Kitabı oku: «Welding For Dummies»
Welding For Dummies®, 2nd Edition
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Introduction
Welding has become one of the most important trades in the world, and that isn’t likely to change anytime in the near future. So many of the objects people have and need are created either directly or indirectly by welding. If everyone woke up one morning and no one could remember how to join metals, the world would be a very different place by the afternoon.
But welding isn’t just important – it’s also fun. The idea of welding as a hobby is catching on more and more. It’s an extremely versatile skill that can be quite rewarding after you get the hang of it. Something is very empowering about knowing that you can harness some pretty powerful forces – electricity and intense heat – to melt metals and join them together. Even experienced welders get a kick out of the fact that they can take a machine and a few pieces of metal and create something new, functional, and even beautiful. That’s an extremely fulfilling feeling, and I think it’s a product of welding that people don’t always mention when they talk about the trade.
One quality of welding that people do talk about a lot is its usefulness. You can use welding skills to accomplish a lot, whether you want to eventually make a career out of welding or just have the ability to make and fix metal objects for your personal pursuits. Over the years I’ve taught and worked with both kinds of welders, and I know that after they really figured out the ins and outs of welding, they were able to do things that made their personal and professional lives a lot easier.
About This Book
Welding For Dummies helps you understand the basics of how welding works and lets you begin practicing several of the most prominent and useful welding techniques. I walk you through the fundamentals that hold true for all types of welding, and I dig into the details of specific welding processes – stick, mig, tig, and more – to show you how to practice those skills in a safe, productive way. Don’t worry; I don’t have you welding the Statue of Liberty’s torch back onto her hand or anything, but I do hope this book puts you well on your way to achieving the welding goals you’ve set for yourself.
One of my favorite aspects of Welding For Dummies is that you can move around within it however you want and still end up with a huge amount of welding knowledge. You may initially be interested in one welding process but quickly discover you should be reading about a totally different process, and that’s okay – you can jump to that other discussion without worrying that you’ve missed something important. Just beware of paper cuts from flipping back and forth between chapters.
Conventions Used in This Book
Here are a few conventions I use to make reading this book even easier:
❯❯ The world of welding is full of jargon, so I present new terminology in italics and make sure to give a definition nearby.
❯❯ Bold text highlights the action parts of numbered steps and also designates keywords in bulleted lists.
❯❯ I’ve tried to stick to welding standards supported by the American Welding Society (AWS), which is the largest and most prominent welding organization in the United States.
❯❯ All Web addresses appear in monofont. When this book was printed, some Web addresses may have needed to break across two lines of text. If that happened, rest assured that the address doesn’t contain any extra characters (such as hyphens) to indicate the break. So when using one of these Web addresses, just type in exactly what you see in this book, pretending as though the line break doesn’t exist.
What You’re Not to Read
Far be it from me to tell you what you should read, but allow me to make one quick point. In several spots throughout this book, I include sidebars (gray shaded boxes) that contain interesting (and possibly entertaining, depending on what kind of mood you’re in) information that you don’t absolutely have to read in order to understand and practice welding. If the how-to, functional information in the book is the entrée, the sidebars are like garnish. Not parsley, though – I like to think that the sidebars are at least a little more interesting and useful than an herb that tastes funny and doesn’t do much more than crowd a plate. You can also skip anything with a Technical Stuff icon; this information is more technically involved than the basics you need to weld.
Foolish Assumptions
I’m not really crazy about guesswork, but I did make a few assumptions about you as I wrote this book. (They’re all nice, I promise.) If any of the following statements applies to you, this book is for you.
❯❯ You’ve never welded but want to know more about metals and how to join them by using welding.
❯❯ You’ve welded a little but really want to figure out how to improve and start taking advantage of all welding has to offer.
❯❯ You’ve done a fair amount of one type of welding but want to expand your skill set so you can weld with a variety of different processes and techniques.
❯❯ You understand a few basic tools (such as hammers and screwdrivers) and what they do.
❯❯ You know how important taking necessary safety precautions is to keep yourself (and others) out of harm’s way.
How This Book Is Organized
This book is divided into six parts. Each part offers something different, but all of them are geared toward helping you figure out welding processes and put them to good use. Here’s a quick look at what you can find in each part.
Part 1: Understanding Welding Basics
This part provides the kind of welding information that crosses all types of welding. If you’re really just starting out in welding, this part is a good first stop for you because it gives you the lowdown on metals (especially the ones that are commonly used in welding), the tools and equipment you use for welding, and the kind of environment you need in order to weld successfully. It also includes the chapter that’s without a doubt the most important one in the book. That’s Chapter 3, and it’s all about welding safety.
If you read only one chapter in the book, let it be Chapter 3. Welding is a fantastic skill, but it’s not worth getting hurt over.
Part 2: Welding on a Budget: Stick and Tig Welding
Part 2 focuses on stick welding (the most commonly used welding process) and tig welding (also a great, useful technique). You can read all about the advantages and disadvantages of both stick and tig and understand how they work and what makes them unique. I explain the different equipment you need if you want to get into stick or tig welding, and I also give you plenty of information on how you can try out the techniques.
Part 3: Discovering Mig Welding
Mig welding is a fast, efficient welding process, and it’s great for new welders because it’s relatively easy to pick up and get started with. I devote Part 3 to the basics of understanding and executing mig welding.
Part 4: Getting Fancy: Plasma Cutting, Oxyfuel Cutting, and Other Processes
Arc welding isn’t the only way you can weld – welding includes lots of other processes, such as soldering, brazing, and gas welding, that are all useful in their own distinct ways. I cover those processes in Part 4.
I also cover a few cutting processes in this part, because cutting is an important task in any welding shop, and you’ll probably need to do some (or a lot) of it if you stick with welding for any extended period of time.
Part 5: Putting Welding into Action with Projects and Repairs
This part is probably the most fun because it gives you a chance to try out your welding skills and build some great, useful items. The chapters contain a welding project or two that are designed with the beginning welder in mind. You can read about how to build a portable welding table, a torch cart, a campfire grill, and more! This part also includes a chapter that helps you to figure out whether fixing something or buying (or building) it new makes more sense.
Part 6: The Part of Tens
If you’ve read a For Dummies book before, you already know all about this part. The Part of Tens is always a favorite; it features lists full of useful information in an extremely easy-to-read format. You can read about the advantages to becoming a certified welder, the tools that every welder wants, and more. There’s also a glossary to help you with basic welding terminology.
Icons Used in This Book
Throughout the book, you’ll occasionally notice little pictures in the margins. These icons help flag specific information I want to highlight; check out the following list for details on what those icons indicate.
When you see this icon, expect to find a helpful bit of information that will help save you time and money and keep you from making mistakes when you’re welding.
If I really want you to slow down and commit something to memory, I use this icon. It’s important stuff, so take the time to read it!
The last thing I want is for you to get hurt, or for you to hurt others or damage property. With that in mind, please pay attention to these icons so you can keep from hurting someone (yourself included) or damaging your equipment or surroundings.
This icon denotes technical or historical information that’s more involved than what you need for your basic welding practice.
Where to Go from Here
I know what you’re thinking: With all of this terrific, useful welding information, where do I begin?
I certainly don’t want to tell you what aspect of welding you should want to read about first – that’s for you to decide – but I do make one request. If you’re new to welding, or if you aren’t completely familiar with the practices of welding safety, please go directly to Chapter 3 and read up on it. You really do need to know how to keep yourself safe as you start or continue your welding experience, and Chapter 3 goes a long way toward keeping you out of harm’s way.
After you’re done reading Chapter 3, please feel free to jump around in the book however you see fit. There’s a whole world of welding out there, and Welding For Dummies is a great way for you to start exploring it.
Part 1
Understanding Welding Basics
IN THIS PART …
Get familiar with metals – specifically, those you’re likely to work with as a beginning welder.
Find out how to set up your welding shop (which may be trickier than you think).
Learn about important safety precautions you must take before trying any sort of welding operation.
Chapter 1
Diving Into the World of Welding
IN THIS CHAPTER
❯❯ Discovering the main uses for welding
❯❯ Examining common welding metals
❯❯ Paying special attention to welding safety
❯❯ Taking a look at welding methods
❯❯ Thinking about what’s in store for welding in the future
Ever since our early ancestors starting making ornaments out of gold thousands of years ago, metal has played an important role in the lives of all people. Just take a second to look around and think about all the various kinds of metal that are nearby. Dozens (if not hundreds) of metal items are probably all around you, and the items that aren’t made out of metal were likely manufactured by using metal equipment.
By and large, metal is tough stuff. (That’s one of the reasons why it’s so useful, of course.) Throughout history, humans have needed to come up with more and better ways to defy the strength of metals, bending, cutting, and joining it so they can take advantage of its many useful properties. One of the biggest and most important advancements on that front has been the advent and development of welding. Welding allows humans to connect pieces of metal in remarkably strong, sturdy ways, and it has opened up seemingly endless possibilities for what people can do with metallic materials.
This chapter introduces you to all things welding, including its importance, the materials, equipment, and methods you use to accomplish it, and the need for safety precautions while doing it. In addition, the chapter gives you a glimpse into welding’s crystal ball.
If You Can’t Beat ’Em, Join ’Em: Understanding Why Welding Matters
Welding is the process of using heat to join metals. When you’re looking to join metals, you can find no easier or more cost effective way to get the job done than welding – it allows you to join metals in a way that’s faster, more versatile, and more dependable than any other process (by a long shot). (And no, using duct tape doesn’t count because that’s not really fixing anything.) The availability and cost of so many of the items you depend on every day are kept within your reach because of the widespread use of welding processes. Just how prominent is welding? Well, it’s estimated that half of the U.S. gross national product is affected by welding. That’s about $7 or 8 trillion. How many other skills or trades can claim that much of an impact? Not many.
The uses of welding break down into two very broad categories: fabricating and repairing. The following sections offer a little more detail on both of those divisions.
Fabricating metal products
In welding, fabricating simply means that you’re taking pieces of metal and welding them together to create something new. That can be as simple as welding a few pieces of metal together at a 90-degree angle to make a pair of bookends in the welding shop you set up in your backyard, or as complex as using underwater arc welding to help build a section of submerged pipeline off the coast of Angola. (Don’t worry – you can expect a lot more of the former than the latter in this book!)
Most metals can be joined by one welding process or another, so in theory you don’t have many limits when it comes to fabricating. However, for a new welder the amount of fabricating you do with your newfound welding skills is often limited to some degree by cost (some metals can be pretty expensive), time (if you’re welding as a hobby, chances are your fabricating time takes a backseat to other obligations like your job and your family), and degree of difficulty. Because developing your welding skills takes time, some fabrication projects may be out of your reach in the short term.
Repairing metal pieces or products
The difference between fabricating and repairing is simple. When you weld to fabricate, you’re making something new. When you weld to repair, you’re welding on something that already exists but needs fixing or modifying. Repairing can be as simple as welding to fix a tine on your favorite old rake, or welding to fix a crack in a helicopter fitting assembly. (Of course, I lean a lot more toward rake repair than helicopter maintenance in this book!) Although metals are durable and tough, they do break down because of damage or repetitive use, and when that happens, welding is the best way to fix them.
TRACING THE HISTORY OF WELDING
Welding is one of the newest metal-working trades; it can be traced back to about 1000 B.C. Most historians agree that the first kind of welding done by humans was the lap welding of gold, which was used to create simple gold ornaments. But welding really started to take shape when people figured out how to hammer brass and copper together to make bronze. Bronze was a real game changer, especially when it came to making basic types of farming equipment and tools, or weapons of war.
The next big jump in technology was during the Industrial Revolution (from the mid-1700s to the mid-1800s). That’s when hammer welding (also known as forge welding) was developed. In hammer welding, metal is heated to its plastic state, and then two separate pieces are laid side by side and hammered together. (If you’ve ever seen a blacksmith at work, you’ve seen hammer welding in action.)
The next step was based on the discovery of acetylene in the middle of the 19th century. Controlled use of acetylene gas (combined with oxygen) allowed people to cut and melt metals in a way that wasn’t possible before. But welding as you know it today came about in the early 20th century, after people had learned how to harness and use electricity. Very basic electric welding equipment and techniques were already being used across the globe at that point, and World War I made it clear that welding technology was going to be critically important for cranking out massive amounts of metal materials, tools, and machinery. Many of the prominent organizations and companies that loom large in the world of welding today got their start during that period. Improvements in welding processes and equipment came in leaps and bounds, and before the first half of the 20th century was over, the world had seen the creation of the major welding techniques that I cover in this book: stick welding, mig welding, tig welding, and oxyacetylene welding, as well as oxyfuel welding and cutting.
The big question with repair work is whether it makes more sense (especially with regard to time and money) to make a repair or simply replace the broken part or product. That’s not always an easy call to make, and I address the various facets of that question in Chapter 18.
When you’re welding to repair something, your goal should always be to produce a weld that’s stronger than the original piece or product. If you’re going to be working on something, why not improve it?
Getting Familiar with Metals
Any welding endeavor is much easier if you have a solid working knowledge of metals. The more you know about the metals you’re using and how they’re likely to respond to the intense heat involved in welding, the more likely you’ll be able to manipulate and join them in the way you have in mind for a specific project.
You probably remember from your high-school science class that, like other materials, metals expand when you heat them and contract as they cool off. If you heat them enough, they start to get soft, and eventually (with more heat), they melt. I know that sounds simple, but it’s awfully important for welding. Some metals melt at relatively low temperatures, and others have extremely high melting temperatures. A metal’s melting point is just one of several important properties for welding.
Here are just a few others to consider:
❯❯ Ductility is a metal’s ability to change shape (bend, stretch, and so on) without breaking. Gold has a high level of ductility, whereas tungsten isn’t very ductile at all.
❯❯ Electrical conductivity is a measure of how well a metal can conduct a current of electricity. Copper conducts electricity really well; by comparison, stainless steel isn’t a great conductor of electricity.
❯❯ Strength is pretty self-explanatory: How much external force can a metal withstand without breaking? This one is very important for welding. Steel is a strong metal, but zinc isn’t.
You can read up on many more properties of metal, and the more you know, the more easily you can make smart decisions about how to weld those metals effectively.
Not all metals are widely used for welding, of course, and you probably won’t work with a huge range of metals in your welding shop until you’ve been welding for a while. That’s completely fine, however, because plenty of exciting welding projects – both fabricating and repairing – involve only a few select metals. (See “If You Can’t Beat ’Em, Join ’Em: Understanding Why Welding Matters” earlier in the chapter for more on those divisions.) For example, most of the welding practice exercises I walk you through in this book, as well as the welding projects I detail in Part 5, focus on three metals: steel, stainless steel, and aluminum. These three are the most commonly used metals for beginning welders, and you should take the time to get to know them. In the following sections, I give you a quick look at each one.
Steel
Steel is a strong, versatile metal that you’ll use all the time in your welding projects. You may not realize it, but steel is really an alloy made up of iron and less than 2 percent of another material. Carbon is often used in steel alloys, and you can find three different levels of carbon steel: low-, medium-, and high-carbon steel. The more carbon in the steel, the stronger the alloy is.
You should use steel in your welding projects when you’re looking for a strong metal that’s pretty easy to weld and doesn’t break the bank when you’re buying your materials. You can use any welding process I describe in this book on steel, so versatility is also one of its strong suits. But steel also has its downsides. For one, it’s heavy. If you want your fabricated project to be light, steel probably isn’t your best bet. Steel is also prone to rusting and scaling (flaking off due to oxidation), so you have to spend a fair amount of time cleaning it up (often with a grinder) before and sometimes during welding.
Stainless steel
Stainless steel is amazing stuff. It has a lot of the good qualities that regular steel has (see the preceding section), but it also offers one added bonus: It resists corrosion (rust, for example) like a champ. You can put a piece of stainless steel out in the yard and let it get rained on for six weeks, and when you bring it back inside it probably won’t have a single spot of rust on it. Incredible!
How does stainless steel provide such remarkable resistance to corrosion? Its alloy contains 10 to 30 percent chromium (the rest is iron, although sometimes other metals, such as nickel, are also added to the alloy).
You can weld stainless steel with all three of the major types of arc welding (stick, mig, and tig). It’s a great choice if you want your project to resist rusting or to have hygienic surfaces (those that don’t harbor bacteria and other microscopic critters).
Stainless steel is pretty expensive compared to other commonly welded metals, so be prepared to open your wallet a little wider if you choose stainless steel for a welding project.
Aluminum
Like stainless steel, aluminum is great at resisting corrosion. And aluminum offers another pretty terrific characteristic: It’s lightweight. Compared to steel and stainless steel, aluminum is a real featherweight.
Pure aluminum is a popular choice for welders, but aluminum alloys are also frequently used. Copper, manganese, and zinc are just a few of the metals that are often alloyed with aluminum to produce enhanced characteristics in the finished product.
If you’re going to be welding aluminum, I recommend going with tig welding. It just makes for a cleaner, easier job. If tig isn’t an option, take mig welding; you can stick weld aluminum, but it’s not ideal – your choices for stick electrodes are going to be limited, and you’re probably going to have a difficult time maintaining the correct arc length.
Taking the Time to Understand Welding Safety
Welding utilizes some pretty extreme forces and materials. Most modern welding requires tremendous amounts of electricity, which of course can create a risk for electric shock. No matter what kind of welding you pursue, you’re always going to be working around some incredible levels of heat, too, and those kinds of temperatures can harm you, other people, and your property in myriad ways. The metals you weld are sometimes sharp and often heavy, so with them you can get that rare and unfortunate double threat for lacerations and back injuries. Finally, you can’t forget other potential hazards that welding can create, including rays that can do serious damage to your eyes and fumes that can hurt your lungs and make you very sick.
Welding is a safe endeavor if you follow all the necessary precautions and respect the equipment, materials, and process. I know as well as anyone that welding involves a lot of potentially hazardous elements, but I also know that if you make maintaining a safe welding environment your first priority, you can weld for years and years without suffering any serious injuries or loss of property. You just have to follow the safety rules and keep your head on straight.
As you work your way through this book I ask only one favor of you: Please read Chapter 3 (on welding safety) carefully and thoroughly. Even if you think you understand welding safety, taking a few minutes to review the key steps for creating a safe welding environment for yourself and others can’t hurt.
Exploring Welding Methods
You can use heat to join metals in several different ways, but by far the most common welding methods used today are the arc welding methods. Arc welding is really pretty simple in theory: A large amount of electricity creates an arc between an electrode and a base metal, and that arc generates enough heat to melt the materials in the weld area and join them together to make a weld. In practice, however, arc welding includes three different welding processes (stick, mig, and tig) and has many different variables. For example, some kinds of arc welding use a shielding gas, whereas others don’t. The electrodes that you use in arc welding may be consumable, meaning they get melted and incorporated into the weld, or they may be non-consumable. The electricity used in arc welding is the source of many other variables, including amperage (which can vary a lot) and current (either alternating current or one of a couple different forms of direct current).
Because the three main types of arc welding are the most commonly used throughout the world and the easiest to pick up, those are the three that I devote the most attention to in the following sections (and throughout the book). However, they aren’t the only game in town, so I also include some information on those other types in case you want to branch out a bit.
Stick welding
Stick welding (also called shielded metal arc welding or SMAW) is an arc welding technique that has the distinction of being the most commonly used welding practice in the United States today. (More than 40 percent of all welding done now in the United States is stick welding.) The prevalence of stick is even stronger in construction; more than half of all construction-related welding uses stick. And the percentage is even higher in the maintenance industry.
Stick welding enjoys such popularity for three primary reasons. First off, it’s cheap. You can get into stick welding for less money than you’d spend to get started with tig welding. Secondly, stick welding is highly portable. The equipment is lightweight, and you can easily use it outdoors if the conditions allow it. Finally, stick welding is versatile. You can use it to work on metals with a wide range of thicknesses, and you can stick weld in just about any position that fits with your skill level.
Stick welding is great, but it isn’t perfect. One main reason is that it’s messy. Welding waste products, such as slag and spatter, get thrown around during a stick weld a lot more than they do when you’re tig or mig welding. Because of that, you have to plan on spending some time cleaning up your welds and weld area after you’re done stick welding. Another of stick’s imperfections is its speed (or lack thereof). You have to be pretty good at stick welding to do it quickly (especially compared to, say, mig welding).
You can read all about the stick welding process in Chapters 5 and 6, but generally speaking, stick welding utilizes a consumable electrode with a solid metal rod in its core that melts down and forms part of the weld. Small globules of molten metal flow from the tip of the electrode through the electric arc to the molten weld pool. The electrodes have a coating of flux that protects the molten metal from impurities in the air that can contaminate the weld as it cools.
Mig welding
Mig welding is another arc welding technique. You may also hear mig welding referred to as gas metal arc welding (GMAW) or wire welding. Mig welding is becoming more and more popular, for several reasons. At the top of the list is the fact that most people find mig welding to be easier to pick up than stick and tig. Another big reason is the speed; done correctly, mig welding can be quite a bit faster than stick or tig welding thanks to its continuously fed wire electrode, which doesn’t require changing nearly as often as the stick electrodes used in stick welding. You can just keep right on welding without having to stop and change your electrode. Over the course of a welding project, that can definitely save you quite a lot of time.
Proponents of mig welding also cite the low amount of slag and spatter that mig produces. That makes for a more pleasant welding experience, and a much more pleasant cleanup experience. The low chance of distortion (unwanted changes in a piece of metal’s shape) is also trumpeted by those who love mig welding. Because the process is faster, you don’t need to apply as much heat to the weld area for as long, so the metal is less likely to bend and twist in nasty ways.
Of course, mig welding also has its downsides. For starters, mig welding equipment is more complex than stick welding equipment, so it’s quite a bit more expensive. The handheld part of the mig welding equipment (called the mig gun) is often big and bulky, so it’s usually tough to mig weld in tight spaces. Mig welding also relies on the use of a shielding gas to keep atmospheric contaminants away from the weld area, so the process doesn’t really work very well outdoors (especially with any kind of breeze).
I save the details of the mig welding process for Chapters 9 and 10, but generally speaking, here’s how it works: A wire feeder continuously feeds the wire electrode to the weld area at a speed you control. That produces a steady molten stream that you can easily direct however you want on the surface of the metal you’re welding. The weld is completely covered with a shielding gas (usually argon) to prevent impurities from fouling up the quality of the weld; you control the flow of the shielding gas to suit your project’s needs.
Tig welding
The last type of arc welding is tig welding, which is sometimes called gas tungsten arc welding or GTAW. One major advantage to tig welding is that it’s extremely clean. If you’re tig welding correctly, you may very well go through an entire project without having to spend any substantial amount of time cleaning up. Tig is also extremely versatile. You can use tig welding to work on a lot of exotic metals that just aren’t in play for, say, stick welding.
Tig welding has two big drawbacks. One is cost – you can definitely spend a pretty penny on tig welding equipment and supplies, even for start-up. The second drawback is lack of speed. You get a lot of precision out of tig welding, but you pay for it with time.
The tig welding process was originally developed in the 1940s to join aluminum and magnesium, but you can use tig welding to join all kinds of different metals. The big difference in tig welding is that it uses a non-consumable electrode that’s almost always made of tungsten. It also requires the use of a water- or air-cooled torch, which holds the tungsten electrode and is connected to the welding machine by a power cable. Like stick welding (see the earlier section), tig uses an arc of electricity to heat metal to its melting point, and you manipulate the puddle to join metals together. The major difference is that tig welding uses a tungsten electrode. You can read more about tig welding in Chapters 7 and 8.
Other welding methods
There’s more than one way to skin a cat, and there are more welding processes beyond the big three arc welding techniques (see the preceding sections). Here are a few to consider; check out Chapter 13 for more info.
❯❯ Brazing is unique among the welding processes because you can use it to join different materials (two different metals, for example). It uses gas rather than electricity, and the heat used in brazing surpasses 800 degrees Fahrenheit.
❯❯ Soldering is a form of welding that uses (relatively) low amounts of heat. You can solder at temperatures below 800 degrees Fahrenheit. (That’s downright chilly when it comes to welding.) You can solder with gas or electricity, but the electricity you use in soldering isn’t the same as the type of electricity you use in arc welding. Instead, soldering uses an electric soldering iron that heats up and melts the filler materials you’re adding to the project you’re working on.
❯❯ Oxyfuel/oxyacetylene welding is probably the most common gas welding process. You do it with a gas-powered flame that melts the base metal and any filler materials necessary to make the weld. The equipment used for this type of welding is the most portable and low cost in the welding world.
Looking at the Future of Welding
The need for skilled welders is huge right now, and it’s only going to continue to grow. New metal alloys are being created and used for a wide range of purposes every day. The industries that rely on welding are expanding rapidly across the globe, and the need for metals to be joined in skillful ways isn’t going anywhere in the near future. Welding is a versatile field that you can study in a number of different ways, from on-the-job training to education at a vocational or technical school. If you practice and develop your welding skills and work hard, you can more than likely make a career out of welding. And after you’ve been a welder for a while, you can very easily transition into a position as a welding supervisor, on-site supervisor, or inspector, just to name a handful of the possibilities.
But don’t think that you need to make a career out of welding in order to enjoy and appreciate the process. You can weld to fix things around your house, yard, or farm. You can weld to create things that you use in your personal or professional life. You can weld to create works of art or gifts for friends and family. Or you can weld just because it’s fun and rewarding (and there are few better reasons to weld than that).
Chapter 2
Considering Commonly Welded Metals
IN THIS CHAPTER
❯❯ Understanding steel
❯❯ Getting a grip on stainless steel
❯❯ Taking a look at aluminum
❯❯ Reflecting on a few other metals
Good chefs know food, good carpenters know wood, and any good welder really knows metal. I know that sounds painfully obvious, but I’m sometimes surprised to learn that many seasoned welders aren’t all that familiar with the metals they work with on a daily basis. I think having a nice, rounded understanding of the metals you weld is important, and that’s what this chapter is all about.
If I had to pick three metals that most new welders want to begin working on as soon as possible, I’d have to go with steel, stainless steel, and aluminum. If you can familiarize yourself with those three metals and understand their characteristics as they pertain to the various types of welding, you’re well on your way to figuring out how to work with three of the most common, versatile metals out there. With that in mind, I start this chapter by devoting individual sections to each of those three metals. After that, I close the chapter with a quick look at some of the other metals that you may want to consider welding, just to clue you in on some basics and give you a feel for what’s possible beyond the old standbys.
Steeling Yourself for Using Steel
Steel is an extremely common metal. It’s all around you – chances are, you’re probably not more than a few feet away from something made of steel. For that reason alone, it’s a very important metal for welding.
Steel is an alloy that’s made up primarily of iron, along with less than 2 percent of another material. That material is usually carbon, and the amount of carbon present in the steel is an important feature. Here’s a quick look at the three different levels of carbon steel:
❯❯ Low carbon or mild steel has less than .2 percent carbon. This category of steel is extremely easy to work with; you can cut and form low carbon or mild steel a lot easier than many other metals. Lots of objects, including screws, bolts, nuts, and washers, for starters, are made of low carbon steel. Sheets of low carbon or mild steel are often used to make automobile bodies and other familiar products.
❯❯ Medium carbon steel has .25 percent to .55 percent carbon, and it’s more difficult to work with and form than low carbon steel. You can find medium carbon steel in some of the same products made of low carbon steel, but the medium carbon versions are stronger. Machine parts (gears, axles, levers, and so on) are also often made out of medium carbon steel because of its strength and durability.
❯❯ High carbon steel is the really tough stuff. More precisely, it contains between .55 percent and 2 percent carbon. It’s the hardest and strongest type of steel, but it can be a real pain to cut and form. Manufacturers use high carbon steel to make things like cutting tools, files, and hammers because those items need to be strong enough to keep their shapes and integrity through years of heavy abuse.
Getting a handle on forms of steel
Steel is manufactured in many different forms, and each form has its own use for welding projects. Here are a few of the more common forms that you’re likely to run into as you weld:
❯❯ Flat steel is exactly what it sounds like – a flat piece of steel. It’s also called sheet steel. It comes in a range of thicknesses and sizes, but when it’s larger than 12 inches wide, it’s called plate steel.
❯❯ Steel bars are made in an array of shapes, but the most common are round, square, or flat. You can see some examples of steel bar shapes in Figure 2-1.
FIGURE 2-1: Square (a), flat (b), and round (c) steel bar shapes.
❯❯ Rolled steel comes in two forms.
● Hot rolled steel is made to its finished size while the steel is still red hot. Iron oxide forms on the hot steel after it’s rolled. It’s a grayish-black coating that helps protect the steel from rusting. Hot rolled steel is used for piping, tubing, tanks, and other products.
● Cold rolled steel is made by rolling the steel to its finished size after it’s cooled to room temperature. It doesn’t get the iron oxide that hot rolled steel gets, so cold rolled steel is smooth and bright looking. It’s used for making things like nails and screws.
Like all other metals, steel goes through some changes when you apply the high levels of heat to it that are necessary for welding. The steel around the weld area is subject to distortion and cracking due to the expansion and contraction caused by all that heating and cooling. The good news is that the electrodes and filler metals you use when welding steel are designed to be just as strong (or even stronger) than the metal you’re welding, as long as you let the weld cool off on its own after you’re done welding.
Knowing when steel is appropriate
Steel is such a ubiquitous metal that it’s hard to imagine life without it. It has become an important part of everyone’s life, and the ways you live, play, and travel certainly wouldn’t be the same if steel was no longer available.
You can use steel for a wide variety of welding projects; it’s cheap, readily available, and pretty easy to weld. If you’re looking to weld objects such as farm equipment, tools, cars, automotive equipment, specialty containers (drums, pipes, and boilers), or even bridges and parts of buildings, you should strongly consider steel as your metal of choice.
When is steel not appropriate for welding? Well, if you’re working on or repairing a piece of metal that’s definitely not made of steel, such as repairing an aluminum piece on a boat, using steel won’t work for that project.
If you’re starting a new welding project from scratch and really need to end up with a lightweight product, steer away from steel. Steel is durable and cheap, but it’s also pretty heavy compared to many other metals. Steel also doesn’t work if you’re welding something to be used for any sort of food service application; food almost always involves water of some sort, and water rusts steel, creating an unsanitary environment. For the same reasons, using steel for anything in a medical setting is also a bad idea.
THE MANY PROPERTIES OF METALS
It’s a little hard to believe how many different kinds of metals are out there. Metals run the gamut from tungsten, which is one of the hardest materials on Earth, to mercury, which is a liquid at room temperature. Here are a few of the physical properties of metals that combine in different ways to make metals unique.
● Strength: How much external force the metal can take without breaking.
● Ductility: The ability to change shape without breaking.
● Magnetism: Some metals (like steel) are magnetic; others (like aluminum) aren’t.
● Hardness: The resistance of a metal to being damaged when another metal is applied to it.
● Resistance to oxidization: When metals combine with oxygen, they become oxidized. That’s what causes steel to rust, for example. Some metals – tungsten, for instance – are very resistant to oxidization.
● Electrical conductivity: Some metals conduct electricity much more efficiently than others. For example, silver is an incredible conductor of electricity, but stainless steel doesn’t conduct well at all.
● Melting point: Every metal has a melting point – the temperature at which the metal turns from a solid to a liquid. This property is critical in welding because, of course, you’re trying to melt metal. Tungsten has the highest melting point; you need temperatures of 6,170 degrees Fahrenheit to melt tungsten. That’s remarkably high compared to, say, tin, with a melting point of only 450 degrees Fahrenheit.
For more great information on steel, check out the American Iron and Steel Institute’s website at www.steel.org.
Preparing steel for welding
All metals have to be cleaned and prepared before you weld them, and steel is definitely no exception. Quality welds aren’t going to happen if your steel is covered with surface contaminants. And some of those contaminants can be downright dangerous to your health if they’re heated up and converted to fumes while you’re welding. (Flip to Chapter 3 to read all about the safety gear you can get to protect yourself from fumes.)
You especially need to do your best to remove rust from the surface of your steel. Rust is especially common on mild steel (covered earlier in this chapter), and it can wreak havoc when you’re trying to produce a high quality weld. The most common defect you experience as a result of rust is porosity (the presence of lots of little holes) in your welds, and porosity can really ruin a good weld joint.
If you want to use a steel that’s less prone to rusting, try one that has a little chromium added to it. Chromium slows down corrosion processes in steel. You can also try weathered steel, which has a copper alloy in it and holds up well outdoors.
You can use one of two methods for cleaning your steel prior to welding: chemical or mechanical. The method you choose depends on the metal type, the condition of the metal, the welding process you’re planning to use, and the equipment available.
Don’t assume that a piece of steel (or any metal for that matter) is clean just because it looks clean. Even a new piece of steel fresh from your welding supply store has contaminants on the surface that you need to clean off prior to welding.
Cleaning steel with mechanical methods
When you clean your steel mechanically, you clean the surface by scraping, brushing, or grinding. I usually clean pieces of steel by hand (without power tools) only when the pieces are very small because power tools are just faster otherwise. If you opt to clean steel by hand, I recommend using a very sturdy wire brush. (Check out Chapter 4 for information on wire brushes and other basic tools you need for welding.)
When cleaning a metal before welding, make sure that the metal in your wire brush or the metal on the attachment you plan to use on your power tool is the same as the metal you’re going to weld. For example, if you’re going to be cleaning a piece of steel, make sure you use a steel wire brush or grinder, not one made of brass or another metal. Otherwise, you run the risk of contaminating the metal with another metal. The exception? It’s okay to use a stainless steel wire brush on aluminum.
Tools powered by electricity or pressurized air have become the standard for cleaning steel in many welding shops, especially for shops that weld large pieces. The most common power tools used for cleaning steel are angle grinders, shown in Figure 2-2. An angle grinder in use is depicted in Figure 2-3.
FIGURE 2-2: A typical angle grinder.
You may think that you can ease up a little on your safety precautions when you’re cleaning a piece of metal but not yet welding it, but don’t be fooled. You can be injured during the cleaning process, particularly if you’re using power tools to clean the metal. Head to Chapter 3 for the lowdown on safety.
Cleaning steel with chemicals
Chemical cleaning is, as you can probably guess, a way to clean steel by using harsh chemicals. I’m talking about some pretty rough chemicals here, so if you go the chemical cleaning route, please be sure to treat the materials with the utmost respect.
FIGURE 2-3: Cleaning steel with an angle grinder.
The chemicals used to clean steel before welding are caustic and extremely dangerous. They can do serious damage to your eyes and skin. Before using any of these chemicals, be sure you’ve read and understand the Material Safety Data Sheets (MSDS) that lay out their risks. Pay special attention to the ways in which you combine these chemicals because many of them react violently if you mix them up.
You can clean steel with several different chemicals, and here are a few that you may want to consider.
Almost all the solvents used to clean steel and other metals before welding are extremely flammable, so be sure that no spark or flame ever comes in contact with the solvent or its fumes. If you clean steel with one of these solvents, make sure the metal is completely dry and the solvent has evaporated or dissipated before you begin welding. Also, be sure to keep your solvent containers in a safe place away from your welding area, as I note in Chapter 3.
❯❯ Acetone: This harsh chemical removes rust and oxidation from steel. Welders usually use acetone by spraying it on and rubbing or wiping it off with a clean rag. Compared to some of the other solvents sometimes used to clean metal, acetone is relatively mild, but it’s still a toxic material, so proceed with caution.
❯❯ Alcohol: You can use alcohol for light cleaning and for degreasing. I recommend spraying it on and wiping it off with a clean rag or cloth.
❯❯ Acid: You can use sulfuric or hydrochloric acids to remove rust scales and oxidation from steel before welding it. These substances are dangerous, so use extreme caution if you go this route – in fact, I recommend cleaning with acid only as a last resort. After applying the acid, make sure you rinse the area thoroughly with hot water and dry it as soon as possible.
Exploring steel welding methods
You can weld steel with just about any of the welding methods I describe in this book, but I recommend sticking with the big three arc welding techniques – stick, mig, and tig. Here’s a quick look at a few steel welding specifics to keep in mind for each of those processes.
Stick welding
Stick welding works just fine for joining steel. It’s extremely portable – which comes in handy when you need to weld a huge piece of steel that you can’t easily move – and as you can read in Chapters 5 and 6, stick welding is versatile and inexpensive compared to the other welding methods. You can use stick welding on virtually any piece of steel that’s 1/8 inch thick or thicker.
Mig welding
You can mig weld steel in any position, and that’s one of the reasons mig is the most popular choice for steel welding projects. Another reason: You can get a very smooth steel weld with mig, and you can also avoid a lot of the spatter and waste that you may get with stick welding. You’ll have a hard time finding a piece of steel you can’t weld with mig; very thick pieces of steel work out fine as long you have a powerful mig machine, and you can even weld extremely thin pieces of steel with mig welding.
Tig welding
Like mig welding, tig allows you to join all different thicknesses of steel. Tig also affords the advantage of a very clear view of your welding area, because tig produces very little smoke or slag (waste).
If you choose tig for your steel welding jobs, make sure you have your equipment set up correctly. Ask your welding supply shop for the charts that help you determine the correct amperage, shielding gas flow rate, and polarity for tig welding steel. You also need to be sure that you use the right filler rod (a metal rod that melts and becomes part of your welding puddle to add strength to your weld), or the quality of your weld may suffer greatly.
Don’t use oxyacetylene filler rods when you’re tig welding. The copper coating creates impurities in the finished weld.
Going with Stainless Steel
Stainless steel is pretty incredible stuff. It’s remarkably durable and strong, and as a result it’s used in countless applications all over the world. I doubt you’ll be able to practice welding for long before some stainless steel object catches your eye as a possible project component (if it hasn’t already).
Understanding the differences between steel and stainless steel
Stainless steel is different from regular steel because it contains 10 to 30 percent chromium. Chromium is added to the steel to create the resistance to corrosion that makes stainless steel so famous (and useful!). Stainless steel can contain a few other substances that make it perform at an even higher level; nickel is the most common.
Stainless steel today is classified into two general series:
❯❯ The 200 to 300 series includes stainless steels made with chromium, nickel, and sometimes manganese. They’re more resistant to corrosion than the 400 series, and they generally have better qualities for welding.
❯❯ The 400 series includes stainless steels that don’t contain nickel. They can’t be hardened as much as the 200 to 300 series.
Stainless steel’s most notable (and desirable) quality is its resistance to corrosion. The combination of steel and chromium creates an outer surface that’s terrific at resisting rust. Because of that quality alone, stainless steel is used in a huge variety of applications, from beer kegs to hypodermic needles to the St. Louis Gateway Arch.
Deciding when to use stainless steel
Why would you want to use stainless steel in one of your welding projects? Here are a few examples.
❯❯ You need part or all of the project to be rust-proof. This goal is pretty self-explanatory, but if your project is going to be located outside – especially in an area that gets a lot of precipitation or salt abuse – and you can’t let it get rusty, stainless steel is one option to consider.
❯❯ You don’t mind spending some extra money. Compared to other metals (carbon steel, for example), stainless steel is expensive! It can cost as much as five times more than steel.
❯❯ You need part or all of the project to be hygienic. The strong, consistent surface of stainless steel means that it doesn’t have tiny irregularities in the surface that bacteria and other critters can cling to. It also means that you can clean the surface with some pretty powerful cleaners without damaging the material. For those reasons, stainless steel is a popular choice for food preparation and storage equipment, and also for medical purposes.
Looking at stainless steel welding methods
If you want to weld stainless steel, your three best options (by a mile) are stick welding, tig welding, and mig welding. Generally speaking, stainless steels are slightly more difficult to weld than carbon steels. That’s because stainless steels have lower melting temperatures, and more thermal expansion (they expand more than steel when heat is applied).
❯❯ To stick weld stainless steel, you have to use a flux-coated electrode, which protects the metal from the air while you’re welding and helps make the weld even more corrosion resistant. Keep in mind that stick welding is the messiest of the arc welding methods, and that can be a drawback when you’re welding stainless steel. The random arc marks and spatter caused by stick welding can compromise stainless steel’s pristine surface and appearance.
When selecting stick welding electrodes for stainless steel welding projects, make sure you pick electrodes that have a -15 or -16 suffix. For example, a commonly used electrode for stick welding stainless steel is E-308-16. For more information on picking out stick welding electrodes, take a look at Chapters 5 and 6.
❯❯ Tig welding stainless steel is a great option when you’re looking to weld thin pieces. I recommend using argon as your shielding gas. You can read more about shielding gases for tig welding in Chapters 7 and 8.
❯❯ Mig welding is nice and fast, so it’s the ticket if you want to weld thicker pieces of stainless steel. In those cases, tig welding can just take too long.
Working with Aluminum
If you’re looking for a strong, lightweight metal, chances are your search can stop at aluminum. It’s a remarkably versatile material that’s usually at or near the top of the list of most-welded metals. If you stick with welding for very long, you’re probably going to want to weld some aluminum, and I can’t blame you. Read on to find out more about welding this wonderfully dynamic metal.
Perusing the properties of aluminum
So what makes aluminum so special? For starters, it reacts with oxygen in the air and produces a very tough oxide film on the surface. This aluminum oxide is extremely durable, and it effectively protects the metal underneath it. (That’s why aluminum is so resistant to corrosion.)
The aluminum oxide film that covers pieces of aluminum that have been exposed to the air for long periods of time has a higher melting point (3,600 degrees Fahrenheit) than the pure aluminum underneath it (1,200 degrees Fahrenheit). For this reason, you have to remove the film before you can weld aluminum.
Aluminum conducts heat about five times better than steel, and interestingly, it doesn’t change color when you heat it up. (Steel, of course, turns all kinds of different colors as you heat it up to different temperatures.) It weighs about one-third as much as steel.
Pure aluminum is a popular choice for welders, but many different aluminum alloys have also been developed. A classification system of four-digit numbers has been created to identify the various aluminum alloys. The first digit is the really critical one because it tells you what is included (other than aluminum, of course) in the alloy. Here are the details:
❯❯ 1XXX: Unalloyed aluminums made up of at least 99 percent pure aluminum
❯❯ 2XXX: Copper
❯❯ 3XXX: Manganese
❯❯ 4XXX: Silicon
❯❯ 5XXX: Magnesium
❯❯ 6XXX: Silicon and magnesium
❯❯ 7XXX: Zinc
❯❯ 8XXX: Other materials (tin is one example)
The two types of aluminum you’ll probably weld most often are pure aluminum and aluminum alloy 3003.
Recycle your old aluminum! Almost two-thirds of the aluminum used today has been recycled, and that’s the environmentally responsible thing to do.
Eyeing aluminum welding techniques
If you ask me, welding aluminum isn’t any more difficult or problematic than welding steel. It can take some getting used to, but after you have the hang of it, you can weld aluminum quickly and efficiently by using any one of the three major arc welding methods: stick, tig, and mig.
❯❯ My first choice for welding aluminum is always tig welding. You need to use alternating current (AC) with continuous high frequency to get the best results. (If those terms don’t make any sense, flip over to Chapters 7 and 8 for more information on tig welding.) And as with all other tig welding endeavors, make sure you select the right tungsten electrode and shielding gas for the job.
❯❯ If you’re going to be welding thicker pieces of aluminum, consider going with mig welding. As with stainless steel (see “Going with Stainless Steel” earlier in the chapter), aluminum can take a long time to weld if you’re working with thick pieces, and mig welding makes the process go faster. Be sure to keep your electrode wire clean, use a 30-degree leading travel angle, and go with pure argon for your shielding gas. (If those details are Greek to you, check out Chapters 9 and 10.)
❯❯ So what about using stick welding for aluminum? Well, it can be done, but I wouldn’t recommend it if you can go with tig or mig instead. Not many stick welding electrodes are available for working with aluminum, and maintaining good arc stability is tough. On top of that, you have to fight a constant battle to make completely sure that you keep the covering on the electrode extremely clean and dry, or you’re sunk. Bottom line: Avoid stick welding aluminum unless you simply have to do it.
Considering Other Metals
You can do a whole lot of welding with only steel, stainless steel, and aluminum, but you’ll inevitably want to branch out a little and work on some less commonly welded metals. Here’s a quick rundown of some of those metals, and you can find more information on them sprinkled throughout the other chapters of the book.
❯❯ Copper and copper-based alloys
Used for: Plumbing, electrical products, roofing, and as an additive to gold and silver to increase the strength of jewelry.
Welding process: You can use mig or tig welding for copper and copper-based alloys. Mig welding works in all positions and it’s especially useful for thicker pieces of copper. If you use mig for welding copper, be sure you use direct current electrode positive (DC+). Go with tig if you want to weld thinner pieces of copper – I recommend using direct current electrode negative (DC–).
❯❯ Magnesium
Used for: An alloy in steel. Makes steel resistant to abrasion, so it’s perfect for rock crushers, grinding tools, grinding mills, and so on.
Welding process: Use tig for welding thin pieces of magnesium-based alloys; use mig if the pieces are thicker.
Some magnesium-based alloys have high levels of zinc in them. Avoid welding those alloys if at all possible because it’s extremely hard to keep them from cracking.
❯❯ Nickel-based alloys
Used for: An alloy in stainless steel. Nickel in the 200 and 300 series stainless steels is the most resistant to corrosion.
Welding process: You can use any of the big three arc welding methods for welding nickel-based alloys. Stick welding gives you a weld that’s stronger than the base metal. (That’s good!) Tig welding a nickel-based alloy involves using a 2 percent thoriated tungsten electrode and argon as your shielding gas. You can tig weld a nickel-based alloy in any position. (If some of those terms look a little wacky to you, flip over to Chapter 7 for some gory tig welding details.) Finally, if you’re going to be mig welding a nickel-based alloy, plan to use a 50/50 mix of argon and helium for your shielding gas. Like tig, you can mig weld these alloys in any position.
PRECIOUS METALS
You may think it sounds crazy, but you can definitely weld precious metals like gold, silver, and platinum. Gold can be soldered (welded at a temperature below 840 degrees Fahrenheit) or brazed (welded at a temperature above 840 degrees Fahrenheit), and I recommend doing so with a gas torch – check out Chapter 13 for more on brazing and soldering. The same goes for silver. Platinum is a little different; oxyfuel (see Chapter 11) and tig are your best bets when welding platinum. Oh, and you may want to be sure you have a good lock on your welding shop before you start welding metals that cost thousands of dollars per ounce!
Chapter 3
Setting Your Sights on Welding Safety
IN THIS CHAPTER
❯❯ Making sure you have the right safety gear
❯❯ Understanding basic safety rules for welding
❯❯ Knowing how to prepare for and handle accidents and injuries
What’s the most important aspect of welding? The answer is simple: safety. What good does a beautiful weld and a job well done do you if you’ve hurt yourself (or others) in the process?
Many dangerous elements make up any welding operation. You use massive amounts of electricity to join metals (which are often sharp and heavy) through melting. You’re constantly at risk for electric shock, serious eye injuries, and burns. It’s not exactly a pillow fight, is it?
You can’t change the basic elements that make welding dangerous, but you can (and should, without fail) take every precaution to make sure your welding projects are as safe as possible. Your approach to welding safety should be complete and relentless; just one careless move or lack of safety preparation can result in serious injury or death.
In this chapter, I cover all the aspects of welding safety that you need to understand and remember when you get started as a welder. As I mention many times throughout this book, this chapter is really the most important one, and I hope you read it carefully and take its information to heart.
Welding safety is no accident! Be sure to take the precautions necessary to ensure your safety and the safety of those around you. You also need to make sure anyone who comes near your welding projects is aware of proper welding safety practices so that they can help keep themselves safe as well.
Gearing Up to Protect Yourself
A big part of welding safety is making sure you have the right safety equipment on hand for every job, and that’s what I discuss in the following sections. Figure 3-1 shows a welder in full protective gear; make sure you have all these items available before you get going on any welding project.
FIGURE 3-1: A welder wearing recommended safety gear, including ample eye protection.
Choosing eye protection
To protect your eyes from flying debris (usually metal), which you encounter plenty of if you weld regularly, make sure you wear safety glasses in your shop at all times. Make a habit of putting them on as soon as you walk in the door – that way, you’re always protected.
To fully protect your eyes from the damaging effects of ultraviolet welding rays, you need a welding helmet. These helmets protect your eyes (and the rest of your face) from damaging rays, and they include special lenses that allow you to see your work clearly without suffering eye injuries, which I discuss in “Shielding yourself from burns” later in the chapter. (Check out Figure 3-1 for a look at what a welder with a welding helmet looks like.)
You need to get a helmet appropriate for your particular welding work. New welders often buy helmets that don’t cover all their needs, or purchase ones that are far too heavy duty (and therefore expensive) for the projects they want to do. The following list explains the features of welding helmets that can help you figure out which helmet is right for you:
❯❯ Shade number: The lenses in welding helmets are rated according to shade number. Shade numbers for welding range from #8 to #14. The higher the shade number, the higher the amperage (the amount of electrical energy flowing through a circuit) you can use when welding without damaging your eyes. Most welding operations are carried out at shade #10, but if you get above 140 amps you must get a darker lens with a shade in the #12 to #14 range.
❯❯ Auto-darkening or passive lens: Many welding helmets now offer an auto-darkening lens that automatically increases the shade number to account for more-intense welding rays. The alternative is a passive lens, which is the older style of helmet that has a fixed shade number. Auto-darkening helmets are nice because you can see through the lens when you don’t have a live welding arc, so you don’t have to constantly take your helmet off and put it back on when you’re working on a project. However, auto-darkening helmets are much more expensive. Passive lens helmets are cheaper, but you’ll likely have to remove them and put them back on over and over while you’re welding.
❯❯ Comfort: Make sure you get a helmet with an adjustable headband that feels comfortable on your head and neck. The helmet should stay in place and shouldn’t pinch your head.
Welding helmets take a lot of abuse, but you don’t have to replace your helmet if it gets nasty or dinged up. You can always repair or replace parts of the helmet (lenses, shields, and headbands for example) instead of emptying your wallet on a new one.
Sunglasses don’t protect the eyes from welding rays. Don’t even think about using them as eye protection.
Make sure you do whatever you can to protect the eyes of others who may be near your welding projects. Ultraviolet welding rays are so powerful that they can penetrate through closed eyelids. If you have bystanders, make sure you say “Cover!” loudly before you strike an arc and get started welding. (You need to let your audience know beforehand what to expect when you say “Cover!”, of course.)
Keeping the right fire extinguisher on hand
With all the extreme heat and sparks created during a welding job, you shouldn’t be surprised if something catches fire at some point. Because fires are a very real threat, keep a fire extinguisher on hand at all times.
Four main types of fire extinguishers (shown in Figure 3-2) work on four different kinds of fires:
❯❯ Class A: Class A extinguishers take care of any fires that produce ash. These fires usually involve wood, cloth, or paper.
❯❯ Class B: Class B fire extinguishers are for fighting fires caused by flammable liquids, such as gasoline, oils, and paints.
❯❯
Class C: Electrical fires call for Class C fire extinguishers. Don’t use any water- or foam-based extinguishers on an electric fire, or you put yourself at risk of serious shock.
❯❯ Class D: Use Class D extinguishers on metal fires. Combustible metals like magnesium, potassium, and sodium are extremely flammable, and fires based on these materials are very dangerous. Class D extinguishers are best for these fires because the other classes often disperse a metal fire instead of putting it out, and that makes the situation worse.
You should keep a Class C extinguisher nearby when you’re welding, in case an electrical fire breaks out. I recommend also keeping a Class B on hand for oil fires.
In addition to fire extinguishers, keep a water source (a hose, for example) and a bucket of sand nearby when you’re welding. They can come in handy when you need to control ash and metal fires, respectively, without the need for special extinguishers.
The best way to avoid needing an extinguisher is to cut down on the flammability of your project in the first place. For example, you may find the need to weld a metal 55-gallon drum. (It’s a common welding task.) If so, take care to ensure that the drum doesn’t have residual flammable materials on the interior. Before welding, be sure to clean the interior with steam or a chemical cleaner.
FIGURE 3-2: Four classes of fire extinguishers.
Wearing protective clothing
If you’ve ever thought of yourself getting started on your first welding project wearing a pair of shorts, an old t-shirt, and a pair of flip-flops, think again. If you want to keep your body safe from the hazards of welding – especially burns – you have to always wear appropriate protective clothing.
Welding produces a huge amount of hot metal sparks and flying slag (molten metal). To keep your skin from being burned, choose clothing made from the right material. One of the best options is 100-percent wool, but it can be difficult to find and is extremely hot. (Some people are also allergic to wool.) I prefer 100-percent cotton, and it’s the most popular material used for welding clothing. The fabric should be thick (because welding rays can penetrate thin fabric and burn your skin like a sunburn) and dark-colored; black and dark blue are good options.
Sorry, but you can’t use that old polyester leisure suit from the ’70s when you’re welding. Synthetic fabrics like polyester, nylon, and rayon are unsafe for welding because they can melt and adhere to your skin when they get hot. And that definitely does not promote leisure.
Before welding, check to see that your clothes are free from oil and anything else flammable. They should also be tight fitting and free from holes and frayed or torn edges. Here are a few more clothing-related details to bear in mind.
❯❯ Shirts: Wear long-sleeved shirts only, and tuck your shirttail into your pants. If you wear a shirt with front pockets, make sure they have flaps covering them so that sparks can’t fall down inside. Keep your shirt sleeves rolled down at all times.
❯❯ Pants: Make sure your pants cover the tops of your shoes or boots so that sparks can’t get in.
❯❯ Gloves: Protect your hands with leather gauntlet gloves. Don’t wear cotton gloves at any time.
❯❯ Boots or shoes: Go with leather boots or shoes, and make sure they come up high on your ankle. Leather is the best option because it protects you from the hazards and heat created by the welding process. The tops of the shoes should be smooth so sparks don’t get trapped.
❯❯ Hats or beanies: You can buy a welder’s beanie to keep your hair from catching fire – not a bad idea.
❯❯ Leather jackets: A full leather jacket protects you from sparks and slag when you’re doing work in unusual positions, but many such jackets are very hot and heavy to wear. If a leather jacket is too hot and uncomfortable, you can buy leather sleeves and bibs only. These items are cooler and more comfortable, but they do leave your back unprotected.
❯❯ Leather aprons: These items protect your lap, and I highly recommend wearing one if you plan to sit down while welding.
❯❯ Spats: If you’re going to have a large amount of sparks and slag (the waste products that come from the flux) falling at your feet, you may consider getting some spats (shoe covers). Leather spats greatly reduce the risk of burns on your feet and damage to your shoes or boots.
Be careful what you have in your pockets when you weld. If you have a cigarette lighter or matches in your pocket during a welding project and a spark gets close enough, it can cause a fire in your pocket.
Watching health hazards: Using a respirator and Material Safety Data Sheets
Keep the Material Safety Data Sheets (MSDS) for every chemical and other potentially hazardous material in your welding shop on hand. These sheets describe all the properties of a given substance and include details on potential health hazards. Make certain that you and anyone who enters your welding area know the dangers of the materials on hand.
If you’re going to be working with metals or other materials that can produce toxic fumes – check your MSDS to be sure – you should wear a respirator. Simply welding or cutting certain materials can cause a welding plume, which is a mixture of dangerous gases, fumes, and smoke, and that’s definitely not the kind of thing you want to inhale if you’re interested in avoiding respiratory problems.
Figure 3-3 shows four types of respirators:
❯❯ On the top left, you can see a welder’s mask, which works to keep fumes out of your lungs.
❯❯ The mask on the top right has canisters that filter fumes and other hazardous materials while you’re welding. You can get different types of canisters to match the kinds of hazards specific to various welding projects.
❯❯ The basic dust mask on the bottom left offers the least amount of protection.
❯❯ The mask on the bottom right filters out particulate matter, so it’s a step up from the basic dust mask but doesn’t do much to protect you from harmful chemical fumes.
FIGURE 3-3: Four different respirator masks.
The metals you weld aren’t the only items that can cause harmful fumes – the substances that may coat those metals can also be hazardous. If you suspect that a piece of metal may be coated with paint or another kind of chemical that may generate dangerous fumes when heated up, be sure you remove that substance (with a chemical cleaner or grinder) before you weld.
In order for a respirator to be completely effective, you need to fit it with the right filter. Check your MSDS to find out which filter you need to protect your respiratory system from a given substance. You can also ask for help at your welding supply store.
Observing Basic Safety Rules
I’ve heard that some people are accident prone, but I just don’t believe that – especially when it comes to welding. Welding accidents occur when welders act carelessly, don’t read instructions, and don’t follow safety regulations. Every year, thousands of people are injured because they don’t take safety precautions while welding.
In many ways, welding safety is a habit. It’s the result of taking the appropriate precautions over and over, every time you weld. Following are a few safety tips that you should make a habit of in your welding shop:
❯❯ Don’t take chances while welding.
❯❯ Don’t use any welding equipment or supplies until you’ve thoroughly read the instructions and any additional safety information.
❯❯ Any time an accident occurs, be sure to fix the problem that caused it before doing any additional welding.
In addition to these very basic safety tips, you also need to be familiar with a few more-involved safety goals, and that’s what I cover throughout the rest of this section.
Keeping your work space clean
When it comes to your welding area, practice good housekeeping. Take the time before, during, and after a welding project to make sure the area is tidy and organized. Here are a few pointers to help you accomplish the goal of maintaining a shipshape welding shop:
❯❯ Designate a place for all tools, and when you’re done using a tool, be sure it goes back in the correct place. At the end of a welding project (or at the end of the day), clean all tools and inspect them for any damage that may have occurred while you were welding.
❯❯ Keep cables neat and free of knots. Nothing makes for a worse tripping hazard than messy tangles of cables.
❯❯ If you have any combustible items in your shop, be sure they’re stored away safely before you start to weld. (“Storing flammable liquids and gases” later in the chapter gives you the lowdown on proper safekeeping of such items.)
❯❯ Be sure your work area has adequate lighting. A well-lit workspace is less likely to become cluttered and disorganized.
❯❯ Keep all scrap metal out of your welding area.
❯❯ If a spill occurs, stop what you’re doing and clean it up immediately.
❯❯ When your waste or garbage container becomes full, take the time to go and dump it.
Checking for leaks
Your welding shop is bound to contain pressurized containers full of liquids or gases. Take special care to ensure that none of those containers (or the tools that you attach to them) has leaks. Checking for leaks is a simple process:
1. Mix one teaspoon of dish soap in a spray bottle full of water.
2. Spray the mixture onto any area of a pressurized container that is likely to have a leak.
Fittings and valves are usually the most likely sources of a leak.
3. Look and listen closely for bubbles.
If you see bubbles or hear a bubbling noise, that probably means you have a leak. If the bubbles are popping up near a fitting, use a wrench to tighten up the fitting. Then reapply the soapy water and check again for bubbles. If you see bubbles on or near a valve, it may be time to replace the valve.
If you’re using any oxyacetylene equipment (see Chapters 11, 12, and 13), you know when you have a leak if you smell garlic. Manufacturers now add a compound to the acetylene that makes it smell like garlic; if you get a waft of garlic smell and think you may have a leak, use the soapy water method I describe in this section to find out where the leak is coming from. (Of course, the garlic smell may also be the result of the pizza you had for lunch, in which case you may just want to grab a stick of gum.)
White thread seal tape can be useful for making sure that fittings and valves don’t leak, but be sure you never use the tape on brass fittings because brass fittings seal themselves.
Hoses are also common sources of leaks, so make sure to inspect your hoses frequently for nicks and burned sections. And please don’t try to fix your hoses with tape! Tape fixes aren’t reliable, and they don’t last very long. Figure 3-4 shows you what a leaking oxygen hose looks like.
Getting the ventilation right
Welding produces byproducts, and while you’re welding you can be exposed to a number of dangerous gases. These gases are created when metals are heated above their melting points, when certain electrodes (with special coatings) are in use, and when you don’t scrape or clean certain materials (paint, for example) off a section of metal before you weld it.
FIGURE 3-4: An example of a leaking oxygen hose.
If you want to stay healthy, you certainly don’t want to inhale those gases, so make sure your welding area is properly ventilated before you begin any welding operation. You can use natural ventilation if you have windows, doors, or garage doors in your welding shop that you can open safely to allow a breeze in. You can also utilize forced air movement with fans and blowers. For detailed information on how to ensure a suitable level of ventilation in your welding workspace, check out the welding-specific information provided on the Occupational Safety and Health Administration (OSHA) website at www.osha.gov/SLTC/weldingcuttingbrazing.
Proper ventilation is always important, but it’s completely critical when you’re welding metals that create particularly noxious, dangerous fumes. These metals include (but aren’t limited to) lead, zinc, and cadmium. Be sure to read your MSDS before using any new material.
Storing flammable liquids and gases
You may need to keep several flammable liquids and gases on hand in your welding shop, including acetylene, propane, and natural gas. You need to treat these materials with a great deal of care and respect because they can cause a huge amount of injury and damage in no time at all.
Store all flammable liquids in sealed containers and keep the containers in a flammable liquids locker like the one depicted in Figure 3-5. These lockers are made of metal and have a door that closes securely. You can buy a flammable liquids locker at your welding supply store or even a home improvement warehouse. As you can imagine, you don’t want to put the locker anywhere in your shop or welding area with a source of heat nearby.
FIGURE 3-5: A common flammable liquids storage locker, appropriately labeled.
A few common flammable welding gases (such as the acetylene, propane, and natural gas I mention earlier in the section) are compressed so that a large amount of gas can be put into a cylinder for controlled use. If you have these cylinders in your welding shop, be sure to store them far away from any heat source. Oxygen gas is also very dangerous when pressurized, so treat it with the same respect you would any other potentially hazardous gas.
Knowing your surroundings
You can prevent many different types of safety hazards in your welding shop simply by being aware of your surroundings and reacting quickly when something goes awry. When you’re working on a weld, you can easily get really focused and lose track of what’s going on around you, so you have to make a real effort to stay aware of your environment.
Pay close attention to any unusual smells or sounds. If you hear or smell something strange, check it out immediately – it may very well be a fire or something starting to catch fire. When you take a break from welding, either for a few minutes or for the night, take some time to look around the area to make sure nothing is burning or smoldering.
When you finish welding, double-check to make sure your welding equipment is turned off so that it doesn’t start a fire after you leave it unattended.
You should also take care to understand the materials you work with and give them the respect they deserve. Welding requires a number of harmful materials, and the short- and long-term effects of those items on your health can be severe. As I note throughout the chapter, always look at the MSDS for your materials so that you’re well informed of potential risks.
Don’t weld or cut anywhere near an area that may contain explosive or flammable vapors.
Welding also creates quite a bit of waste material that can harm your health. Electrode stubs (the 2- to 3-inch pieces of stick welding electrode that you can’t use) and scrap metal are two of the top offenders. Keep those things in safe containers until you can take them to your local metal recycling center. Some of the flux and dust that you generate when welding can be considered hazardous waste; read the literature that comes with your electrodes to understand what you’re up against. If you’re dealing with hazardous waste, don’t just throw it in the trash, on the ground, or in the toilet. Instead, dispose of it by taking it to your area’s hazardous waste disposal facility.
Protecting yourself from electric shock
Most welding equipment uses some sort of electrical power, so electric shock is a very real risk in the welding trade. Electric shocks can cause injury, death, fires, and explosions; here are a few tips to keep in mind in an effort to keep your risk for electric shock at an absolute minimum.
❯❯ Don’t allow electrode holders to touch wet gloves or wet skin.
❯❯ When using extension cords, be sure to plug the power tool you’re using into the extension cord before plugging the extension cord into the wall outlet. Then be sure you unplug the extension cord before you unplug the power tool.
❯❯ Be sure your extension cords don’t have kinks, knots, or nicks. Inspect your cords before you use them (every time), and get rid of the cord immediately if you notice damage.
❯❯ If a cable or cord feels hot to the touch when you’re using it, discontinue use right away. The heat means that the cord isn’t big or heavy duty enough for the amount of electricity you’re using, and that can be very dangerous.
❯❯ If any of the power tools or extension cords you’re using has a three-pronged plug and is missing one of the prongs, don’t use the tool or cord under any circumstances.
❯❯ Keep all power tools and cords dry at all times.
❯❯ If your power tools have worn or broken parts, repair or replace the broken parts immediately.
❯❯ If your power tools have keys, chucks, or wrenches attached to them, be sure to remove those items before plugging in or using those tools. They can create a hazard if they’re still inserted when the power tool starts moving or spinning.
❯❯ If a power tool’s housing is cracked, don’t use it.
❯❯ Make sure you provide a ground for any electric tool or device that requires grounding. (Read tool and equipment instructions thoroughly to determine whether you need to provide a ground.)
Shielding yourself from burns
You can suffer burns from two different sources while welding: hot metal and ultraviolet light. Burns caused by hot metal are self-explanatory, but you may not realize at first that you can also receive a burn from the ultraviolet light that’s a part of arc welding rays.
These rays are the same as what’s generated by the sun, except welding rays are much more concentrated. I’m sure as a child you heard to never look directly at the sun, right? Well, you certainly don’t want to look directly at a welding arc either. If you do, you can easily suffer burns on your retina, and you may lose part of your eyesight. These types of burns are called flash burns or arc eye, and as you can imagine, they’re extremely painful. You feel like you have something in your eye, and usually that’s caused by a blister on your eyeball (fun!). And just because you don’t feel the effects immediately doesn’t mean you haven’t been affected – they start about 8 to 24 hours after you look at a welding arc. Damage can occur even when the light is reflected off of a shiny surface.
To reduce the risk of burns while welding, minimize the amount of ultraviolet light reflected from the welding arc by painting the surfaces of your welding workspace (even the walls) with a flat, dark-colored paint (black and dark blue are good choices). You should also always wear a welding helmet and protective clothing, as I describe in “Gearing Up to Protect Yourself” earlier in the chapter.
Metal you’ve just welded will be hot, of course, so you need to make sure no one burns themselves on it. If you have to walk away from the weld, even for a minute, write “Hot” on the piece with a soapstone so passersby know not to touch.
Handle all hot metal with pliers to prevent burning your hands, even when wearing gloves. Another habit to develop is using the back of your hand (cautiously) to check to see whether something is hot. Put the back of your hand about a foot away from the potentially hot piece and move it slowly toward the piece. If it’s too hot, you’ll be able to tell when the back of your hand gets within two or three inches.
Maintaining your equipment
If you want to create the safest possible working environment for your welding jobs, you have to maintain your equipment extremely well. If your welding equipment and tools are falling apart, they’re just waiting to cause an accident, and almost all those types of accidents are preventable if you take care of your gear. Here’s how you can do just that:
❯❯ Perform a regular check of all equipment. Keep a list of all your equipment on a notebook or clipboard and do a monthly check through all of it to make sure everything is in good working order. Pay special attention to your electric equipment, hoses, cords, and regulators to make sure you don’t get shocked because of faulty equipment, and also to see that you don’t have a potentially harmful gas leak.
❯❯ Don’t hesitate to get professional repair help. If you notice something odd or potentially dangerous with some of your equipment and you don’t feel confident in your ability to remedy the problem on your own, take the equipment to a qualified service professional. Your local welding supply store should have someone on staff who can make those kinds of repairs, or be able to point you toward someone who can.
❯❯ If a tool or piece of equipment isn’t working the way it should, stop using it! Don’t fool yourself into thinking that you can “work out a bug” by just using a tool a little more.
Make sure the heads of your chisels and punches are ground round to keep the chips around the head from flying off when you’re using them. That’s a common but easily fixable problem.
Being Prepared for Injuries and Accidents
If you follow the safety guidelines I describe throughout this chapter, you greatly reduce the chances of an accident occurring in your welding shop. However, if an accident does happen, you need to know exactly what to do and how to handle it. That’s what I tackle in this section.
You should always have a telephone handy in case of an emergency, so you can quickly dial 911. It’s also a good idea to let friends and family know when you’re working in the shop so that they’ll notice if you don’t come back within a reasonable amount of time.
Equipping your first-aid kit
Keeping a first-aid kit in your welding shop is always a good idea so that you have the items you need if an accident occurs. Here’s what I recommend you include in that kit:
❯❯ Sterile bandages of various sizes
❯❯ Cold pack
❯❯ Sterile gauze in various sizes and lengths
❯❯ Burn gel or spray
❯❯ Antibiotic ointment
❯❯ Hydrogen peroxide
❯❯ Sterile compress dressings of various sizes
❯❯ Sterile gloves
❯❯ Tweezers
❯❯ Sterile adhesive tape
❯❯ Eyewash
❯❯ Antibacterial moist towelettes
❯❯ A protective airway mask
You should be able to find a first-aid kit that includes all these items at a hardware store or home improvement warehouse. I provide a useful example in Figure 3-6.
FIGURE 3-6: A well-stocked first-aid kit.
Knowing how to handle injuries
You may not be a doctor or an EMT, but if an injury occurs, you can still take some very basic steps to begin treatment and keep the injury from becoming more serious. Below I give you an overview of some of those steps.
❯❯ Bleeding and wounds: Apply steady pressure with a clean cloth or gloved hand. If the wound isn’t severe, clean it thoroughly and dress it with sterile bandages. If the wound or bleeding is severe, call 911 or go to the hospital immediately.
❯❯ Broken bones: Don’t move the injured body part or try to reset the bone. If any section of bone is protruding from the skin, cover it with a sterile, moist cloth. Call 911 or go to the hospital immediately.
❯❯ Electric shock: If you witness someone suffering from an electric shock, don’t touch them! You’ll become part of the circuit and be shocked, too. Instead, quickly turn off the source of the power. If the victim is unconscious, not breathing, or otherwise seriously injured, call 911 immediately.
❯❯ Gas inhalation: If you or someone in your work area inhales dangerous gases, get them into the fresh air and seek medical assistance immediately.
❯❯ Poison swallowed: If someone accidentally swallows a poisonous substance from your welding shop, call your poison control center or 911 immediately and follow its instructions. Take care to note the details of the poison that has been consumed. Don’t let the victim drink anything unless you’re directed to do so by emergency personnel or someone from the poison control center.
❯❯ Heart attack: Welding can be strenuous, and heart attacks while welding aren’t unheard of. If you or someone near you begins to experience severe pain in the chest, pain in the left shoulder, aching in the left arm, shortness of breath, or a bluish color in the lips or fingernails, dial 911 immediately.
❯❯ Clothing fires: Welding causes a lot of sparks, and those sparks can ignite clothing. If your clothing catches fire, strip it off immediately if possible. If you can’t strip it off quickly, you should stop, drop, and roll to put out the fire. Don’t run around – that fans the flames and makes the fire larger.
You can purchase a fire blanket to help extinguish small clothing fires or other fires in your shop. These blankets are usually made of fiberglass or wool treated with a fire retardant chemical, and you can buy them at a welding supply store or online.
❯❯ Burns (heat): Each one of the three different types of heat burns has its own treatment. (You can see examples of all three kinds of burns in Figure 3-7.)
● First-degree burns cause the skin to become red and tender but don’t break the surface of the skin. If you suffer a first-degree burn, run cold water over the area to cool it off and then cover it with a clean cloth and apply sterile bandages. Don’t use ice on a burn because it can damage the tissue.
● Second-degree burns occur when the skin is severely damaged; they commonly involve blisters and even breaks in the skin. If you suffer a second-degree burn, run cold water over it to decrease the pain and then cover the affected area with a sterile bandage. If a blister forms, don’t try to break it.
● Third-degree burns are the most serious type. If you suffer a third-degree burn, you likely feel very little pain in the affected area because the nerve endings have been destroyed. If you suffer a third-degree burn, seek medical attention immediately. If clothing is embedded in the burn, don’t try to remove it yourself.
❯❯ Burns (chemical): Some chemicals can cause burns; if your skin comes in contact with one of these materials, immediately flush the area with water. Remove all contaminated clothing and cover the burn with a clean, dry cloth. If the burn is serious, seek medical attention.
❯❯ Eye injuries: If a foreign object strikes or becomes embedded in your eye, place gauze over the eye immediately and secure it with a bandage. Don’t attempt to remove the object. Go to an eye doctor, call 911, or visit an emergency room as soon as possible. If a chemical comes in contact with your eye, flush out the affected area with warm running water right away and then place gauze over the injured eye and seek medical attention.
If you think you may have a flash burn on your eye, see a doctor immediately. You shouldn’t try any home remedies, but you can put a cold, wet washcloth over your closed eye to help ease some of the pain. (Flip to “Shielding yourself from burns” earlier in the chapter for more on flash burns.)
❯❯ Plume poisoning: If your welding area isn’t well ventilated and you’re not wearing a respirator, you can suffer from plume poisoning, which is sickness or injury that results from inhaling dangerous welding byproducts. If you accidentally inhale those substances, you should immediately get away from the plume and into some fresh air. Then seek medical assistance right away. For more on respirators, check out “Watching health hazards: Using a respirator and Material Safety Data Sheets” earlier in the chapter.
FIGURE 3-7: The three different kinds of heat burns.
Chapter 4
Setting Up Your Welding Shop
IN THIS CHAPTER
❯❯ Selecting and setting up your welding location
❯❯ Making sure you have all the necessary equipment
If you want to succeed with any welding endeavor, you need to cover two bases: location and equipment. You can’t get very far with welding – particularly good welding – if you don’t have the right kind of setup, from the building itself to the tools and other gear you need to equip the space properly.
Some folks who are new to welding think they can simply clear out a space in their garages, buy a welder from an online retailer at a deep discount, and start making high-quality welds in no time. Not so fast! You need to think through all the requirements necessary for a welding space that allows you to do good work and do it safely. And when you’re talking about welding equipment and tools, you need to make sure you have all the basics (and maybe a few extras as well).
In this chapter, I tell you how to get set up for welding. I start by filling you in on the details of how you can identify a suitable location for welding. No two welding methods or jobs are the same, but even with all that variety, all good welding sites share a number of characteristics that you need to maintain if you want to ensure a productive and safe working environment. After that, I move on to a discussion of welding equipment, which you need to choose carefully so you end up with gear that fits your welding needs.
Choosing a Location
You can’t find too many hobbies or jobs that are more versatile than welding. Welders with lots of experience are able to make welds in some pretty amazing places (underwater and in space, for example). But if you’re just starting to weld, you can get set up in a relatively simple, straightforward way. You don’t have to have a massive, state-of-the-art facility for your welding endeavor; you really just need to make sure your welding space has a few basic features, including the following:
❯❯ Adequate lighting: Like all other trades, welding requires ample lighting so that you can clearly see what you’re working on. Make sure your welding space has plenty of light, whether that’s natural, electric, or some combination of the two.
❯❯ Flame retardant floors and walls: Many welding tasks create sparks, so you certainly can’t fire up the old welding machine in a room with shag carpeting and wallpaper. Instead, try to find a space that has, for example, concrete floors and cinder block walls (or something equally resistant to catching fire).
❯❯ Large doors: If you’re going to be welding any large items, you need to be able to get them into and out of the welding area safely and smoothly. Keep in mind that you may limit yourself in terms of the range of welding projects you can tackle if you can’t fit certain items into the space. A large overhead or roll-up door is necessary if you want to work on bigger projects indoors.
❯❯ Sufficient electrical service: Welding machines and other equipment used in cutting, grinding, and welding can use quite a lot of electricity, so be sure that your welding location is properly serviced. Generally speaking, you should be in good shape if you have 220 single phase service (the kind of electrical outlets you use to plug in an electric clothes dryer) or 110 single phase service (the kind of outlets located all throughout your home, used for plugging in lamps and small electrical appliances) with 20-amp circuit breakers. (Those are some of the most common circuit breakers out there.)
❯❯ Ventilation: You can read more about safety-related issues like ventilation in Chapter 3, but for this part of the discussion, just make sure your welding space is properly ventilated so that you (and any other people nearby) don’t suffer any negative health effects from the gases and smoke that welding can produce.
Deciding how much space you need
The amount of space you need in order to weld safely and successfully is always important. Because of the potentially hazardous nature of many welding processes, you need to make sure you have enough space; otherwise, you put your health and the quality of your work at risk.
Many people who are new to welding assume that they can set up a little welding shop somewhere in their home. (A garage or shed is usually the first choice.) That can be okay, but only if the space you’re considering fits the criteria in the preceding section and also doesn’t compromise your safety. (Be sure to read Chapter 3 carefully if you have any doubts or questions about the safety precautions you need to take before you begin welding.)
Be sure that the space you’re welding in doesn’t contain any flammable material located within 35 feet of the actual welding area. That may sound like a large distance, but you may be very surprised (in an unpleasant way) how far sparks can fly when you’re making some welds.
When you’re considering a potential space for your welding work, think hard about the kinds of items you plan to work with. Is your space big enough to allow you to move those objects around without banging into other projects, your tools, or – worse yet – your body? Keep in mind that the equipment you’re working with may very well be heavy, sharp, and/or hot. Those aren’t the kinds of items you want to be trying to manipulate and move in a cramped environment.
Another important factor to consider is the amount of space your welding equipment takes up. Most welding machines – more about those later in this chapter – are only about three feet by four feet, but you may end up eating up quite a bit of space after you factor in all the other gear and supplies you need. Be sure to allow plenty of room for your equipment, or your welding projects may suffer from a cumbersome and disorganized workspace.
Contemplating indoor versus outdoor
Sometimes the welding project you’re working on dictates the location in which you’re forced to work. If you’re welding a big piece of equipment that has broken and become immobilized outdoors somewhere, you may very well be forced to do your welding outside. If that situation (or something similar) arises, don’t automatically think that it presents a difficult challenge. Welding outdoors can actually be just as enjoyable and productive as welding in an indoor welding shop, and in some cases even more so. Indoor and outdoor welding each have a number of advantages and disadvantages you want to bear in mind when you find yourself in a situation that allows you to make that choice on a particular welding project.
When you weld indoors, you often have the advantage of regulating the temperature in the building. That can be a huge plus, as anyone who has been forced to weld outside in the sweltering heat of summer can attest. You can also control the lighting to fit your needs and the needs of the job, and when you weld indoors, your equipment isn’t exposed to the damaging effects of the weather.
However, welding indoors isn’t all positive. No matter how big your welding space is, some jobs just don’t fit indoors. Welding inside a building can also be more difficult if you’re doing the kind of welding that produces an unusually large amount of smoke and dangerous fumes. Your indoor welding space has ventilation, of course, but chances are your indoor ventilation system isn’t as good at whisking away the fumes and smoke as a spring breeze can be when you’re welding outside.
As you can imagine, the biggest challenge presented by outdoor welding is the elements. The weather can wreak havoc on the quality of your work and the integrity of your equipment. Precipitation can make welding unnecessarily dangerous, and forget welding successfully when the temperature is below 40 degrees Fahrenheit if you don’t preheat the materials. And even sunshine, which is usually a pleasant part of welding outside, can pose a problem: Sometimes direct sunlight makes certain types of welding helmets function poorly. (Read more about welding helmets in Chapter 3.) Finally, if you’re welding outside where other people will be present, you really need to set up a safety screen so your audience’s eyes aren’t harmed by the welding process if they happen to look at it.
Equipping Your Welding Shop
You’d be hard pressed to find a skilled trade or craft that doesn’t require some specialized equipment, and welding is definitely no exception. But hey, you’re talking about joining metals, not making ham sandwiches, so I’m sure it comes as no surprise that you need some specific gear in order to get the job done right. You can get a look at some of the necessary equipment in Figure 4-1.
In this section, I let you know what kind of general equipment you need for a welding project. Keep in mind that plenty of other types of gear are necessary for certain kinds of welding, and I tell you about those tools and materials in the parts of this book that dig into the details of specific welding types. (For example, you need certain items for flux core arc welding that you don’t need for the other kinds of welding, and I cover those specific items in Chapter 9.)
FIGURE 4-1: A well-equipped welding area setup, this one for stick welding.
The most important welding equipment you’ll ever own is your safety equipment. I don’t cover that information in this section, so be sure to flip to Chapter 3 so that you understand everything you need to stay safe and healthy as you weld.
You have plenty of options when you’re looking to obtain your welding equipment. A lot of different manufacturers are producing tools and materials now; if you do a quick Internet search for a chipping hammer – one of the most basic welding tools – you find dozens of options from many different suppliers in a range of prices.
So which equipment is right for you? In many cases, you can let your budget be your guide; look around (at hardware or home improvement stores, on the Internet, in welding catalogs, and so on) at the various options and find some that fit both your needs and your price range. Then, to narrow your choices, read some online reviews of the various products and talk to knowledgeable salespeople at the retailers you’re considering. If you have friends, family members, or co-workers who weld, pick their brains about the tools and materials they use.
If you’re looking to buy some welding equipment and you’re worried that your budget isn’t going to cover all the items you need, don’t be afraid to investigate used options. You can find good quality used equipment from online retailers and also at auctions.
Making sure you have the basic hand tools
Some of the tools you need for your welding projects are basic hand tools. Several of these items are pretty common, so you may very well already have one or a few of them in your toolbox now. If you don’t, though, you’re going to have to get your hands on them, because you can’t do without them.
With hand tools used in welding, try to stick to metal (not wood or plastic) construction because of the heat and sparks involved. Metal tools hold up and perform better over the long run.
Following are the basic tools you need, some of which are shown in Figure 4-2:
❯❯ Ball-peen hammer: Ball-peen hammers are used for striking chisels and punches. They’re also handy for straightening metal. The rounded head is used for peening, which relieves the stress in a joint that you’ve just welded. You can pick up a good ball-peen hammer at a hardware store for around $15.
❯❯ Chipping hammer: A chipping hammer is a specialty hammer you use to remove excess material (called slag) from your welds. Chipping hammers come in a range of sizes, but they’re typically a foot long and weigh about a pound. If you’re buying a new chipping hammer, you can expect to spend between $10 and $30.
❯❯ Crescent wrench (12 inches): Keeping a 12-inch crescent wrench on hand when you’re welding is always a good idea. It fits the majority of the nut and bolt sizes you encounter in welding.
❯❯ Level: A level is necessary to make sure the pieces you’re welding are at the correct horizontal or vertical position and also to test the accuracy of completed projects. Make sure you have an extremely durable level because they take a lot of abuse.
❯❯ Pliers: You definitely need a good pair of pliers for welding, and the run-of-the-mill pliers most people have in their toolboxes don’t really get the job done. You need slip joint pliers (pliers that let you increase the range of their jaws) with compound lever action to handle hot metal. You can also use tongs. Depending on the size of the pliers and the number of bells and whistles involved, you can expect to spend anywhere from $7 to more than $20.
Pliers or tongs are great for picking up hot metal. Grabbing pieces of hot metal while wearing your leather welding gloves can be dangerous, but it also hardens the leather, making the gloves less effective (and less comfortable) over time.
❯❯ Soapstone or silver pencils: You can’t use regular pencils or pens to write on metal, so you need to use soapstone or silver pencils. You can find both at your local hardware store for only a few dollars.
❯❯ Steel square: The steel square is a durable tool that you can use to keep your project in square during assembly. It’s essentially a right angle made out of steel, with one side 16 inches long and the other side 24 inches long. The face side of a steel square has a ruler that marks whole, half, quarter, and eighth inches. The back side is divided into whole inches, halves, and quarters.
❯❯ Straightedge: A straightedge is a must for drawing straight lines, transferring measurements, and double-checking for straightness. After all, nobody wants a crooked weld.
❯❯ Tape measure: You have to be able to measure and mark your materials to cut at the right dimensions, so a tape measure is a must. Luckily, tape measures are one of the most common tools out there. You can handle most jobs with a 25-foot-long, 1-inch-wide tape measure.
❯❯ Vise grips: These wrenches are combination tools that function as pliers, wrenches, portable vises, and clamps. They aren’t intended to replace box-end wrenches because of the damage they do to the fittings you’re working on. Most people prefer to also have a pair of pliers (as mentioned earlier in this list) in addition to vise grips.
Never use vise grips on nonferrous metal, which is metal that doesn’t contain iron. Vise grips can cause quite a lot of damage to nonferrous metals.
❯❯ Wire brush: You use wire brushes to clean up welds after you’ve chipped away at them. I recommend getting a brush with a nice long handle. If you want to kill two birds with one stone, some manufacturers sell a combination chipping hammer/wire brush. You can get a good wire brush for $10 to $20.
FIGURE 4-2: A typical ball-peen hammer (a), chipping hammer (b), crescent wrench (c), level (d), steel square (e), and straightedge (f).
Choosing a welding table
You need a very sturdy, reliable surface to use as a foundation for welding practice as well as many of your welding projects, especially the smaller jobs. The best option is a welding table. Don’t try to use a normal table or work bench, because the wood or metal construction will soon be spattered with (and probably burned by) welding materials.
A good welding table includes a steel top and angle iron or sturdy pipe for legs. (Check out the welding table in Figure 4-3 to get a feel for what one looks like.) Your local welding shop can build you a welding table, or you can buy one at a hardware or home improvement store. The table size you need is determined by the size of the projects you plan to work on. I recommend getting a table that is ⅜ inch thick, with a top that is 36 inches by 48 inches. Expect to spend at least $50, and remember that after you get the hang of welding, you can make your second table instead of buying it.
FIGURE 4-3: A typical welding table.
Be sure that you can adjust the height of your welding table, or be certain before you buy it that you can be comfortable working at the table. You don’t want to have to bend down or stretch to use the table.
Selecting your welding machine
One of the most important pieces of welding equipment you buy is your welding machine, the apparatus that provides the energy you use to make your welds and complete your welding projects. The machines come in many types, sizes, and prices to fit the needs of any welder. You can find inexpensive machines for small shops and projects, and expensive, more powerful welding machines for big shops and huge projects.
One of the most important considerations you need to keep in mind when you’re deciding which welding machine to acquire is the type of welding you plan on doing. Welding machines are available for all the various types of welding: stick welding, mig, tig, and more. (You can read more about the various types of welding in Chapter 1, and in the chapters that make up Parts 2, 3, and 4, where I dive into the details of each welding type.)
Welding machine basics
Following are a few welding machine considerations that you can keep in mind when you start thinking about the type of machine you want to buy for your shop.
❯❯ Power source: Be sure to purchase a welding machine that fits the electricity power source that you have available. Most household or small shops have only single phase electricity available.
❯❯ Current: Welding machines are also sometimes classified by the type of current they require. Some machines use alternating current (AC), which is an electrical current that flows back and forth at regular intervals in a circuit. Other welding machines use direct current (DC), which flows in one direction.
❯❯ Duty cycle: Welding machines are rated on duty cycles, which indicate how many minutes out of ten the machine can run continuously at its maximum amperage output. (Most welding machines have an output of at least 200 amps.) A welding machine’s duty cycle is based on the manufacturer’s recommendation. For example, if a 200-amp machine is rated with a 60-percent duty cycle, you can use it continuously (and safely) for six out of ten minutes when you have it set to produce an output of 200 amps. You can get a constant potential (CP) welding machine that maintains a constant flow of electricity, which results in a 100-percent duty cycle.
❯❯ Material type and size: Some welding machines can weld just a couple of different types of metal, and others can weld a huge range. You should also keep the size (thickness) of the metals you’re welding in mind. If you’re welding materials that are less than 3/18 inch thick, most welding machines are powerful enough for you. If you’re welding thicker metals, you may want to get a machine that can produce more amperage.
New or used: Which welding machine is right for you?
After you understand the different types and classifications of welding machines (see the preceding section), you need to decide whether to buy a new machine or one that has been used.
The advantages and disadvantages afforded by new and used welding machines are similar to what you’d expect for most other types of machinery or equipment. New welding machines have no wear and tear, and you can often buy one with a warranty that helps protect you if the machine (or part of it) happens to break down soon after you buy it. Plus, new machines come with instructions that can be extremely helpful for a beginning welder, whereas used machines often no longer have the directions. On the downside, new machines are almost always more expensive than comparable used models. New stick welding machines typically cost at least $400, and mig welding machines are often twice that amount. A brand new tig welding machine can run you $1,200 or even more, depending on the size and features of the machine.
If you want to buy a new welding machine, you can find them at larger hardware and home improvement stores, welding supply stores, and through online retailers.
Used welding machines can be a good route for people who are just starting out with welding and don’t want to sink a lot of money in a new machine. You can find quality used welding machines for half the cost of a new machine. The good news is that most welding machines don’t wear out or become ineffective unless they’re mistreated or maintained poorly.
If you want to buy a used welding machine, you likely have three options:
❯❯ Auctions: Equipment or general auctions in your area can be a great source for used welding machines. Call ahead or look through auction listings to see whether any welding machines are up for bidding.
❯❯ Welding supply stores: Many welding supply stores offer incentives for welders to trade in their used welding machines when they’re looking to buy a new machine. The stores then sell the used machines, sometimes after carrying out some basic maintenance or making any necessary repairs to the machine.
❯❯ Individual sellers: If you have friends or family members who weld, you may ask them if they have a used welding machine that they’re interested in selling in the near future. That’s a good situation because it means you know the seller and are probably familiar with how he treats his equipment. (Although if that relative is your reckless Uncle Bob, you may want to think twice.) You can also find individual sellers looking to sell used machines in classified ads or through online listings.
If you’re interested in buying a used welding machine, be sure to require the seller to turn on the machine and produce a weld bead (deposit of filler metal from a single welding pass) for you. That basic operation check can help you avoid buying a worn-out or broken machine.
I know it seems obvious, but I’m always surprised at the number of people who buy a welding machine only to get it back to their shop and realize that the cables are too short for the projects they plan to work on. Be sure to check a welding machine’s cable length before you make a purchase!
Stick welding machines
Stick welding is one of the most widely practiced welding techniques. (You can read all about stick welding in Chapters 5 and 6.) One of the biggest reasons for stick welding’s popularity is the fact that it’s inexpensive – in fact, the equipment used in stick welding is the least expensive of all the electric welding processes. Stick welding machines include the machine itself, as well as the welding leads, ground clamp, and electrode holder (see Figure 4-4). That’s all! If you’re going to be doing any stick welding and you want to get your hands on a stick welding machine, the big choice you have to make is whether you want an AC or DC machine.
❯❯ DC: DC stick welding machines give you a continuous flow of electricity, and they make it easier to produce good welds because they give you a higher level of control.
❯❯ AC: AC stick welding machines have one very important advantage: price. AC stick welding machines are the cheapest welding machines you can buy, and they require little or no maintenance. However, they can be a little harder to work with than DC machines, especially for new welders.
FIGURE 4-4: Typical stick welding machine.
Mig welding machines
Mig welding machines are more complex than stick welding machines and include a welding gun, a spool of electrode, an electrode feeding unit, a power supply, cables, hoses, and a cylinder of shielding gas. (Flip over to Chapters 9 and 10 for more on those terms and other mig welding details.) You can check out mig welders at your local welding supply store, and you can also get parts (like refills for your shielding gas cylinders) there as well.
Mig welding machines (see Figure 4-5) are designed to weld a range of materials, including steel, stainless steel, and aluminum, to name just a few. However, if you want your mig welder to work on a variety of metals, you have to buy a few attachments. A mig welding machine without any additional attachments can weld steel, but if you want to weld aluminum, for example, you need a spool gun. Want to weld stainless steel? You need to change your shielding gas cylinder. Your local welding supply store can tell you all about what you need to change on your mig welder if you want to take advantage of the machine’s versatility and work on many different metals.
FIGURE 4-5: A mig welding machine.
Like the other types of welding machines, some mig welders are more powerful than others. The power you need is determined by the thickness of the metals you plan to weld. If you’re going to be welding materials that are more than ⅜ inch thick, consider buying a more powerful mig welding machine.
Some manufacturers are now producing mig welding machines that are self-setting. You just have to dial in the thickness of the material you’re welding and the machine sets the amperage level on its own. Pretty slick!
Tig welding machines
Tig welding machines are the most versatile of all the welding machines. With a tig machine (see Figure 4-6), you can weld all ferrous and nonferrous metals. Most tig machines allow you to change polarity (the direction in which the electricity flows), and that allows you to weld a wider range of materials.
FIGURE 4-6: A tig welding machine.
Tig welding machines and stick welding machines are somewhat interchangeable with a little modification. Stick welding machines can be used for tig welding if you buy and add on a number of attachments, and vice versa. If you’re planning on working on both tig welding and stick welding projects, I suggest buying a tig welding machine and also purchasing the attachments – a stick welding electrode holder with a lead and plug on the end that matches the machine – that allow you to use it for stick welding. It’s easier to make a stick welding machine from a tig machine than the other way around.
If you want to read more about the ins and outs of tig welding machines, check out Chapters 7 and 8.
Considering a few accessories for your welding shop
As with most types of equipment, you can add a few bells and whistles to your machine in the form of accessories. These items can make your machine easier to use, so you may consider whether one or more of the following are right for your setup:
❯❯ Cable holder: A hook mounted to the side of the machine that you can use to hold your lead and ground cables, cable holders help keep your work area more organized (and safer).
❯❯ Cup holders: I know it’s hard to believe, but you can now get cup holders that mount to your welding machine. Just make sure your drink has a lid.
❯❯ Storage: You can get small drawers for some welding machines now that can helpfully store the various small parts that you need when welding.
❯❯ Welding machine carriage: These carts have wheels that make moving your welding machine easier. They’re almost always made of steel, and you can buy one for about $200. That seems like a lot, but some welding machines weigh more than 100 pounds, and spending $200 for a cart is much cheaper than spending twice or three times that amount at the chiropractor’s office!
These accessories aren’t really necessary for you to own, but they are handy things to have. For information on even more tools and accessories that you may want for your welding shop, see Chapter 19.
In addition to the basic tools, welding table, welding machine, and welding machine accessories I discuss in the preceding sections, this section lists several other tools and pieces of gear you may want to buy and have on hand when you’re getting ready for a welding project or setting up your shop. You can find all these items at welding supply stores or hardware/home improvement stores.
❯❯ Air compressor: If you’re going to be using any pneumatic tools, you need a good air compressor. Cost: $160.
❯❯ Anvil: An anvil is a good tool to have around when you need to hammer or straighten out a large piece of metal. (It’s also useful, of course, if you’re a coyote and you’re trying to kill a roadrunner.) Keep in mind that you can also use a large, solid, secured piece of metal (a railroad rail, for example) in your shop in place of an anvil. Just don’t go pulling up train tracks to save money. Cost: $150.
❯❯ Creeper: A creeper (shown in Figure 4-7) is a small platform with wheels that you can lie down on and use to roll around. Creepers are helpful when you need to get up under something. Cost: $30.
FIGURE 4-7: A creeper.
❯❯ Drill press: I think having a good, small drill press on hand in the welding shop is extremely handy. Be sure you have plenty of good bits that fit the press. Cost: $100 to $1,000.
Don’t buy a drill press that’s too large or expensive for your needs. Bigger isn’t always better.
❯❯ Grinder: Grinders are useful for grinding down rough surfaces. If you get a grinder, make sure to also pick up some ferrous and nonferrous grinding discs that fit the machine. Cost: $85 to $125.
❯❯ Hacksaw: Hacksaws are extremely useful for cutting metal. Cost: $8 (includes a package of blades).
❯❯ Portable welding curtain: These items (see Figure 4-8) are usually made of vinyl, and they can help to shield bystanders from the dangerous rays created while welding. Cost: $10.
❯❯ Vise: Consider mounting a small vise to your welding table. It can be very helpful when you’re trying to work on small projects that are tough to manipulate while welding. Cost: $25.
❯❯ Wall clock: It may sound simple, but having a clock mounted on the wall is a much easier way to keep track of the time while welding than having to take off your gloves and push up your sleeves to check your watch. Welding is fun, and time flies when you’re having fun, so why not have an easy way to keep track of it? Cost: $3.
FIGURE 4-8: A standard portable welding curtain.
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