· A workshop is a series of educational and work sessions. Small groups of people meet together over a short period of time to concentrate on a defined area of concern
· Purposes for workshops may vary
Typically, a workshop has two components:
Example: Presenting theory in lectures
Examples: Doing a project, producing a product, or writing a paper
WORKSHOP CONSISTS OF SIX SHOPS :
· MEASURING TOOLS IN WORKSHOP
· VERNIER CALLIPER
· STEEL RULES
CALLIPERS AND DIVIDERS
1. MACHINE SHOP
Machine shops deal mainly with fabricating custom metal parts and tools for a variety of industries, such as automotive and aerospace. Conventional machining operations allow for mass productions of screws, pistons and gears, with a high level of accuracy. Inventors and crafters use machining equipment and tools for their projects, as well. No machine shop is complete without these essential tools of the trade.
2. SMITHY SHOP
A blacksmith is a person who creates objects from wrought iron or steel by forging the metal; that is, by using tools to hammer, bend, and cut (compare to whitesmith). Blacksmiths produce objects such as gates, grilles, railings, light fixtures, furniture, sculpture, tools, agricultural implements, decorative and religious items, cooking utensils, and weapons.
Despite common usage, the person who shoes horses is a farrier (though a blacksmith may fabricate the shoes). Many farriers have carried out both trades, but most modern or engineering smiths do not.
1 Origin of the term
2 Smithing process
· Origin of the term
The term "blacksmith" comes from the activity of "forging" iron or the "Black" metal - so named due to the color of the metal after being heated (a key part of the blacksmithing process). The term "forging" means to shape metal by heating and hammering.
· Smithing process
Blacksmiths work primarily with wrought iron and steel. The "black" in "blacksmith" refers to the black fire scale, a layer of oxides that forms on the surface of the metal during heating. The word "smith" derives from an old word, "smite" (to hit). Thus, a blacksmith is a person who hits black metal.
Blacksmiths work by heating pieces of wrought iron or steel, until the metal becomes soft enough to be shaped with hand tools, such as a hammer, anvil and chisel. Heating is accomplished by the use of a forge fueled by propane, natural gas, coal, charcoal, coke or oil.
Some modern blacksmiths may also employ an oxyacetylene or similar blowtorch for more localized heating. Induction heating methods are gaining popularity among modern blacksmiths.
Colour isimportant for indicating the temperature and workability of the metal: As iron is heated to increasing temperatures, it first glows red, then orange, yellow, and finally white. The ideal heat for most forging is the bright yellow-orange color appropriately known as a "forging heat". Because they must be able to see the glowing color of the metal, some blacksmiths work in dim, low-light conditions. Most work in well-lit conditions. The key is to have consistent lighting which is not too bright. Direct sunlight obscures the colors.
The techniques of smithing may be roughly divided into forging (sometimes called "sculpting"), welding, heat treating, and finishing.
Forging is the process in which metal is shaped by hammering. Forging is different from machining in that material is not removed by it; rather the iron is hammered into shape. Even punching and cutting operations (except when trimming waste) by smiths will usually re-arrange metal around the hole, rather than drilling it out as swarf.
There are seven basic operations or techniques employed in forging: drawing down, shrinking (a type of upsetting), bending, upsetting, Swageing, punching and Forge welding.
These operations generally employ hammer and anvil at a minimum, but smiths will also make use of other tools and techniques to accommodate odd-sized or repetitive jobs.
Drawing lengthens the metal by reducing one or both of the other two dimensions. As the depth is reduced, the width narrowed, or the piece is both lengthened or "drawn out."
As an example of drawing, a smith making a chisel might flatten a square bar of steel, lengthening the metal, reducing its depth but keeping its width consistent.
Drawing does not have to be uniform. A taper can result as in making a wedge or a woodworking chisel blade. If tapered in two dimensions, a point results.
Drawing can be accomplished with a variety of tools and methods. Two typical methods using only hammer and anvil would be hammering on the anvil horn, and hammering on the anvil face using the cross peen of a hammer.
Another method for drawing is to use a tool called a fuller, or the peen of the hammer, to hasten the drawing out of a thick piece of metal. (The technique is called fullering from the tool.) Fullering consists of hammering a series of indentations with corresponding ridges, perpendicular to the long section of the piece being drawn. The resulting effect will look somewhat like waves along the top of the piece. Then the hammer is turned over to use the flat face and the tops of the ridges are hammered down level with the bottoms of the indentations. This forces the metal to grow in length (and width if left unchecked) much faster than just hammering with the flat face of the hammer.
Shrinking, while similar to upsetting, is essentially opposite the process of drawing. As the edge of a flat piece is curved—as in the making of a bowl shape—the edge will become wavy as the material bunches up in a shorter radius. At this point the wavy portion is heated and the waves are gently hammered flat to conform to the desired shape. If you were to compare the edge of the new shape to the original piece, you would discover that the material is now thicker. This change in thickness is due to the excess material that formed the waves being pushed into a uniform edge having a smaller radius than before.
Heating iron to a "forging heat" allows bending as if it were a soft, ductile metal, like copper or silver.
Bending can be done with the hammer over the horn or edge of the anvil or by inserting a bending fork into the Hardy Hole (the square hole in the top of the anvil), placing the work piece between the tines of the fork, and bending the material to the desired angle. Bends can be dressed and tightened, or widened, by hammering them over the appropriately shaped part of the anvil.
Some metals are "hot short", meaning they lose their tensile strength when heated. They become like Plasticine: although they may still be manipulated by squeezing, an attempt to stretch them, even by bending or twisting, is likely to have them crack and break apart. This is a problem for some blade-making steels, which must be worked carefully to avoid developing hidden cracks that will cause failure in the future. Although rarely hand-worked, titanium is notably hot short. Even such common smithing processes as decoratively twisting a bar are impossible with it.
Upsetting is the process of making metal thicker in one dimension through shortening in the other. One form is to heat the end of a rod and then hammer on it as one would drive a nail: the rod gets shorter, and the hot part widens. An alternative to hammering on the hot end is to place the hot end on the anvil and hammer on the cold end.
Punching may be done to create a decorative pattern, or to make a hole. For example, in preparation for making a hammerhead, a smith would punch a hole in a heavy bar or rod for the hammer handle. Punching is not limited to depressions and holes. It also includes cutting, slitting, and drifting—all done with a chisel.
The five basic forging processes are often combined to produce and refine the shapes necessary for finished products.
3. FOUNDRY SHOP
1. Showel: It consists of iron pan with a wooden handle. It can be used for mixing and conditioning the sand.
2. Trowels: These are used for finishing flat surfaces and comers inside a mould. Common shapes of trowels are shown as under. They are made of iron with a wooden handle.
3. Lifter: A lifter is a finishing tool used for repairing the mould and finishing the mould sand. Lifter is also used for removing loose sand from mould.
4. Hand riddle: It is used for ridding of sand to remove foreign material from it. It consists of a wooden frame fitted with a screen of standard wire mesh at the bottom.
5. Strike off bar: It is a flat bar, made of wood or iron to strike off the excess sand from the top of a box after ramming.
Its one edge made beveled and the surface perfectly smooth and plane
6. Vent wire: It is a thin steel rod or wire carrying a pointed edge at one end and a wooden handle or a bent loop at the other. After ramming and striking off the excess sand it is used to make small holes, called vents, in the sand mould to allow the exit of gases and steam during casting.
7. Rammers: Rammers are used for striking the sand mass in the moulding box to pack it closely around one pattern. Common types of rammers are shown as under.
8. Swab: It is a hemp fiber brush used for moistening the edges of sand mould, which are in contact with the pattern surface, before withdrawing the pattern. It is also used for coating the liquid blacking on the mould faces in dry sand moulds.
9. Sprue pin: It is a tapered rod of wood or iron, which is embedded in the sand and later withdrawn to produce a hole, called runner, through which the molten metal is poured into the mould.
10. Sprue cutter: It is also used for the same purpose as a sprue pin, but there is a marked difference between their uses in that the cutter is used to produce the hole after ramming the mould. It is in the form of a tapered hollow tube, which is inserted in the sand to produce the hole
4. CARPENTRY SHOP
· Measuring Tools
Tools are necessary for accurate measurement before beginning a woodworking project. A tape measure in the form of a retractable metal ribbon is flexible and available in lengths up to 300 feet. A 12-inch ruler is ideal for measuring on smaller projects such as crafts and drawer fronts. Protractors are ideal for measuring angles on frames, cabinets and crafts among other projects. A level is a metal bar containing a ball or air pocket inside of a plastic vial where the evenness of the ball or air pocket indicates the evenness of a piece of wood when set onto the wood.
· Cutting Tools
Cutting tools include a variety of saws, including hand saws and power saws. Hand saws include keyhole saws for jabbing holes into soft wood such as plywood; dovetail saws for cutting indentations into the ends of wooden boards; and panel saws for cutting across the grain of a piece of wood. Power saws include chainsaws for making large cuts, jigsaws for making irregular cuts and curvatures and miter saws for crosscuts.
· Shaping Tools
Tools for shaping and carving are necessary when creating elaborate designs on a piece of wood. A plane is useful for thinning a small piece of wood, slimming a cabinet door, straightening a piece of wood with warps or twists and shaving rough spots from the face of a piece of wood. Chisels feature a shaped blade for carving and include bevel-edged chisels for dovetail joints, corner chisels for finishing mortises, flooring chisels for tongue-and-groove panels, paring chisels for fitting joints and carving chisels such as gouges, skews and V-grooves for creating designs.
· Assembly Tools
Common tools for assembling parts of a woodworking project include hammers, drills and screwdrivers. A hammer drives nails to attach two pieces of wood. Common hammers for woodworking include claw hammers for pulling nails, rip hammers for framing, finishing hammers or carpenter's mallets with smooth faces and rubber heads for setting dowels. Wooden mallets are useful for driving chisels. Clamps are useful for holding objects in place after gluing them together. A screwdriver is useful for attaching screws that hold together two separate pieces of wood. A drill bores holes into wood sometimes to create a path for a screw or dowel. A drill is also useful for screwing together thick pieces of wood.
· Finishing Tools
Finishing tools help enhance the aesthetic of a woodworking project. Sandpaper scrapes and smooths rough spots along a piece of wood. Sandpaper is available in a variety of grain sizes and roughness to be compatible with different textures of wood. Electric belt sanders are convenient for sanding large projects.
TOOLS OF CARPENTRY SHOP
5. FITTING SHOP
· Fitting is the process of assembling various parts manufactured in the machine shop.
The bench work and fitting plays an important role in every engineering workshop to complete and finish the job to the desired accuracy. The work carried out by hand at the bench is called bench work. Whereas fitting is the assembling of parts together by fitting, chipping, sawing, fore capping, tapping etc. necessary after the machine operation. This may or may not be carried out of the bench.
The tools use in filling practice may be classified into the following group:
1) Holding tools 2) Drilling tools
3) Striking tools 4) Measuring tools
5) Cutting tools 6) Marking tools
7) Scrapping tools
Holding tools (Vices): The holding tools are vice are required to hold the work firmly. Following are the various types of vice for different purposes. Following are the different types of holding tools:-
§ Bench Vice
§ Hand Vice
§ Pipe Vice
§ Leg Vice
§ Pin Vice
Striking tools (Hammers): A hammer is a tool that is used for hammering nails, fitting parts, or breaking objects. A hammer has a head which is the heaviest part of the tool. It also has a back, and it's primary use is to remove nailsThe striking tools are hammers are used to strike the job or tool. A hammer consists of a bead, striking face, peen and a shaft or handle.
TYPES OF HAMMERS
Types of Hammers
§ Ball Pin Hammer
§ Cross Pin Hammer
§ Straight Pin Hammer
§ Double Faced Hammer
§ Soft Hammer
Cutting Tools: The chief cutting tools used in fitting are cold, chisels, and files.
Cold Chisels: The cold chisel is an important cutting tool used by the filter. These are used to cut the cold metal and are made by forging from cast tools steel of octagonal cross section.
Types of Chisel
§ Flat Chisel
§ Cross Out Chisel or Cape Chisel
§ Half Round Chisel
§ Size Chisel
Files: A file is a hardened piece of high grade steel with slanting rows of teeth. It is used to get smooth or fit metal parts. It cuts of all metals expect hardened steel and if cuts only on the forward stroke.
The files are classified according to the size file.
Cut of Teeth: The files the teeth are cut parallel to each other running across the faces.
Shape of File: The file according to their shape or cross section is classified.
§ Flat File
§ Hand File
§ Square File
§ Piller File
§ Round File
§ Half Round File
Filling is required after shipping for cutting operation to remove bur a clean the face of the cuts and to finish the final shape work piece.
Method Filling: The following three methods are commonly used for filling.
§ Cross Filling
§ Straight Filling
§ Draw Filling
· WELDING SHOP
. A welding position, or station, is a set of welding equipment for operations that require some degree of participation by a welder. A welding line combines several welding stations.
Welding stations may be used in arc welding, resistance welding, gas welding, electron-beam welding, or other methods. The welding equipment includes the welding machine, power supplies, and devices directly used to conduct the welding process, jigs and fixtures for the rapid assembly of the parts to be welded, for holding the parts during welding, and for preventing or reducing warpage of the welded articles, auxiliary equipment used for transporting the parts during welding and for mounting and transporting the welding apparatus, and various other tools used by the welder. Various transport means and instruments for controlling weld quality are also used
HOW WELDING WORKS
in the welding process. The technical characteristics of welding equipment are determined by the welding method chosen, the type of production, and the degree of mechanization, that is, whether manual, semiautomatic, or automatic welding is performed.
A welding station is a section of a production area where a power supply, current-carrying conductors, and necessary jigs, fixtures, and welder’s tools are located. In order to protect personnel in the area from radiation, the welding station is enclosed by curtains or panels. Fixed automated stations are widely used in modern manufacturing processes; such stations are located in manufacturing shops. Mobile stations are used in the field for welding large objects in construction and repair work.
Welders. Welding stations include power supplies and equipment for regulation of the arc during welding. Power supplies used in welding should provide a convenient, continuous or step control and must satisfy general requirements for electric machines and equipment. Welding transformers, generators, and rectifiers are used in electric welding; gas generators are used in gas welding. Power supplies may be single-position or multiposition types, stationary installations for continuous, long-term operation, or small, portable units for work of short duration.
A welding transformer is used to match the parameters of the welding circuit and the power supply; it also functions as a voltage regulator. In arc welding, the voltage is regulated mechanically or electrically. In the former case, the distance between the primary and secondary windings is altered. Electrical regulation is accomplished by changing the control currents in supplementary windings, located on the upper and middle field frames of the transformer. In this method, the secondary winding is divided into two sections, one of which is located in the upper window of the transformer. Such a transformer is capable of producing various no-load voltages without a change in the turn ratio; this property is required for welding adjustments. Welding transformers used in resistance welding have a minimum short-circuit resistance and a secondary winding that usually consists of one or two turns. Changes in secondary voltage are achieved by tapping sections of the turns of the primary winding.
A welding generator is a specially designed electric machine—either a DC machine or a machine that operates at higher-than-standard frequencies. Single-position generators are used; they may be general-purpose units, or they may feature drooping external characteristics, which result in a stable welding arc. Welding generators may be of the crossed-field or split-pole type, or they may have a bucking series winding. In a crossed-field welding generator, the short-circuited winding of the armature creates a cross magnetic flux. The drooping characteristics are due to the longitudinal
bucking armature flux. In a generator with a bucking series winding, the external characteristics result from the interaction of the magnetic fluxes of the bucking series winding and the magnetizing parallel winding. Voltage fed to the magnetizing winding is taken from a third brush or from an ind ependent po wer supply..