Welding Processes and Fundamentals Series Shielded Metal Arc Welding. Understand how shielded metal arc welding (SMAW) systems work.

Transcription

1 Welding Processes and Fundamentals Series Shielded Metal Arc Welding Introduction This guide provides information to help you get the most out of the Shopware Shielded Metal Arc Welding program of the Welding Processes and Fundamentals series. As the title suggests, Shielded Metal Arc Welding introduces this popular fabrication and repair process, covers the basic setup procedures involved, and illustrates basic shielded metal arc welding techniques. This video program also describes the potential dangers that shielded metal arc welding poses, along with the steps you should take to ensure welding safety. Learning Objectives After viewing the program, students will be able to: Understand how shielded metal arc welding (SMAW) systems work. Identify the potential dangers welding presents to trade professionals. Understand how an SMAW system is set up for use. Understand how SMAW systems are used for repair and fabrication. 1

2 Program Summary This program is designed to give viewers a foundation in shielded metal arc welding (SMAW) systems, their setup, and their proper use. Sections 1 and 2 of this program introduce the SMAW process and examine the physical components of a typical SMAW system. Section 3 examines the fundamentals that every welder should know about the various welding rods that welders use. After this, a comprehensive discussion of personal protective equipment (PPE), such as appropriate helmets, gloves, and clothing, is undertaken in Section 4. The remaining sections cover the setup of a typical SMAW system and proper usage. In particular, students are shown proper SMAW techniques and the attributes of high-quality welds. Also shown are several different arrangements of the base metals being joined. This includes different horizontal, vertical, and other configurations and the types of welding beads and passes that are most appropriate for each. The Shielded Metal Arc Welding program ends with a short conclusion and words of encouragement for student welders. Correlates to all National CTE Organizational Standards (including the provisions of the Perkins Act). Main Topics Section 1: Introduction to Shielded Metal Arc Welding This section introduces the viewer to shielded metal arc welding (SMAW) and explains how the electric arc between the electrode and base metal creates molten metal that the welder uses to join base metals together. This segment also explains how the electrode rods are coated with flux engineered to emit shielding gas to protect the molten weld puddle from atmospheric contamination. Section 2: Components of a Shielded Metal Arc Welding System In this section, viewers learn about the technology and use of typical SMAW systems and practical considerations when using them. In addition, students learn about the different types of SMAW welders, the effects of straight and reverse current polarity, and details about types of welding cables. Section 3: Choosing the Correct Welding Rod A critical part of the SMAW welding process is understanding the differences between the various types of arc welding rods and knowing how to choose the best one for different applications. This section reviews the basic parameters involved when choosing welding rods and profiles a few of the industry s more common examples. Section 4: Safe Welding Environment and Protective Equipment This section covers the steps necessary to ensure that the welding environment is safe for the welder and others in the work area. This segment also introduces the student to the personal protective equipment (PPE) that should be worn whenever cutting or welding is practiced. 2

3 Section 5: Setting Up SMAW for Use Here the student is shown the step-by-step process of setting up an SMAW welding system for use. Discussed is the careful examination of equipment before use, the proper settings on the SMAW welder, and ways that the welding rods can be mounted in the electrode holder. Section 6: Laying a Bead Section 6 goes through the process of creating high-quality welds with SMAW equipment. In the trade, this is often referred to as laying a bead. The many details that student welders should learn when welding and laying beads are covered. Starting with the best ways to strike an arc, students are shown drag and push techniques and the proper traveling motions used. Section 7: Reading the Bead Good welders must be able to look at welds and beads and be able to judge their quality. This is often called reading the bead. When welds are created that are of poor quality, welders must know the parameters that caused this, such as voltage, travel speed, etc. This section covers such details and shows images of weld beads that are of poor quality. Special emphasis is paid to monitoring the welding process and what steps to take if anomalies occur. Examples of this include too much spatter, porosity, poor penetration, and wavy beads. Section 8: Advanced Welding Techniques Welders must join pieces of metal in many different configurations and alignments. Each of these generally requires a specific approach for high-quality welds. A review of the nomenclature of the different types of welds is undertaken as are topics such as root passes, fill passes, and horizontal, vertical, and overhead locations. Section 9: Conclusion This closing section shares safety tips for all trade professionals involved in SMAW along with wishes for continued success in the subject area. Fast Facts Because of the versatility of the process and the simplicity of its equipment and operation, shielded metal arc welding is one of the world s most popular welding processes. It is popular in the repair trades and for hobbyists because of its simplicity and the low cost of the welding equipment and consumables. SMAW is one of the oldest welding techniques. In 1890 C. L. Coffin received U.S. Patent 428,459 for his arc welding method that utilized a consumable metal electrode. 3

4 The Occupational Safety and Health Administration (OSHA), of the U.S. Department of Labor, states that welding, cutting, and brazing are hazardous activities posing safety and health risks to more than 500,000 workers in a wide variety of industries. Mild steel melts at about 2750 degrees F depending on the carbon content. Arc welding can reach degrees F. Butane lighters can explode in welders pockets. If molten spatter from welding lands on a plastic lighter, it can instantly melt and penetrate the butane container, causing the butane gas to explode with the force of a small stick of dynamite. SMAW welding is the clear choice when welding outdoors because of its lower sensitivity to wind and drafts over gas shielded welding processes. The brightness and danger of the light emitted during welding and cutting varies with the type of metal being welded and the welding process utilized. If skin is exposed to intense radiation energy, such as that from an electric arc, it can result in skin burns, premature aging, and ultimately skin cancer. Many cutting and welding processes produce toxic fumes: gases and airborne particulates that can be harmful if inhaled. Welders should not disregard the danger of these fumes. The presence of oily rags in the welding environment is a safety hazard. Sparks can travel feet and smolder in oily rags for hours before actual combustion (flames) occurs. Vocabulary Terms Amperage The amount of current flowing in a circuit, which is measured in amperes. Arc Gap The distance from the tip of the welding electrode and the base metal; 1/8 th inch is a typical arc gap distance used in SMAW welding. Backhand Technique Moving the electrode along the workpiece opposite the direction of the welding bead. Cap Pass The final welding pass on top of deeper welds. Combustible A substance that readily ignites and burns when exposed to flames and sparks. 4

5 Confined Space Permit A special permit issued by safety organizations such as OSHA that specifies the requirements that must be met in order for welding or other processes to be executed in a confined space. Constant Voltage Welding using a voltage that varies slightly with changes in current. Constant voltage, (CV) is often used for gas metal arc welding (GMAW) and flux-cored arc welding (FCAW). DCEP An abbreviation for direct current electrode positive. DCEP is another way of expressing direct current reverse polarity (DCRP). DCRP Acronym for direct current reverse polarity. DCSP Acronym for direct current straight polarity. Duty Cycle The term duty cycle refers to the amount of time during a 10-minute period that a piece of welding equipment can be used. For example, the Miller Thunderbolt XL creates a 200 amp DC output at 20 percent duty cycle. This means it can weld continuously at 200 amps for two minutes and then must cool for eight minutes to prevent overheating. E-6010 A popular, general-purpose welding rod. Flux A nonmetallic material used to protect the weld puddle and solid metal from atmospheric contamination. In SMAW, flux material is contained in the coating around the electrode. Fill Pass After the first welding pass (the root pass) is performed in a deep weld, the subsequent passes are often referred to as fill passes. This is because they essentially provide the fill for the rest of the weld. Forehand Technique Moving the electrode along the workpiece in the direction of the welding bead. Inert Gas A nonreactive gas used during cutting and welding to shield molten metals from external contaminants. Oxidized Oxidation is the process whereby oxygen combines with a metal surface and a new compound is created. In the case of iron and steel, oxidation creates iron oxide, which is most commonly called rust. Most metals oxidize to some degree, with iron and steel doing so relatively quickly. Particulates Tiny particles of solid or liquid matter suspended in a gas or liquid. In welding and cutting, particulates are often emitted and tend to be hazardous to breathe. 5

6 Porosity Cavity-type discontinuities or bubbles formed by gas entrapment during solidification of the weld metal. Porous welds are considered low-quality welds, and welders should be familiar with the various factors that can lead to them. PPE Acromym for personal protective equipment, which refers to professional welding helmets, gloves, boots, and other appropriate clothing and gear that is used when welding and cutting. Push Welding An SMAW technique whereby the welder pushes the puddle along when laying a bead, resulting in the arc being on top of the weld bead. Root Pass A root pass is usually the first welding pass that is taken in a large weld. After the root pass has been accomplished, filler welds are typically laid on top. Shielding Gas An inert or semi-inert gas used in many welding processes. Inert gases are generally used to shield molten metals so that atmospheric contaminants do not enter. Slag The residue left on an SMAW weld bead. This slag covering comes from the flux and must be chipped away. SMAW Acronym for shielded metal arc welding. Spatter Under certain conditions, arc welding scatters out tiny droplets of molten steel. These metal droplets are messy, dangerous, wasteful and hazardous to operators. Spatter also creates rough and unsightly welds that are very difficult and time-consuming to remove. Tacking Tacking is a process whereby the pieces of metal that are to be fastened together are welded in a number of small places along the full welding path. This process holds the entire structure steady and in the correct dimensional form during the full welding process. Tie-in The term used for restarting a weld so that it is continuous. This is an important concept because welds that are paused for any reason must be tied-in properly or the weld quality can be compromised. 6

7 Pre-Program Discussion Questions 1. What exactly is welding? What are welders trying to accomplish? 2. Are there different ways to weld metals? Explain and describe at least one method that you know about. 3. What is shielded metal arc welding (SMAW)? How does it work? 4. Why is it so important to understand the risks and take proper precautions when using SMAW equipment? 5. SMAW doesn t require a shielding gas. Why is this? 6. How can most of the risk of injury be eliminated by using the proper personal protective equipment (PPE)? 7. Which trades are likely to require welding tasks? 8. What are the different types of welds that professional welders may be called upon to perform? 9. What types of dangers might welders experience on the job beyond those of dealing with the welding equipment itself (e.g., the welding environment, confined spaces, standing water)? Post-Program Discussion Questions 1. In basic terms, describe how an SMAW system works. 2. Describe the various types of PPE that welders should use. 3. Is inspecting the welding equipment before using absolutely necessary? Why? 4. What are the basic steps to setting up an SMAW system for use? 5. How does a welder know what settings to use initially when setting up an SMAW system? 6. Describe a few of the characteristics that distinguish certain welding rod types from each other. 7. In what ways does OSHA protect welders and cutters on the job? Why are these workplace regulations important? 8. Describe the differences between the push and pull methods used when laying beads with SMAW. 9. What kinds of problems might a welder see with weld quality? What would one do to correct them? 7

8 Suggested Student Projects Trade Professions Involving Welding Instruct students to research a variety of specific trade professions that involve welding. Each student selects one profession to research in order to learn how welding is used in this specific trade and writes a one-page description. The class can then compile the descriptions into a vocational handbook. This handbook can be converted into PDF form and made downloadable on the school website. A Pictorial View of Welding Safety Practices Students review welding safety images found on the Internet and then create posters illustrating and spelling out the safety tips involved in the trade. The posters might be created for workplace safety, a training program, or as a checklist for trade professionals as they gear up for a job. Alternatively the images can be compiled into a PowerPoint presentation for class use. Welding Safety Training Students work in small groups to create short safety training classes that welding professionals might attend. Encourage students to use a variety of presentation techniques (visuals, props, role plays, dramatization, etc.). The sessions can be captured on video and uploaded to YouTube. Face-to-Face To learn more about welding, students can interview various trade professionals who either work as welders or have welding and cutting as part of their work. These interviews can be shared with the class in the form of a report or PowerPoint presentation or can even be video-captured for YouTube. Guest Lecturing Students can arrange for trade professionals to visit the classroom and discuss the welding trade. Professionals can be asked what they like about the trade and exciting projects they may have worked on. They can also be encouraged to share specific experiences with the class, such as situations when things went wrong. 8

9 Assessment Questions Q1: Shielded metal arc welding is often referred to as: a) Stick welding b) SMAW c) MIG welding d) Both a) and b) e) Both b) and c) Q2: Where does the shielding gas in SMAW come from? a) A tank of shielding gas b) The welding supply store c) The arc welding rod d) None of the above Q3: Which article of PPE (personal protective equipment) is the least significant to consider when welding or cutting metals? a) Long-sleeved cotton shirts and pants with no cuffs b) Gauntlet-style leather gloves c) Extra-thick helmets to protect the welder from concussions d) Steel-toed work boots e) Professional welding jacket Q4: Which activity is least important for ensuring a safe welding environment? a) Maintaining good ventilation b) Ensuring room light switches are easy to access c) Eliminating paper, rags, and other combustible debris nearby d) Clearing the floor and welding structure (bench, tables) of unnecessary cables and hoses Q5: Some SMAW welding rods are optimized for the following parameters: a) Welding position (flat, vertical, overhead) b) Base metal penetration c) Pleasant smells during welding d) Both a) and b) 9

10 Q6: There are many settings on an SMAW system. Parameters such as AC or DC current, voltage, and reverse or straight polarity must all be adjusted according to the welding job. These settings should come from: a) Your classmates b) Manufacturer s recommendations c) Charts on the welding machine d) Your welding instructor only e) Both b) and c) Q7: Why are automatic-darkening goggles and helmets so popular? a) They automatically protect one s eyes b) They can be personalized in many colors c) They make welding workflow very efficient d) Both a) and c) Q8: Protecting against welding-generated toxic fumes is important because: a) Breathing toxic fumes can affect your welding technique b) Toxic fumes can cause short-term health problems c) Toxic fumes can cause long-term health problems d) Both b) and c) e) All of the above Q9: Forehand welding refers to a method of welding whereby: a) The welder pushes the puddle b) The electrode gun is held like a tennis racket c) The welder drags the puddle d) Both a) and c) Q10: If a GMAW weld is showing excessive spatter, what do you do? a) Slow down the electrode gun travel b) Reduce the machine voltage c) Increase the gas pressure d) All of the above Q11: Why is it especially important to cover all exposed flesh when arc welding? a) Hot sparks can tickle when they strike you b) It will shield your skin from infrared (IR) light c) It will shield your skin from ultraviolet (UV) light d) Both b) and c) 10

11 Assessment Questions Answer Key Q1: Shielded metal arc welding is often referred to as: a) Stick welding b) SMAW c) MIG welding d) Both a) and b) e) Both b) and c) Answer: d) When shielded metal arc welding was first developed (over 100 years ago) it was often called arc welding or stick welding. Because there are many variations of arc welding today, the American Welding Society designated this type of welding utilizing consumable, flux-coated electrodes as shielded metal arc welding, or SMAW. Today SMAW is the formal term, but in the trade, the term stick welding is often used. Q2: Where does the shielding gas in SMAW come from? a) A tank of shielding gas b) The welding supply store c) The arc welding rod d) None of the above Answer: c) Some welding systems use tanks to provide a flow of inert gas that protects the molten weld from atmospheric contamination. This is not the case in SMAW welding, but there is an inert gas involved. This gas comes from the flux on the consumable coating on the welding electrode. When melted by the intense heat of the electric arc, the flux coating releases inert gases and a molten slag to protect the weld. Q3: Which article of PPE (personal protective equipment) is the least significant to consider when welding or cutting metals? a) Long-sleeved cotton shirts and pants with no cuffs b) Gauntlet-style leather gloves c) Extra-thick helmets d) Steel-toed work boots e) Professional welding jacket Answer: c) This question is designed to allow the instructor to review the topic of PPE (personal protective equipment) with students. The many potential hazards of welding and cutting can be mitigated by use of the proper PPE at all times. This means long-sleeved cotton shirts and pants with no cuffs, professional gauntlet-styled leather welding gloves, professionally designed welding helmets, welding filters, rugged work boots (preferably steel-toed), and a professional welding jacket. The least significant item is arguably c). Welding helmets are not primarily designed to prevent welders from 11

12 accidental blows due to falling debris and other objects. They are specifically designed to protect the welder s eyes from the intensity of the electric welding arc, and the flesh on the welder s head and neck from the IR/UV rays that are emitted during welding. Q4: Which activity is least important for ensuring a safe welding environment? a) Maintaining good ventilation b) Ensuring room light switches are easy to access c) Eliminating paper, rags, and other combustible debris nearby d) Clearing the floor and welding structure (bench, tables) of unnecessary cables and hoses Answer: b) This question is designed to allow the instructor to review the topic of hazards in the welding environment. Clearing hazards from the welding area can mitigate many of the potential dangers of welding and cutting. General hazards include paper, rags, and other combustibles, while tripping hazards include hoses, cables, and metal parts. In addition, when using electric tools such as arc welders and plasma cutters, moisture and standing water must be avoided. It is also important to maintain good ventilation of the welding environment, especially in confined areas. Q5: Some SMAW welding rods are optimized for the following parameters: a) Welding position (flat, vertical, overhead) b) Base metal penetration c) Pleasant smells during welding d) Both a) and b) Answer: d) This question allows for a discussion of not only the correct responses a) and b) above but all the parameters that should be taken into account when choosing welding rods. A common rod is E-6010, and students should understand that this rod is good for most welding positions because it solidifies quickly and is tolerant of base metal conditions like oxidation (rust), paint, and other surface contaminants. Q6: There are many settings on an SMAW system. Parameters such as AC or DC current, voltage, and reverse or straight polarity must all be adjusted according to the welding job. These settings should come from: a) Your classmates b) Manufacturer s recommendations c) Charts on the welding machine d) Your welding instructor only e) Both b) and c) Answer: e) There are many parameters that need to be set on an SMAW system before use. The manufacturers of the various consumables and equipment will usually provide documentation that can assist with these settings. In addition, most manufacturers of the SMAW machines have a permanent label on those machines that give suggested settings for various applications. 12

13 Q7: Why are automatic-darkening goggles and helmets so popular? a) They automatically protect one s eyes b) They can be personalized in many colors c) They make welding workflow very efficient d) Both a) and c) Answer: d) Automatic-darkening welding goggles and helmets allow you to look at the parts to be welded or cut through a very low-shade lens and with the helmet down over your face. Then, a light sensor on the helmet instantly detects when you first light a torch or plasma cutter, and the lens instantly goes to a preset darkness to protect your vision. One of the main reasons that auto-darkening helmets are so popular is that they can save a lot of time otherwise spent flipping one s goggles and helmet up and down during workflow, which makes the welding process more efficient. Q8: Protecting against welding-generated toxic fumes is important because: a) Breathing toxic fumes can affect your welding technique b) Toxic fumes can cause short-term health problems c) Toxic fumes can cause long-term health problems d) Both b) and c) e) All of the above Answer: d) Workers should consider the type of base metal that is being welded or cut, e.g., iron, steel, aluminum, or zinc. They should also know about any coatings on the base metal, like zinc on steel for rust protection. When heated during welding and cutting, materials can be burnt or vaporized. This may create toxic fumes, which can cause short- and long-term heath effects. Workers should always verify that plenty of ventilation exists whenever welding or cutting is practiced. Q9: Forehand welding refers to a method of welding whereby: a) The welder pushes the puddle b) The electrode gun is held like a tennis racket c) The welder drags the puddle d) Both a) and c) Answer: a) Forehand welding is a technique whereby the welder leans the welding gun slightly backward and pushes the molten puddle along. Forehand welding typically generates less heat in the base metal and thus less penetration than other techniques. 13

14 Q10: If an SMAW weld is showing excessive spatter, what do you do? a) Slow down the electrode gun travel b) Reduce the machine voltage c) Increase the gas pressure d) All of the above Answer: d) Each of the previous parameters affects the quality of the weld in a way that can contribute to excessive spatter. It is important to recognize when spatter is occurring during welding and to take immediate action. Spattering not only presents a safety hazard; it is also poor welding technique that is difficult to clean after the welds are completed. Q11: Why is it especially important to cover all exposed flesh when arc welding? a) Hot sparks can tickle when they strike you b) It will shield your skin from infrared (IR) light c) It will shield your skin from ultraviolet (UV) light d) Both b) and c) Answer: d) Arc welding creates a very powerful light source that can emit not only visible light but IR and UV rays. UV rays in particular are damaging to skin tissues and can create painful sunburn to exposed flesh. 14

15 Additional Resources American Welding Society The American Welding Society (AWS), founded in 1919, is a nonprofit organization with a goal to advance the science and technology of welding and related joining disciplines. Their website offers a great deal of welding safety and instructional material. Lincoln Electric In business over 115 years, Lincoln Electric is one of the world s foremost welding equipment and supply companies. They have an extensive library of resources for welders of varied experience, from seasoned professionals to students learning the trade. Miller Welding Miller is one of the largest manufacturers of welding and cutting equipment and has an extensive collection of online resources for welders at all stages in their careers. NASD: National Ag Safety Database The National Ag Safety Database (NASD) is a collection of publications about agricultural safety and health. NASD contains many kinds of informational materials, including fact sheets, training materials, PowerPoint presentations, video references, and complete online videos. Search on welding safety. United States Department of Labor, Occupational Safety and Health Administration Created by Congress in 1970, the Occupational Safety and Health Administration (OSHA) assures safe and healthful working conditions for working men and women by setting and enforcing standards and by providing training, outreach, education, and assistance. They have an extensive collection of welding safety documents and forms. Weld Guru Weld Guru is a private site designed to aggregate content related to welding and cutting. Many helpful, informative, and easy-to-read documents can be found here. Welding Information Center The Welding Information Center is a website sponsored by current and former manufacturers and distributors of welding rods. The purpose of the site is to educate the public by gathering and providing access in one place to notable publications, articles, and other materials. 15

16 Additional Resources at Gas Metal Arc Welding (GMAW) Also referred to as MIG (metal inert gas) welding, GMAW creates an arc with a solid wire fed through an MIG gun and melted to form a weld. This video guides students through the basics of gas metal arc welding, which is often used in automotive, structural, and production manufacturing. Helping students identify the correct duty cycle for the job at hand, the video explains the function and specifications of the electrode, or filler wire, as well as the other GMAW tool components. Safety, transfer modes, general set-up procedures, laying and reading beads, and other topics are featured. A troubleshooting segment helps deal with problems like an erratic puddle, excessive spatter, porosity, poor penetration, and excessive penetration, with advanced GMAW techniques also explored. Correlates to all National CTE Organizational Standards (including the provisions of the Perkins Act). A viewable/printable instructor s guide is available online. A Shopware Production. A part of the series Welding Processes and Fundamentals. (23 minutes) Item: Copyright date: 2012 DVD (Chaptered) ISBN Gas Tungsten Arc Welding (GTAW) GTAW is also known as TIG, or tungsten inert gas welding, and uses a nonconsumable electrode to make high-quality welds on both ferrous and nonferrous metals. This video shows students how to properly and safely apply GTAW techniques. Pointing out tungsten s high melting temperature (the highest of any metal) and the general advantages of GTAW, the video explains AC or DC power source options as well as other system components, including the torch, foot switch, shielding gas, and ground clamp. Viewers learn how to select and prepare the right electrode (an AWS chart is featared), how to ensure safe working conditions, and how to set up the GTAW system for quality welds. An advanced segment covers joint types from butt to tee and helps troubleshoot problems like excessive tungsten wear, tungsten spitting, a porous weld, and an unstable arc. Correlates to all National CTE Organizational Standards (including the provisions of the Perkins Act). A viewable/printable instructor s guide is available online. A Shopware Production. A part of the series Welding Processes and Fundamentals. (24 minutes) Item: Copyright date: 2012 DVD (Chaptered) ISBN

17 Oxy-fuel and Plasma Cutting Preparing for a welding project usually involves cutting metal into specific shapes and pieces, a task that requires many of the same tools and know-how used in welding. This video serves as a basic guide to two popular heat-based cutting methods: oxy-fuel and plasma. Beginning with an overview of safety procedures, the video shows how to set up an oxy-acetylene system and demonstrates correct coupling distance, travel speed, torch angle, machine finishing, and other aspects of handheld cutting. Additional fuel choices are listed, too. The plasma segment includes a basic definition of what plasma is and how it can be cut. Viewers learn the fine points of setting up and cutting with a plasma system and are given numerous tips and guidelines, from one- and two-hand torch manipulation to troubleshooting various problems. Correlates to all National CTE Organizational Standards (including the provisions of the Perkins Act). A viewable/printable instructor s guide is available online. A Shopware Production. A part of the series Welding Processes and Fundamentals. (28 minutes) Item: Copyright date: 2012 DVD (Chaptered) ISBN Welding Safety This video covers the most important safety rules and protective equipment to use when performing MIG, TIG, arc, and gas welding. Welding helmets and their lens ratings, leather aprons and gloves, welding gas respirators, heat shields, and fire extinguishers are discussed, and various types of welders, including plasma cutters, are illustrated. Correlates to all National CTE Organizational Standards (including the provisions of the Perkins Act). A viewable/printable instructor s guide is available online. A Shopware Production. Part 2 of the Safety and Technology Series. (22 minutes) Item: Copyright date: 2011 DVD (Chaptered) ISBN Tools of the Trade: Inside the Welder s Toolbox This program shows viewers the safe way to work with fire, gas, and molten metal as it profiles the tools used by welders to perform a variety of tasks. Specific tools and equipment for OFW, GMAW, GTAW, and SMAW are spotlighted, along with a variety of general tools and safety items. The video also takes a look at basic welding diagrams and pre-welding treatment of materials. A viewable/ printable instructor s guide is available online. A Shopware Production. (23 minutes) Item: Copyright date: 2008 DVD (Chaptered) ISBN

18 Welding: Auto Body Repair This video puts safety first as it explains how to use an MIG (GMAW) welder. Weld types, welder setup, destructive tests, and general welding techniques are covered. The causes of contact burnback, incomplete fusion, and other problems are identified. A viewable/printable instructor s guide is available online. A Shopware Production. (23 minutes) Item: Copyright date: 2005 DVD (Chaptered) ISBN