Match the Welder to the Work
There are several common types of electric welding machines, and they can vary greatly in price range and features. Which one is right for you depends on your budget, skill level, and type of projects you plan to use it for.
Deciphering the technical jargon necessary to choose a welding machine can be a daunting task. However, there are essentially only a few welding systems, and with a basic understanding of how each one works, your search may be easier than you expect.
The amperage of a welding machine determines the thickness of metal you can weld (a common guideline is 1 amp for every .001 in. of steel). The duty cycle is the percentage of time that a machine can run at a specific amperage without overheating.
Some welding machines are designed to work on a 20-amp, 120v household circuit, allowing you to weld just about anywhere. If you do a lot of continuous welding, you may need to splurge for one of the higher voltage machines with a higher duty cycle. If you expect to do a lot of job-site work in locations without reliable access to power, engine-driven welding machines are another option. One thing to note is that many modern welding machines are compatible with more than one voltage.
All welding systems need to do three essential things: create an electric arc to melt metal, protect the molten metal from oxidation, and feed filler metal into the weld. Here’s a rundown of how each type of system works and what it’s best suited for.
This simple, affordable welder has a handle that holds a consumable electrode (called the stick or rod) that melts and becomes part of the weld as you drag it across the surface of your workpiece. Each electrode is coated with flux, a material that protects and cleans the weld as it melts. The flux leaves behind a coating called “slag,” which may need to be cleaned up. Stick welding is slower than other types, but because of the flux coating, stick works better in windy conditions where shielding gas would be prone to blowing away from the tip and on rusty, oily, or dirty metal. Many types of specialty electrodes are available, making stick welding ideal for joining dissimilar metals or resurfacing hardened parts on excavators and farm equipment. Entry-level stick welders cost between $200 and $300.
If you’re looking for precision, a tungsten inert gas (TIG) welder is for you. With a small electric torch in one hand, a filler rod in the other hand, and an amperage- adjusting foot pedal below, you have constant control of all of the variables that make a weld happen. TIG welding requires more skill and concentration (and more time) than just about any other type of welding, but results in beautiful joints in virtually any type of metal, and needs little to no finish work. Other types of welding may be okay for some architectural metalwork, but intricate or delicate pieces may require or be improved by a TIG welder. Because of the level of control it offers, TIG is mandated in some fields, such as industrial pipe fitting and high-tech manufacturing. TIG welders start around $500.
Popular because they are versatile and easy to use, metal inert gas (MIG) welders feed filler wire (steel, stainless steel, or aluminum) and shielding gas into welds via a trigger-operated gun. The filler wire doubles as an electrode, providing a path for electricity to jump to the workpiece and melt it. MIG machines quickly lay down welds on anything from thin sheet metal to thick steel plates. With experience, you can make clean, attractive joints, but welds on decorative projects typically require some grinding and finishing. Most MIG welders also allow you to run flux-core wire through the gun as a substitute for shielding gas. The flux allows the machine to excel in dirty or windy conditions, much like a stick welder, making it a great option for job-site work or machinery repairs. Flux-core welding makes a lot of smoke, though, and it leaves a crusty layer that may need to be chipped and wire-brushed off as you go. It also doesn’t make as good-looking welds as MIG or TIG welding. The most basic MIG welders can be found for $200 to $400.
Modern machines handle multiple processes
Welding machines that do only one type of welding are becoming less common. Multiprocess machines, like Lincoln Electric’s Power MIG 210, are capable of MIG, flux-core, stick, and TIG welding right out of the box. At about $1250, this machine is worth considering—once you own a welding machine, not only will you want to use it, you’ll begin to find uses for it everywhere you look. Beyond the Lincoln Electric and Miller machines shown here, look at welders from Hobart, Victor, Forney, and Lotus.
This overview of electric welding machines originally appeared in the article Metalwork for Builders.