a foot stock, is a device often used as part of an engineering lathe, wood-turning lathe, or used in conjunction with a rotary table on a milling machine.

Grinding (abrasive cutting)

Grinding is a type of abrasive machining process which uses grinding wheel as cutting tool.

A woodworking vise is a type of vise adapted to the various needs of woodworkers and woodworking. Several types have evolved to meet differing primary functions, falling under the general categories of front and end vises, reflecting their positions on a workbench.

References

  1. 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.
  2. War Department (1941). Technical Manual TM 10-445 The Machinist. pp. 55-56
  3. Colvin, Fred H.; Stanley, Frank A. (1943). Turning And Boring Practice. New York Toronto London: McGraw-Hill book company. pp. 16–17.
  4. Bond, A. Russell, (1910). Handy Man's Workshop and Laboratory. New York; Munn & Co., Inc. p. 161