Instructor's Guide

Instructor’s Guide

Welding Processes and Fundamentals Series Gas Metal Arc Welding (GMAW)

Introduction This guide provides information to help you get the most out of the Shopware Gas Metal Arc Welding program of the Welding Processes and Fundamentals series. As the title suggests, Gas Metal Arc Welding introduces this popular fabrication and repair process, covers the basic setup procedures involved, and illustrates basic welding techniques. This video program also describes the potential dangers that gas 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 gas metal arc welding (GMAW) systems work.

• Identify the potential dangers welding presents to trade professionals.

• Understand how a GMAW system is set up for use.

• Understand how GMAW systems are used for repair and fabrication.

43940 Gas Metal Arc Welding (GMAW) Instructor’s Guide

Program Overview This program is designed to give viewers a foundation in gas metal arc welding (GMAW) systems, their setup, and their proper use. Sections 1 and 2 of this program introduce the GMAW process and examine the physical components of a typical GMAW system. After this, a comprehensive discussion of the personal protective equipment (PPE), such as appropriate helmets, gloves, and clothing, is undertaken. Section 4 introduces the often poorly understood concept of Metal Transfer and how this occurs when GMAW equipment is being operated. The remaining sections cover the setup of a typical GMAW system and proper usage. In particular, students are shown proper GMAW 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 gas 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 Gas Metal Arc Welding This section introduces the viewer to gas metal arc welding (GMAW) and explains how the electric arc between the electrode and base metal creates molten metal that the welder uses to join the base metals together. This segment also explains the value of using an inert shielding gas to protect the molten weld puddle from atmospheric contamination.

Section 2: Components of a Gas Metal Arc Welding System Here, viewers learn about the technology and use of typical GMAW systems and practical consid- erations when using them. Students learn about the GMAW welder and DC power, details on the filler wire used, the shielding gases employed, grounding clamps and other components.

Section 3: 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.

Section 4: Types of Metal Transfer Section 4 explains that there are several distinct modes by which GMAW systems deposit metal to create welds. The two most common methods are short-circuit and globular transfer, both of which are explained in detail and illustrated via animations. Students are advised that both methods have particular applications as to where they are best used and each method has advantages and disadvan- tages that should be understood.

43940 Gas Metal Arc Welding (GMAW) Instructor’s Guide

Section 5: Setting Up GMAW for Use This section goes step-by-step through the process of setting up a GMAW system for use. Discussed is the careful examination of equipment before use, the proper settings on the GMAW welder, and the preparation of the welding tip on the electrode gun.

Section 6: Laying a Bead Section 6 goes through the process of creating high-quality welds with GMAW equipment. In the trade, this is often referred to as “laying a bead.” The many details that student welders should know when welding and laying beads are covered. Special emphasis is paid to the best two-hand techniques to use when holding the welding gun and how the proper traveling motion of the gun and arc can be used to create high-quality beads.

Section 7: Reading the Bead Good welders must be able to look at welds and beads and be able to judge their quality. When welds are created that are poor quality, welders must know the parameters that caused this, such as voltage, travel speed, gas of pressure, etc. This section covers these 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 affecting the weld 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. Topics such as root passes, fill passes, and horizontal, vertical, and overhead locations are covered.

Section 9: Conclusion This closing section shares safety tips for all trade professionals involved in GMAW along with wishes for continued success in the subject area.

Fast Facts • GMAW is the most common industrial welding process, particularly in automotive manufacturing, because of its versatility, speed, and the relative ease of adapting to robotic automation.

• GMAW was originally developed for welding aluminum and other nonferrous materials in the 1940s.

• For production environments, GMAW is quicker than stick welding techniques. This makes it well suited for softer metals like aluminum.

43940 Gas Metal Arc Welding (GMAW) Instructor’s Guide

• One of the best practices to prevent injuries is to wear personal protective equipment (PPE) whenever welding or cutting. Those who disregard this practice subject themselves to unnecessary risk.

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.

• There are four primary methods of metal transfer in GMAW, called globular, short-circuit, spray, and pulsed-spray, each of which has distinct properties and corresponding advantages and limitations.

• 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.

• 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 ra- diation 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 and cutters should not disregard the danger of these fumes.

• The presence of oily rags in the welding environment is a hazard. Sparks can travel 20–30 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.

Argon–An inactive gas commonly used as shielding. Argon is much heavier than air, so it effectively shields the weld area.

Backhand Technique–Moving the electrode along the workpiece opposite the direction of the welding bead.

43940 Gas Metal Arc Welding (GMAW) Instructor’s Guide

Bird’s Nest–The jumble of filler wire that occurs when the filler wire gets jammed in the electrode channel and the wire spool continues to turn.

Combustible–A substance that readily ignites and burns when exposed to flames and sparks.

Confined Space Permit–A special permit issued by safety organizations such as OSHA that specify 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).

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.

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.

Electrode Gun–The handpiece used in GMAW systems. Also referred to as the MIG gun, MIG torch, and GMAW torch, among other names.

FCAW–An abbreviation for flux-cored arc welding. An arc welding process that uses a continuously fed consumable electrode that contains flux in a hollowed-out center.

Filler Wire–The wire electrode that is used with GMAW and FCAW systems.

Flux–A nonmetallic material used to protect the weld puddle and solid metal from atmospheric contamination. In FCAW, flux material is contained in the core of 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.

43940 Gas Metal Arc Welding (GMAW) Instructor’s Guide

Globular Transfer–Transfer, or metal transfer, refers to the physical method whereby the filler wire from the electrode gun is melted and deposited onto the base metal. Several distinct transfer methods can occur in GMAW. Globular transfer is when the electrode wire actually melts in the arc zone and falls onto the base metal.

GMAW–Acronym for gas metal arc welding.

Inert Gas–A nonreactive gas used during cutting and welding to shield molten metals from external contaminants.

MIG Electrode–The wire electrode that is used with GMAW systems.

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.

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–Acronym 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–A GMAW technique whereby the welder “pushes” the puddle along when laying a bead, resulting in the arc being on top of the weld bead.

Purge–In welding parlance, “purging” means allowing all the gas to escape from pressured hoses.

Regulator–The valve apparatus typically installed on the top of gas tanks that is designed to meter gases for welding and cutting use.

Root Pass–A root pass is 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.

43940 Gas Metal Arc Welding (GMAW) Instructor’s Guide

Short-circuit Transfer–As mentioned before, transfer, or metal transfer, refers to the physical method whereby the filler wire from the electrode gun is melted and deposited onto the base metal. Under lower voltages the filler wire contacts the base metal and a short circuit is formed that melts the electrode. This process is repeated some 100–200 times per second and produces a sound that is described to be like “frying bacon.”

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 clean.

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.

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.

Stick-out–A term used to describe electrode extension, or the distance from the end of the contact tip to the end of the electrode.

Wire Feeder–The spool-like device either built inside the welder or set beside the welder that feeds wire to the welding gun.

43940 Gas Metal Arc Welding (GMAW) Instructor’s Guide

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 gas metal arc welding (GMAW)? How does it work? 4. Why is it so important to understand the risks and take proper precautions when using GMAW equipment? 5. GMAW generally requires a shielding gas. Why is this? 6. How can the risk of injury be eliminated? 7. Which trades are likely to need welding tasks? 8. What are the different types of welds that 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 a GMAW system works. 2. Describe the various types of personal protective equipment (PPE) that welders would use. 3. Is inspecting the welding equipment before using absolutely necessary? Why? 4. What are the basic steps to setting up a GMAW system for use? 5. How does a welder know what settings to use initially when setting up a GMAW system? 6. What are the two types of metal transfer discussed in the video? Why is knowing them important? 7. In what ways does OSHA protect welders and cutters on the job? Why are these workplace regulations important? 8. Describe the differences between using forehand and backhand methods when laying beads with GMAW. 9. What kinds of problems might a welder see with weld quality? What would one do to correct them?

43940 Gas Metal Arc Welding (GMAW) Instructor’s Guide

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—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 download- able on the school website.

• A Pictorial View of Welding Safety Practices Students review welding safety images found on the Internet and then create posters illustrat- ing 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 with the class specific experiences or situations “when things went wrong.”

43940 Gas Metal Arc Welding (GMAW) Instructor’s Guide

Assessment Questions Q1: Gas metal arc welding is often referred to as: a) Stick welding b) GMAW c) MIG welding d) Both a) and b) e) Both b) and c)

Q2: The inert gas that is released during gas metal arc welding does what? a) Cools the weld quickly b) Keeps air away from the weld puddle c) Quiets the noisy welding process d) Both a) and b)

Q5: Why is the type of metal transfer mechanism important to know? a) Because it helps you understand the welding process b) It helps you make high-quality welds c) It explains what the “frying bacon” sound is d) All of the above

43940 Gas Metal Arc Welding (GMAW) Instructor’s Guide

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

43940 Gas Metal Arc Welding (GMAW) Instructor’s Guide

Assessment Questions Answer Key Q1: Gas metal arc welding is often referred to as: a) Stick welding b) GMAW c) MIG welding d) Both a) and b) e) Both b) and c) Answer: e) When gas metal arc welding was first developed, it was called metal inert gas welding, or MIG welding. The American Welding Society broadened the term some time ago to gas metal arc welding, or GMAW. Today we use both terms, but GMAW is the preferred version.

Q2: The inert gas that is released during GMAW does what? a) Cools the weld quickly b) Keeps air away from the weld puddle c) Quiets the noisy welding process d) Both a) and b) Answer: b) Atmospheric air is composed of approximately 21 percent oxygen. Oxygen is a highly reactive ele- ment that is capable of combining with most other elements. The primary function of gas shielding is to keep atmospheric oxygen away from the molten metal. The gases used to do this are inert gases such as argon, carbon dioxide, and others.

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 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 (either auto-darkening or with a selection of 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 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.

43940 Gas Metal Arc Welding (GMAW) Instructor’s Guide

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 the many 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: Why is the type of metal transfer mechanism in GMAW important to know? a) Because it helps you understand the welding process b) It helps you make high-quality welds c) It explains what the “frying bacon” sound is d) All of the above Answer: d) There are several different metal transfer modes that GMAW equipment operates in depending on variables such as voltage, gas pressure, and filler and base metal characteristics. It is relevant to recognize what these modes are and when they are best used. The two main metal transfer modes we consider in this lesson are the short-circuit mode and globular transfer mode. Each has specific identifying characteristics (short-circuit mode sounds like frying bacon, for example) and applications when one method may be preferable to the other.

Q6: There are many settings on a GMAW system. Parameters such as voltage, current polarity wire speed, and gas volume 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 a GMAW system before use. The manufacturers of the various consumables and equipment will usually provide documentation that will assist with these settings. In addition, most manufacturers of the GMAW machines have a permanent label silkscreened on those machines that give suggested settings for various applications.

43940 Gas Metal Arc Welding (GMAW) Instructor’s Guide

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.

43940 Gas Metal Arc Welding (GMAW) Instructor’s Guide

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 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.

Additional Resources American Welding Society–www.aws.org/technical/facts 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–http://www.lincolnelectric.com/en-us/support/Pages/resources.aspx 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–www.millerwelds.com/resources/resources 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–http://nasdonline.org 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.”

43940 Gas Metal Arc Welding (GMAW) Instructor’s Guide

United States Department of Labor, Occupational Safety and Health Administration– http://www.osha.gov/SLTC/weldingcuttingbrazing/index.html 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–www.weldguru.com 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–www.weldinginfocenter.org 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.

Additional Resources at www.shopware-usa.com Shielded Metal Arc Welding (SMAW) Often referred to as “stick welding,” SMAW has been used for decades to weld most metals and al- loys. This video helps students learn the basics of the SMAW method, in which the electrode is consumable and becomes part of the weld. Identifying critical system components, the video explains different power types and power levels and includes a discussion of DCRP, DCSP, and AC modes. It then shows how to choose the correct welding rod, make sure that all equipment and working conditions meet professional safety standards, set up the system to begin work, correctly lay a bead, and read or inspect a bead. A segment on advanced techniques looks at several types of joints—edge, corner, lap, and tee joints as well as various butt joints—in addition to root, fill, and cap passes. Solving the problem of arc blow is also covered. 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)

43940 Gas Metal Arc Welding (GMAW) Instructor’s Guide

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 featured), 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)

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 ma- nipulation 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)

43940 Gas Metal Arc Welding (GMAW) Instructor’s Guide

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)

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)

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)

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