- - AGRICULTURE CORE CURRICULUM - - (CLF2000) Advanced Core Cluster: AGRICULTURE MECHANICS (CLF2350) Unit Title: Metalworking ___________________________________________________________________________ (CLF2351) Topic: - Metalworking Safety Time Year(s) 1 Hour 1 / 2 / 3 / 4 ___________________________________________________________________________ Topic Objectives: Upon completion of this lesson the student will be able to: Learning Outcome # (H-10) - Operate power tools such as drills and saws after completing appropriate safety tests. Special Materials and Equipment: Select and have available for students ten common metalworking tools to see and handle. Provide several power tools for demonstration and student inspection also. References: Burke, Stanley R., & Wakeman, T. J. (1990). MODERN AGRICULTURAL MECHANICS (2nd ed.). Danville, IL: Interstate Publishers. Phipps, Lloyd J., & Reynolds, Carl L. (1990). MECHANICS IN AGRICULTURE (4th ed.). Danville, IL: Interstate Publishers. Evaluation: Quiz by instructor and demonstration by students of safe handling and use of ten power and hand tools used in metalworking. TOPIC PRESENTATION: Metalworking Safety SAFETY IN COLD METALWORK* Safety Practices for Working Cold Metal When working cold metal, observe the following safety practices. When performing cold metalwork, you should know and observe the general as well as the specific safety practices for the hand tools power tools, and portable power tools used. 1. Keep the work area clean. Wipe up oil and grease spills immediately to prevent injuries caused by slipping and falling. Keep paths to exits clear. 2. Use eye protection. When doing cold metalwork, wear approved safety glasses or a face shield. 3. Store rags safely. Store oily and greasy rags in a fireproof metal container to prevent the spreading of spontaneous fires. 4. Use the correct lifting method. Serious injury may result from straining due to incorrect lifting. Lift heavey objects with the leg muscles, not the back muscles. When lifting heavy objects, obtain assistance. 5. Use proper tools. Always use the proper-sized tools and equipment for the job. 6. Obtain the instructor's permission. Use equipment only with the instructor's permission. Notify the instructor immediately if you are injured. 7. Wear proper clothing. Wear clothing that is not loose or bulky and wear hard-toed shoes with non-skid soles. 8. Ground electrical equipment. Each electrical tool should be equipped with a three-prong plug and plugged into a grounded three-hole receptacle. When used outside, portable tools should be connected to ground fault circuit interrupter outlets. 9. Restrain long hair. Restrain excessively long hair with a band or cap to keep hair from getting entangled in machines. When using a drill or drill press, be extremely careful with long hair. 10. Secure stock. Be certain that stock to be cut, filed, or chiseled is securely fastened in a vise or by clamps to prevent tools from slipping. 11. Mount holding devices securely. Mount vises, anvils, and clamps securely for cold metalwork. Safety Practices for Using Hand Tools in Cold Metalwork* Before studying the specific safety practices for using hand tools, review the cold metalwork general safety practices. 1. Provide handles for files. Handles on files reduce the possibility of a puncture wound from the file tang. 2. Clean files properly. Use a file card to remove metal from a file. Never use your hands. 3. Never use a file for prying. Excessive pressure on the file while you are prying may cause it to break. 4. Avoid tools with mushroomed heads. Small particles of metal from the mushroomed heads of punches or cold chisels may break off and cause injury. 5. Keep cutting-edge tools sharp. Dull chisels are dangerous as they require excessive pressure and hammering to make them cut. 6. Cut away from bystanders. To avoid hitting bystanders with flying chips, chip and cut in the opposite direction. 7. Carry sharp tools properly. All sharp-edged tools and chisels should be carried with the cutting edge down. Never carry sharp tools in a pocket. 8. Avoid hammers with loose heads. A loose hammer head is dangerous as it may fly off during use and cause injury. 9. Use the correct hammer for the job. Never use a carpenter's hammer to strike punches or chisels. 10. Watch your fingers. Take special care when you are hammering so that you strike the object, not your fingers. 11. Use a wrench of the proper size. Wrenches that fit improperly may slip and cause injury. Adjust wrenches to fit snugly on a nut to avoid slipping. 12. Pull on wrenches-do not push. Pushing on a wrench is dangerous because the nut may break loose unexpectedly, thus causing skinned or cut knuckles. Always pull with the force on the stationary side of an adjustable wrench. 13. Never extend handles. Handles that are extended with a pipe may break unexpectedly and thus cause injury. 14. Never strike wrenches with hammers. Striking a wrench with a hammer may cause the wrench to bend or break. 15. Use pliers properly. Use pliers for their intended purposes only. Never use pliers in place of a wrench. 16. Do not use damaged wrenches. Because wrenches with badly worn, chewed, or spread opening are likely to slip, they should not be used. 17. Never throw tools. Never toss tools to another worker. The tools may be damaged or the worker may be injured. 18. Keep tools clean. Keep tools and hands clean and free of grease and oil so that you can grip tools properly. 19. Store tools properly. Never leave tools where they may fall, be stepped on, or bumped into. Store tools in a safe location to prevent injury to others and to prevent tools from being damaged. Safety Practices for Using Metal-cutting Band Saws and Power Hack Saws* Before studying the specific safety practices for using metal-cutting band saws and power hack saws, study the stationary power tools general safety practices...[reproduced in CLF2100] 1. Secure metal in the saw vice. Slipping metal can cause blade breakage and injury. 2. Clean chips from saw properly. Use a brush to clean metal chips from the saw. Never use your hand! Do not attempt to clean the saw while it is running. 3. Handle cut metal carefully. Newly cut pieces of metal containing burrs can cause serious cuts. When handling metal with burrs, wear gloves. Remove burrs from metal as soon as possible. 4. Support long stock. To prevent long pieces of metal from falling, always use a stand to support long stock. 5. Use proper holding devices. Secure irregularly shaped objects in a holding device, such as a V-block for round stock and a drill vise for small objects. 6. Always start a new blade in a new kerf. Because of the set in the new saw blade, the kerf is wider than the kerf made by a used blade. Starting a new saw in an old kerf will ruin the set and may break the blade. Safety Practices for Using Drill Presses* 1. Wear industrial-quality eye protection. Wear safety glasses which are approved and meet the Z87.1 standards. 2. Use good-quality bits. For the safest and most efficient operation, use only straight, sharp, burr, and nick-free bits. 3. Tighten the bit securely in the drill chuck. Use a chuck wrench to tighten the bit in the chuck. Be certain to remove the chuck wrench after the bit has been tightened. 4. Anchor the drill press. An unanchored drill press is unstable and easily turned over. 5. Use proper holding devices. Secure irregularly shaped objects in a holding device, such as a V-block for round stock and a drill vise for small objects. 6. Use a cleaning brush. Remove chips with a brush, not your hands. Cuttings are sharp, and splinters or cuts could result. 7. Avoid seizing. Relieve pressure on the drill just before it breaks through the stock to prevent it from binding, causing the stock to rotate or the drill bit to break. 8. Support the ends of long stock. This will keep undue pressure from being exerted on the drill. 9. Never attempt to stop revolving stock with your hands! Do not attempt to stop a revolving piece of stock in which the drill is caught. Cut off the power and then free the bit. 10. Remove the bit from the chuck. After the drilling is completed, remove the bit from the chuck and then place it in its designated place. 11. Attach the vise permanently. Attach the vise to the drill table in such a way that it is permanent but pivotable. 12. When using the drill press, do not wear baggy clothes or leave long hair loose. SAFETY IN HOT METALWORK* Safety Practices for Working Hot Metal Observe the following general safety practices for working hot metal. 1. Obtain the instructor's permission. Before using any tool or machine, you must obtain the instructor's permission. The instructor must be aware of all laboratory activities and will know if the equipment is in safe working order. 2. Wear industrial-quality eye protection. To protect the eyes from sparks and metal chips, wear approved eye protection. 3. Wear proper clothing. To protect against burns, wear clothing such as coveralls, high-top shoes, leather aprons, and leather gloves. Remove all paper from pockets, and wear cuffless pants. 4. Protect hair and scalp. To protect the hair and scalp, restrain excessively long hair and wear a cap. 5. Know emergency procedures. In the event of an emergency, all students involved in or observing the emergency should call for help immediately as well as assist in correcting the situation. You should know the location of fire extinguishers and fire blankets and how to use them. You should also know the approved procedure for exiting the laboratory. 6. Report all injuries. Report all injuries or accidents to the instructor immediately, no matter how slight. The instructor will secure medical help. 7. Keep work area and tools clean. Dirty, greasy, and oily tools and floors can cause accidents. Clean and put away all unneeded tools and materials. Clean up oil spills and scrap metal from the floor and equipment. 8. Use correct tools. Always use the right size tool and only for its intended purpose. Use tongs or pliers for carrying hot metal. 9. Avoid horseplay and loud talk. Loud talking as well as pushing, running, and scuffling while working with hot metal can cause serious accidents. Keep your mind on your work. 10. Work in a well-ventilated area. Fumes and intense heat are part of hot metalwork and require that work be done outdoors or in a forced-ventilated area. This is especially true when you are working with zinc (galvanized iron or pipe), cadmium, or beryllium. 11. Use correct lifting methods. When lifting heavy objects, obtain help. Lift with the legs and not the back. Straining to lift heavy objects can cause serious injury. 12. Store hot metal in a safe place. To avoid the possibility of accidental burns, keep hot metal in a safe place until it cools. Do not offer hot stock to the instructor for inspection. 13. Never touch suspected hot metal. Test metal with moistened finger tips before actually touching it. Use tongs or pliers for handling hot metal. 14. Turn off heat source before leaving work area. Before leaving the laboratory or work station, make certain the heat source is shut off and cool. 15. Avoid using hot metalwork around flammable material. Do not perform hot metalwork on wood floors or near flammable material. Never work on containers that have been used for storage of combustible material without first having cleaned and safeguarded them. 16. Protect welder cables and hoses when you are hot metalworking. Keep cables and hoses from coming in contact with hot metal and sharp objects. Never point a flame at cables or hoses. 17. Use warm water instead of quenching oil for quenching. Quenching oil is easily confused with other oils. It is difficult to identify. If quenching oil is used, take it from new, previously unopened cans. Safety Practices for Using a Gas Furnace* Before studying the specific safety practices for using a gas furnace, review the hot metalwork general safety practices. 1. Check for leaking gas. Before firing the furnace, check all the connections with soapy water for possible leaks. This will prevent a possible fire or explosion. 2. Light the furnace correctly. When firing the furnace, keep the doors open and stand to one side. Otherwise ignition may cause the doors to fly open. 3. Use tongs. When removing metal from a hot furnace, always use tongs that fit the stock. 4. Use a safeguard system. A gas furnace should, equipped with a safeguard system such as the ultra-violet combustion safeguard system. 5. Use a flint lighter. When lighting a manually ignited gas furnace, always use a flint lighter. Never use matches. Safety Practices for Using an Electric Furnace* Before studying the specific safety practices for using an electric furnace, review the hot metalwork general safety practices. 1. Avoid electrical shock. Be certain the furnace is grounded and that the electric lead cable is properly insulated. 2. Check grating for scale. Before using the electric furnace, make sure there is no scale on the grating. Scale can short and burn out the coils. 3. Keep the door closed. When the furnace is not in use or is left unattended, make certain that the door is closed. 4. Use tongs. When removing hot metal from the furnace, always use tongs that fit the stock. SAFETY IN SOLDERING, BRAZING, AND SHEET METALWORK* Before studying the specific safety practices for soldering, brazing, and sheet metalwork, review the hot metalwork general safety practices. Safety Practices for Using a 14-Oz. Propane Torch 1. Wear industrial-quality safety glasses. Wear safety glasses to protect your eyes from spatter and fumes. 2. Use a flint lighter-not matches-to light the propane torch. Matches will bring your fingers too close to the flame. 3. Keep the propane tip pointed away from your body. 4. While using propane torches or cylinders, do not smoke or allow others to smoke because of the potential fire hazard. 5. Turn the propane nozzle off properly. Close the propane tank valve snugly, but do not overtighten. Because the propane tank valve is made of copper, excess pressure will strip the threads. The nozzle should be turned off when there is no flame to prevent propane from escaping and filling the work area with gas. 6. Attach the propane nozzle correctly. Screw on the nozzle tightly to avoid leakage and possible explosion. 7. Remove the propane nozzle from the canister when finished. When you are finished for the day, remove the nozzle from the canister to prevent any gas from escaping. 8. Do not refill propane canisters. Only trained persons should refill canisters. The contents are under pressure and could explode. 9. Dispose of empty propane canisters properly. Do not incinerate empty canisters because they will explode. Safety Practice for Using Electric Soldering Irons* 1. Handle the soldering iron carefully. To prevent burns and fire, handle the electric soldering iron with care. 2. Inspect soldering iron cords and plugs regularly. Always inspect the cord of an electric soldering iron for poor insulation before you use it. Unplug the cord when you are finished or interrupted. 3. Do not lay down a hot soldering iron on wood, paint solvents, or other combustible materials. 4. Never solder in a damp area. Stand on a dry board when you are soldering if the floor or ground is damp or wet. 5. Store soldering iron safely. Allow copper to cool before you store the iron. SAFETY PRACTICES FOR USING A COAL FORGE AND AN ANVIL* Before studying the specific safety practices for using a coal forge and an anvil, review the hot metalwork general safety practices. 1. Secure the anvil. Be certain the anvil is securely anchored so that it will not give under pressure and fall. 2. Keep the anvil's face clean. Keep the face of the anvil dry and free of scale. 3. Strike the anvil properly. Never strike the face of the anvil with a hammer or another object that is as hard as the anvil. 4. Cut metal safely. When cutting hot metal on an anvil, use a handled hot metal cutter and the cutting block or hardy. 5. Protect others. When working with metal on an anvil, warn observers and bystanders to keep back, as metal chips may fly. 6. Keep tools in good condition. Keep forge tools sharp and free of mushroomed heads. Be certain that handles are tight in forge hammers. 7. Use correct tongs. When handling hot metal, always use tongs that fit the stock. _____________________ * Reprinted by permission of Interstate Publishers, Inc., from MODERN AGRICULTURAL MECHANICS, 2nd ed., by Stanley R. Burke and T. J. Wakeman. Copyright 1992 by Interstate Publishers, Inc. __________________________________________________________ ACTIVITY: 1. Draw a floor plan of the shop indicating the power tool positions, bench locations, and doors; show all safety equipment located in the shop. 2. Develop a list of shop tools used in metalworking for a home shop. Price the tools from the local hardware store or a catalog. __________________________________________________________ 7/17/91 YNJ/tf #%&C