The Watchmaker And His Lathe Pdf 14 _VERIFIED_
A lathe is a machine that rotates the workpiece about an axis of rotation to perform various operations such as turning, undercutting, knurling, drilling, facing, boring, and cutting, with lathe cutting tools that are applied to the workpiece to create an object with symmetry about that axis.For general purpose work, the tool used in is a single point tool, but for special operations, multipoint tools may use. Watch the below-mentioned video to get understand about lathe machine operation.In a lathe machine work, different operations require different types of lathe cutting tools, according to the process of using the lathe cutting tools. which are as follow,if(typeof ez_ad_units!='undefined')ez_ad_units.push([[580,400],'theengineerspost_com-medrectangle-3','ezslot_3',683,'0','0']);__ez_fad_position('div-gpt-ad-theengineerspost_com-medrectangle-3-0');
The Watchmaker And His Lathe Pdf 14
Following are the types of lathe cutting tools used in lathe machine:Turning tool.Chamfering tool.Thread cutting tool.Internal thread cutting tool.Facing tool.Grooving tool.Forming tool.Boring tool.Parting-off tool.Counterboring toolUndercutting toolAccording to the method of applying feedRight-hand toolLeft-hand toolRound NoseWatch Slideshow Of This Post:According to the method of using the tool1. Turning ToolThere are mainly two classes of turning tool:
The tool may be a bit type inserted in a boring bar or holder, or forged type having a tool shank. The figure shows an H.S.S. tool bit inserted in a boring bar.A boring bar is made of mild steel with slots or holes cut into it to accommodate the tool bit which is locked by an Allen screw. The amount of projection of the cutting edge of the tool from the centre of the bar determines the finished hole diameter of the work.The bit is generally inserted at right angles to the centre line of the bar for boring a continuous hole passing from one end to the other end.8.1 Different Design of The Boring ToolThe bit is set at a single to the axis projecting beyond the end of the bar for boring a blind hole.if(typeof ez_ad_units!='undefined')ez_ad_units.push([[300,250],'theengineerspost_com-leader-3','ezslot_10',677,'0','0']);__ez_fad_position('div-gpt-ad-theengineerspost_com-leader-3-0');A tool bit having two cutting edges at it two ends is used for quick machining.A wide double-bladed cutter is inserted in the boring bar to finish the boring operation.Two or more bits may be inserted in a boring bar for different diameters in one setting.8.2 Boring Bars:Boring bars are held in the tailstock for boring small holes ranging from 12 to 100 mm.For boring larger hole diameters, boring bars are gripped by two clamp blocks and held in the tool post.For precision boring or boring in odd size work that is supported on cross-slide, the bar is supported on centres and is made to revolve.8.3 Clearance for Boring ToolIn a boring tool, the tool cutting edge most have sufficient front clearance to clear the work.To strengthen the tool point double clearance, primary and secondary, is provided.The smaller be the hole diameter the larger should be the front clearance.Larger clearance angle necessitates the reduction in rake angle in a boring tool.The nose of the tool is straight or round according to the type of finish desired.if(typeof ez_ad_units!='undefined')ez_ad_units.push([[336,280],'theengineerspost_com-leader-1','ezslot_16',560,'0','0']);__ez_fad_position('div-gpt-ad-theengineerspost_com-leader-1-0');9. Counterboring ToolThe counterboring operation can be performed by an ordinary boring tool. The tool cutting edge is so ground that it can leave a shoulder after turning. A counterbore having multiple cutting edges is commonly used.10. Undercutting ToolUndercutting or grooving tool has a point and form of the cutting edge exactly similar to the form of the required groove.Clearance angle is given at all the sides of the tool. For the recessing groove cutting edge, the longitudinal feed is employed. The front clearance angle depends upon the bore of the work.11. Parting Off ToolA parting off tool is normally forged and used as bits for cemented carbide tipped tools. Parting off tool is made as narrow as possible to remove the minimum of metal.The width of the cutting edge range from 3 to 12 mm only. The length of the cutting tool which inserts into the work should be slightly longer than the radius of the bar stock being machined.As the tool penetrates deep into the work, clearance is provided all around the tool cutting edge to prevent it from rubbing against the work surface.As the tool is purely ended cutting it has no side rake slight back rake is provided on the tool to promote an easy flow of the ships.Read also: Cutting speed, Feed, Depth of cut & Machining time in lathe machineAccording to The Method of Applying FeedRight-hand toolLeft-hand toolRound Nose1. Right-Hand ToolA right-hand tool is shown in the figure. Is that which is fed from lathe bed, i.e. from the tailstock to the headstock end when operations like turning, thread cutting, etc are performed.A right-hand tool is formed on its left-hand end when viewed from the top with its nose pointing away from the operator.
A lathe (/leɪð/) 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.
Lathes are used in woodturning, metalworking, metal spinning, thermal spraying, parts reclamation, and glass-working. Lathes can be used to shape pottery, the best-known design being the Potter's wheel. Most suitably equipped metalworking lathes can also be used to produce most solids of revolution, plane surfaces and screw threads or helices. Ornamental lathes can produce three-dimensional solids of incredible complexity. The workpiece is usually held in place by either one or two centers, at least one of which can typically be moved horizontally to accommodate varying workpiece lengths. Other work-holding methods include clamping the work about the axis of rotation using a chuck or collet, or to a faceplate, using clamps or dog clutch.
Examples of objects that can be produced on a lathe include screws, candlesticks, gun barrels, cue sticks, table legs, bowls, baseball bats, pens, musical instruments (especially woodwind instruments), and crankshafts.
The lathe is an ancient tool. The earliest evidence of a lathe dates back to Ancient Egypt around 1300 BC. There is also tenuous evidence for its existence at a Mycenaean Greek site, dating back as far as the 13th or 14th century BC.
The lathe was very important to the Industrial Revolution. It is known as the mother of machine tools, as it was the first machine tool that led to the invention of other machine tools. The first fully documented, all-metal slide rest lathe was invented by Jacques de Vaucanson around 1751. It was described in the Encyclopédie.
In 1718 Russian engineer Andrey Nartov invented one of the first lathes with a mechanical cutting tool-supporting carriage and a set of gears (also known as a compound rest or slide rest) with the first to invent such a lathe probably being Leonardo da Vinci.
An important early lathe in the UK was the horizontal boring machine that was installed by Jan Verbruggen in 1772 in the Royal Arsenal in Woolwich. It was horse-powered and allowed for the production of much more accurate and stronger cannon used with success in the American Revolutionary War in the late 18th century. One of the key characteristics of this machine was that the workpiece was turning as opposed to the tool, making it technically a lathe. Henry Maudslay, who later developed many improvements to the lathe, worked at the Royal Arsenal from 1783, being exposed to this machine in the Verbruggen workshop. A detailed description of Vaucanson's lathe was published decades before Maudslay perfected his version. It is likely that Maudslay was not aware of Vaucanson's work, since his first versions of the slide rest had many errors that were not present in the Vaucanson lathe.
During the Industrial Revolution, mechanized power generated by water wheels or steam engines was transmitted to the lathe via line shafting, allowing faster and easier work. Metalworking lathes evolved into heavier machines with thicker, more rigid parts. Between the late 19th and mid-20th centuries, individual electric motors at each lathe replaced line shafting as the power source. Beginning in the 1950s, servomechanisms were applied to the control of lathes and other machine tools via numerical control, which often was coupled with computers to yield computerized numerical control (CNC). Today manually controlled and CNC lathes coexist in the manufacturing industries.
Almost all lathes have a bed, which is (almost always) a horizontal beam (although CNC lathes commonly have an inclined or vertical beam for a bed to ensure that swarf, or chips, falls free of the bed). Woodturning lathes specialized for turning large bowls often have no bed or tail stock, merely a free-standing headstock and a cantilevered tool rest.
At one end of the bed (almost always the left, as the operator faces the lathe) is a headstock. The headstock contains high-precision spinning bearings. Rotating within the bearings is a horizontal axle, with an axis parallel to the bed, called the spindle. Spindles are often hollow and have an interior Morse taper on the spindle nose (i.e., facing to the right / towards the bed) by which work-holding accessories may be mounted to the spindle. Spindles may also have arrangements for work-holding on the left-hand end of the spindle with other tooling arrangements for particular tasks. (i.e., facing away from the main bed) end, or may have a hand-wheel or other accessory mechanism on their outboard end. Spindles are powered and impart motion to the workpiece.