Metals are so useful that we need to know more about them and the tools that are used to shape, cut, form, and finish them. The following are the basic tools and equipment used in doing metalworks:1. Straightedge. A steel rule used to test the flatness of a workpiece. The edge of the steel rule is placed on the surface of a material and then held up against the light.
2. Outside caliper. This is used to measure the outside dimensions of either a flat or round stock. It may also be used to check the parallelism of surfaces. The setting on the outside caliper may be converted into linear units by measuring the opening with a steel rule.
3. Inside caliper. This is used to measure the diameter of holes or widths of keyways and slots. To convert the inside caliper’s opening into linear units, use a steel rule in the same manner as that of the outside caliper.
4. Hermaphrodite caliper. This consists of two legs, one is like that of a divider and the other one is like the leg of an inside caliper. Hermaphrodite calipers may be used to scribe arcs or in marking layout work.
5. Try-square. This consists of a thick beam sometimes called the stock and a thin blade set at 90° angle. This tool is commonly used to test or “try” the accuracy of work. Many try-squares are gradated on the blade so it may also be used as a rule.
6. Divider. This is similar in construction to calipers except that the legs are straight and terminates in sharp points. These are used for measuring distances between points, transferring measurement from a scale, and scribing circles and arc.s
7. Tape rule. This comes in different lengths but commonly in two metre lengths. They are useful in measuring large dimensions such as lengths of metal bars and width of iron sheets. The flexible metal tape rule is housed into a small metal receptacle and can be pulled out when needed.
8. Vernier caliper. This is a device which measures dimensions more accurately than most other measuring tools and is commonly used in machine shop work.
9. Micrometer. This is used to measure very small dimensions. It may be used to determine the thickness of a a shim or the diameter of a single hair strand.
10. Layout table. This is actually made of granite or cast iron. Granites are considered better than cast iron but are very expensive. For very simple layout work, any plain surface such as an ordinary table top will do.
11. Scribers. These are generally used with a straight edge rule to draw straight lines. These are made of hardened steel and sharpened to a very sharp point. On some scribers, one end is bent to allow marking line in hard-to-reach places.
12. Layout punch. Also commonly known as prick punch. It looks a center punch except that the point is ground to an angle of 30° to 60° and is used to permanently mark the location of layout lines.
13. Center punch. Is practically the same as the prick punch except that the point is ground to an angle of 90°. It is used to mark the location of the centers of holes. The wider the angle of indentation permits a drill bit to start holes accurately.
14. Bench vise. This is the most commonly used tool in benchwork to securel hold small work for sawing, chipping, drilling, reaming, polishing, and tapping operations. Vises are made of heavy cast iron or cast steel. Their sizes are determined by the width of the jaws. When gripping highly polished work or soft materials, jaw caps are used to prevent the work surface from getting marred or damaged. Jaw caps are made of plastic, lead, aluminum, or copper.
15. Hammer. The most commonly used in benchwork are the ballpen, straight peen, and crosspeen hammers. Aside form the three, soft-faced hammers are also extensively used in metalwork. These are used in assembling or disassembling parts so the finished surfaces would not be dented. The faces of soft hammers are made of lead, plastic, rawhide, wood, or copper. These are attached to a steel handle and are generally replaceable.
16. Screwdriver. Instruments designed to drive in and take out screws. The two most common types used in the shop are the standard screwdrivers with a flat blade, and the Philips screwdriver with the crossed tip to fit the recessess of a Philip-head screw. Both of these types are manufactured in various sizes and styles such as the standard, stubby, and offset. An important rule to remember in the use of screwdrivers is to use the right size for the right screw. Too big a size damages the slot of the screw and may even cause the screw to break. Too small a size will dent the screwdriver and also damage the slot of Philips screws.
17. Wrench. Different types of wrenches are used for specific purposes. The name of a wrench is generally derived from its use, shape, or construction. The more common types are as follows:
a. Open end wrench. May be single-ended or double-ended. The opening is generally offset at 150° to permit turning the nut or bolt in a crowded space by flooping or inverting the wrench every single stroke. The double-ended wrench is usually of two opening sizes to accomodate two bolt heads or nut sizes.
b. Box wrench. Is also called the box-end 12 point wrench. This wrench completely surrounds the nut and has 12 equally spaced notches inside. A small rotation of a nut can be affected by shifting the wrench to another notch. It can move as little as 1/12 of a circle or 30°.
c. Socket wrench. Similar to the box wrench but is driven differently by means of a handle provided with a square head which fits on the top end of the socket wrench. The handles may be a rachet or when certain bolts or nuts have to be tightened to a correct degree, a torque handle is used.
d. Adjustable wrench. This has an opening which may be adjusted within a certain range to fit several sizes of nuts or bolt heads. This is particularly useful to repairmen who travel to do servicing jobs, eliminating the need to carry too heavy a load of wrenches. For shopwork, however, this type is not preferable since slippage is more likely to happen if proper adjustments to the bolt head is not attained.
e. Allen wrenches. These are hexagonal L-shaped rods that fit into the slots of allen set screws.
18. Pliers. Are designed for gripping and holding small parts for certain machining operations. They are also modified levers so one can “multiply” gripping pressure with the use of these tools. The different types of pliers are:
a. Slip-joint pliers. Are designed to grip small and big stocks by simply slipping the fulcrum.
b. Side-cutting pliers. These are used mainly for gripping, bending, and cutting small diameter rods or wire. When this pliers is provided with insulated handles, it is also called the electrician’s pliers.
c. Long-nose pliers. These are manufactured either straight or bent. They are usedd for holding very small parts and for positioning in hard-to-get-at places. They are also very useful in making small loops or rings out of wires. This is sometimes called needle-nose pliers. The bent kind is also known as crooked-nose pliers.
d. Diagonal-cutting pliers. Or simply diagonals are useful in cutting, picking up, or putting cotter pins.
e. Vise grip pliers. Provide an extremely strong grip because of the adjustable lever action. The grip pliers can be locked.
19. File. Is a hand cutting tool made of high carboon steel having a series of teeth cut on a flat body or face. The parts of a file are as shown below. Files without handles should not be used. Files are classified according to how the teeth are cut on the face. They may be single cut or double cut. According to the coarseness or size of the cut they are classified as: rough, coarse, bastard, second cut, smooth cut, and dead smooth. According to cross sectional shapes, files are classified as: flat, half-round, square, three-square (triangle), and knife.
20. Hacksaw. This is used in cutting metals and other materials like fiber and plastics. It is composed of a handle, a frame, and a blade.
21. Scraper. This is used to produce a surface more true that can be produced by machining. Scraping is a process of removing small amounts of metal from specific areas to produce an accurate surface. It is a long and tedious process. Scrapers are made of high grade hardened, and tempered tool steel. Carbides are sometimes added to the tips to make them last longer.
22. Chisel. Is the simplest form of cutting tool. It is made of heat-treated steel with the cutting edge shaped differently for various chipping requirements. The following are the most commonly used chisels in the metalworks shop:
a. Flat chisel. Is used for cutting and chipping metals and for splitting nuts, bolt heads, and rivets. The blade of the flat chisel is ground to an angle of 60° to 70°.
b. Diamond-point chisel. Is used for clearing out corners or correcting errors while drilling in steel plates. It is ground to a square cross section end and provided with a cutting edge at one corner.
c. Cape chisel. Has a narrow cutting edge and is used in cutting narrow grooves, splints, or keyways.
d. Round nose chisel. The tip of this chisel is round and is used in making half round grooves and channels. It may also be used for moving holes which have been inaccurately started.
These are called cold chisels because they are designed to cut metals at room temperature. There are special chisels described as hot chisels which are used to cut or chip while the metal being worked on is red hot. These chisels are provided with a long handle to keep the operator’s hand away from the hot metal.
23. Snips. Are tools necessary in the metalworks shop especially when working with metal sheets that are very thin (1/16 of an inch thick). The snips are generally called tinner snips as these are the main tools of a tinsmith. The different types of snips are:
a. Straight snip. Is used in cutting along a straight line on a metal sheet, plastic, rubber, and other materials. They are made in various sizes with cutting edges from two to five inches long. The handles are generally plastic coated.
b. Hawk-bill snip. Has narrow, slightly curved blades. It may also be used to cut a straight edge but is most effective in cutting along inside curves.
c. Aviation snip. Has short cutting blades and two fulcrums for a greater mechanical advantage. It may be used for cutting straight edges or curves but is most effective in cutting long outside curves.
24. Hand drills. Are tools used for drilling small holes through metals, wood, or plastic. It consists of a shank which is attached to a toothed wheel with a handle. The toothed wheel or gear turns another toothed wheel and carries the shaft which holds the chuck and the drill bit.
25. Twist drill. This is a cutting tool consisting of a steel rod with two flutes running around its body, the point of which is ground so that cutting edges are formed. Twist drills are manufactured from forged steel. They are available in available in a variety of sizes from a small as 1/32 to as big as two inches in diameter. They are made with neither a straight or tapered shanks. Small twist drills are generally straight while the bigger ones tapered.
26. Reamer. Is made of special steel with shallow cutting edges around its entire length. It is used to smoothen the surface of the hole made by a drill to finish it to a standard size.