How safe are welding extension cords to use?

Purpose-made welding extension cords can bring a sense of portability to your welder. However, there are certain stipulations which you should follow when buying and/or creating your own welding extension cord. The welder (both operator and machine), length of cord, power supply, and many other details affect the safety factor. In short, welding extension cords—much like welding units—can be as safe or unsafe as they are built to be.

Most of us are familiar with how an extension cord works. Rather than limiting your work area to a certain distance around the power outlet, an extension cord extends the reach of the power supply. In many cases, extension cords are safe to use around the house, in the garage, and throughout the shop. That being said, welding extension cords follow the same concept, but have much more at stake than your typical household cord.

In this article, we’ll introduce you to the concept of a welding extension cord, what’s necessary to consider when purchasing one for your welding unit, the process by which you can make your own welding extension cord, and the various considerations you should account for. If you didn’t know much about extension cords, you’ll come away from this piece with a better understanding of how they work, without having to delve too deeply into the electrical side of things.

To start out, let’s run through the basics of what an extension cord does, and the various related terms you should know. From there we’ll build on what characteristics welding extension cords should have and finally, we’ll tell you how you can make a welding extension cord at home.

Understanding Extension Cords: A Basic Electrical Knowledge

Simply put, an extension cord allows electricity to flow from a power source to a singular unit, be that an angle grinder, a toaster, or in the case of this article, a welder. But connecting these two units comes with challenges and safety precautions, many of which are related to the fact that electricity requires a circuit to function.

Within this circuit, a ground is key to safe welding. Per Lincoln Electric’s website, the “purpose of connecting the equipment closure to ground is to ensure that the metal enclosure of the welding machine and ground is at the same potential.” This prevents the person welding from experiencing electric shock. Thus, having a ground built into your extension cord is first in the way of being safe.

Beyond staying grounded, you should also know a few more things about basic electrical circuits. Keep reading for a crash course—but don’t worry, there won’t be a quiz later.

Extension Cord Electrical Terms

Here are a couple other electrical terms associated with extension cords that you’ll want to understand before you make a trip to the store—or navigate to an online retailer.

• Voltage: Think of voltage as the capacity of electrical potential an object can take. To put it into context, your typical outlet is 110 volts. Electric clothes dryers are most commonly the only household devices that require a 220 volt connection. Manufacturers will denote what voltage their welders require, though some can work off both 110 and 220 volt connections.  
• Gauge: The measurement of how thick a wire is, gauge works in the opposite way you think it might. Thicker wires have a smaller gauge measurement, though they carry large amounts of electricity. For example, #3 gauge wire is much thicker than #12 gauge. Typically, most extension cords are anywhere from #8-#12 gauge. Gauges are also accompanied by a second number, which specifies exactly how many wires are in the protective jacketing. Ideally you want more wires and a low gauge to handle a large flow of electricity.
• Amperage: Electricians use amperage to describe the flow of electricity. Most extension cords can handle amperage ratings of 30-50 amps. If you are welding a lot or have a large welder, we recommend purchasing (or building) a heavy-duty extension cord that can handle the amperage of your welder without worry.
• Watts: Multiply volts times amps and you’ve got your wattage. When you’re looking at extension cords, this is useful to know because you can figure out which is best for your situation.

Now that you understand a bit more about all the electrical knowledge behind extension cords, let’s take a closer look at the difference between everyday extension cords and those you’ll want to use for welding.

Extension Cords vs. Welding Extension Cords

If you were to purchase a standard extension cord and plug it first into the wall and then into a fan for example, whenever you turn that fan on, the power would flow from the outlet, through the extension cord, and into the fan, powering it. Though that seems like elementary knowledge, it’s the basis upon which welding extension cords and the standard kind differ.

Most devices that require power have more or less a standard flow. Welders, however, must vary the flow in order to melt metals and join work pieces. While you control these settings on a welder itself, rather than at the power source, the extension cord that brings the supply of power must accommodate those settings. That’s why voltage, gauge, length, and durability all factor into what makes for a safe welding extension cord. It’s all in the name of safety.

Characteristics of a Safe Welding Extension Cord

Safety should be priority number one when searching for a welding extension cord. The safer you can make your welding environment, the more fun you’ll have! A safe welding extension cord finds value in accommodating the power draw of your welder while staying within the limits of the wire transmitting the power. In short, “you want to buy a cable that is fit for purpose, industry standard and safe to use.”

You want to pair the extension cord with your welder—whether it’s the one you own now or in the future. As WelderStation.com recommends, you “should always look for industry standard cords in the first place and check the specs carefully to make sure it is suitable. You want a stable energy transfer,” because it’s your welding process you should be focusing on, not the likelihood of being shocked.

The risks of not choosing the right wire are severe. For instance, if “you have the wrong gauge wire there can be a problem with voltage drop and you can end up overheating the wiring and your welder and causing damage.” You can also blow a fuse, start a fire, or worst of all, succumb to the powerful electric shock. Any old wire won’t do; you really need to research and make sure the extension cord you choose will keep you safe as you weld.

As we mentioned before, voltage, gauge, length, and durability either make or break a welding extension cord. Match the voltage of your power source, whether it’s 110 or 220. Buy thicker gauge wires in larger quantities to accommodate the flow of electricity to your welder. Find the appropriate length for your work space. And finally, invest in durable cables and plugs that will keep you in the welding shop and money in your pocket.

Buying vs. Creating Welding Extension Cords: Pros and Cons

So with all this in mind, the question lies before us: buy or create welding extension cords?

Buying Pros

Let’s consider purchasing welding extension cords first. It seems like the easiest way to do things, provided you’ve done your homework and know what you’re looking for. Online retailers aplenty will sell you welding cables. Plus, you won’t have to spend your valuable time making them. Cost typically hits your wallet at anywhere from $30-$100, though some can tip over that $100 mark. And if something goes wrong, there’s usually a manufacturer’s warranty you can take advantage of.

Buying Cons

At the same time, you could find it’s cheaper to make your own extension cords. Really it depends on what materials you have at your disposal, your skill, etc. And while many companies might make you a custom welding extension cord, your options are limited—and your price goes up quickly, too.

Creating Pros

But what are the advantages of making your own welding extension cord? Customization allows you to get the job done how you want to. You can mix and match materials to fit your needs. And depending on how your electrical skills are, you could rig something up pretty quickly and have yourself welding in no time.

Creating Cons

Then again, there are quite a few hurtles that keep most people from creating their own extension cords. Fabricating a custom welding extension cord could potentially cost you more in the long run. Sometimes sourcing parts isn’t possible to do locally either. If you plan on using the homemade extension cord in a business setting, it could interfere with your insurance if problems arise. There are plenty of other reasons to steer clear of making your own welding extension cord. As WelderStation advises, “there are various online tutorials for doing just this but you have to ask yourself if it is worth the risk.”

If you’re considering making your own extension cord, keep reading. Note that the processes we describe and the methods we suggest are NOT meant as guidelines or any other form of instruction. If you plan on making your own welding extension cord, you do so at your own risk.

How to Make a Welding Extension Cord

The first step in creating your own welding extension cord is gathering the right materials. We’ve made a convenient shopping list for you below:

• Outlet: Be sure the outlet you purchase coincides with the design of the cord on your welder. Don’t buy a 2 prong outlet if your welder requires 3.
• Connector: Check to make sure the connector you’re planning on buying will work with either a 110 or a 220 volt outlet. Again, align the posts between the connector you buy and the outlet you’ll plug into in order to draw power.
• Wire: Look for the proper gauge and number of internal wires you need for your application. DIYWeldingPlans advises, “The longer you are from your power supply, the thicker the diameter of wire you should purchase. For more help with selecting the right gauge wire to use for your welder’s extension cord, the guys who work in the electrical section at your local home improvement store should be able to help.” Oftentimes it’s better to have more wire than you need in case your measurements or setup changes.

You’ll also need needle nose pliers, a razor blade, wire cutters, and Phillips and flathead screwdrivers. A flat surface to work on and good lighting are helpful as well.

Assembling Your New Welding Extension Cord

Now that you’ve got your materials gathered, the next step is to start assembling both your connector and your outlet. Most of the time these two items will be sold separately. Make sure you pick up the right configurations for your setup. Note: if you own a dual voltage welder—that is, one that can work off both 110 and 220 volts—make a set of welding extension cords for both. Just don’t mix up your connectors and welders!

Once you’re ready to connect your wires to both the connector and outlet, choose one to begin with. For our tutorial, we’ll begin with the connector. Open the connector box and measure the length of wire you’ll need. Sometimes it’s helpful to put the wire up to the entire length of the box and then make a mark with your razor blade. Remember to only cut the protective sheathing so that you can get to the wires within. Next, you’ll want to cut back the individual sheathings on each wire. You’ll be wrapping the bare wires around their corresponding posts. It’s critical to your safety at this point to make sure you connect the ground wire to the ground plug. Once you’ve connected each of the wires, you’re ready to close up the connector box and move on.

The outlet works in a similar way, from removing the protective sheathing surrounding both the bundle of wires together and each individual wire after that. Connect the bare wires to their proper terminals and then button up the outlet.

And there you have it! You now have a brand-new welding extension cord made with your own two hands.

To Create or Not to Create

The decision to make your own welding extension cord can be a risky one, but rather rewarding, too. We recommend reading through these electrical safety tips for welding before you begin working on your own welding extension cord. Understand the process before you begin to ensure a higher rate of success. However, there are some that might read this and think, “I’ll just go ahead and buy welding extension cords.” TheFabricator.com supports your decision in that case, advising, “Investing in a handful of high-quality, thick-gauge cords in different lengths is money well spent. Protect your tools, protect your shop, protect yourself. Don’t fight the power.” Whichever route you choose, use caution, be smart, and just remember: we want you to live to weld another day, so stay safe!