How To Weld Metal For Beginners | How To Weld Metal At Home For Beginners - A Learning Guide In 2020

 

Choose your method

There isn't one welding process suitable for all applications, so you need to consider these factors: the type and thickness of the metal you're welding, how big the job is, whether you're welding indoors or outdoors, what you want the welds to look like, and your budget.

The most widely used form of welding today is electric arc welding, in which an electric arc melts an electrode (welding wire, for instance) and partially melts the base metal. When the molten metals cool, the parts fuse. There are different arc welding types, but we're going to concentrate on MIG (inert metal gas). It's the most comfortable type to master, especially if you're teaching yourself a form of wire-feed welding.

Metal Inert Gas (MIG)

Uses a welding gun that continuously feeds wire from a spool when the operator presses the trigger. Along with the wire, the weld gun simultaneously supplies a shielding gas that protects the metal from impurities in the air. MIG yields cleaner, better-looking welds than stick welding.

Buy your equipment

Welder

The welder is your biggest ­expense, so don't cheat yourself—a cheap welder will only frustrate you and make learning more difficult. A wire-feed welder uses ordinary household current to produce an extremely hot, high-energy electric arc. Inside the machine is a small motor-driven spool of welding wire (the electrode). The wire is fed down a hose to a trigger-activated welding gun. When the operator touches the wire against the base metal, the arc melts the wire and partially melts the base. In MIG welding, as long as the trigger is down, the gun keeps feeding wire and gas.

The Lincoln Electric Power MIG 210 (above) is the new technology for a great price: At 120-v or 230-v, it allows an ambitious beginner to MIG-, TIG-, and stick-weld. It costs $999.

At $767, the Millermatic 141 (below) is an excellent introductory option. It's a 120-v wire-feed welder that can be used to weld thin aluminum and steel between 24-gauge and 3/16-inch.

Tip: Your welder also has a work lead coming out of it. This is an electrical cable with a clamp on the end that attaches to the base metal and completes the electrical circuit required to weld. If dirt, rust, or paint interferes with the lead's contact, your weld quality will suffer.

Welding wire

A wire is relatively inexpensive. A simple rule of thumb is to use a thin welding wire on thin sheet material and increase the wire diameter as the ­material's thickness increases. A welder takes at least two different diameters of wire.

IT'S ALL SURPRISINGLY ­INTUITIVE

The owner's manual for the machine tells you what it takes, and they're usually instructions on the flip-up panel on the machine's side. It's all surprisingly, ­intuitive.

Gas

Buying the right shielding gas is essential, so make sure you know what type of job you plan on tackling. You can pick up a reusable tank of gas from your local welding supplier. The psi will vary depending on the type of torch you're using and how deep you want your welds, but generally, you'll stick to between 15 and 25. As for the gas mixture, a home hobbyist with a wire-feed welder can usually get by with 100 percent CO2 shielding gas. For

Welding cart: Wire-feed welders can weigh up to 75 pounds, so build or invest in a welding cart to increase portability.

Awl or carbide scribe: to mark cut lines.

Right-angle grinder: for grinding, beveling, and flattening welds, as well as for surface preparation.

Miter clamp or magnet square: to secure joints.

Chipping hammer and wire brush: for cleaning up slag and spatter.

Welding pliers: to trim welding wire and remove spatter from the welding-gun nozzle.

You want an auto-darkening helmet: The light generated by any arc-welding process is incredibly bright, and it will burn your eyes if you're not wearing a helmet. For years traditional welding helmets had a permanently darkened viewing shade, but that meant you had to flip your mask up whenever you weren't welding. New auto-­darkening helmets protect against harmful light emissions by automatically darkening their clear lens to a preselected shade in milliseconds, using LCD technology in their glass. Each helmet also has controls to personalize settings.

Prepping your weld

Ready the metals

Use a wire brush and acetone to remove oils and dirt. If you need to cut the metal, mark a line with your awl or carbide scribe, and cut along it with a metal-cutting chop saw, a hacksaw, or a grinder with a cutoff wheel.

Grind the edges

But only the ones you plan to join and use a right-angle grinder. This is called chamfering. A chamfer is a bevel between the adjoining edges of two material pieces, typically at 45 degrees. This creates a space for the filler and provides greater structural integrity to your weld. Doing this for butt joints, especially, is a good idea.

THINK OF THE WELDING MOTION LIKE A GOLF SWING—YOU WANT AS FEW MOVING PARTS AS POSSIBLE

Position the metals

With your miter clamp or magnet square, secure the joints to keep the pieces of metal in the same plane before you begin the weld.

Tip: You are dealing with sparks, fire, and molten metal, so don't start welding before putting on a welding jacket or apron, leather gloves, and a helmet. If you want to save money, a good-quality long-sleeve cotton work shirt can stand in for a welding jacket. Don't forget your work boots (no sneakers), and remove jewelry from your wrists and neck. When grinding, put on safety glasses and a full-face shield. Keep an ABC fire extinguisher nearby too.

Body and hand position

Think of the welding motion like a golf swing—you want as few moving parts as possible, and you want the motion to be fluid and repeatable. When possible, hold the welding gun with two hands, or use your off-hand wrist to guide the hand holding the welder (think of a billiards shot). With the welder off, do a dry run to make sure your positioning is good. The steadier your hands, the better the weld.

Tack welding

Before starting, check your gun. The wire electrode should stick out between 1/4 and 3/8 inch. Make sure the nozzle is clear of spatter and that the wire tip is clean. Then make a few tack welds, just enough to connect the base metals, along the joint.

The final bead

After you've tacked the metals into place, you can lay down your final weld beads. Keeping the weld gun at about a 75-degree angle to the base, move slowly from left to right (if you're right-handed), spending one to two seconds laying down each bead and maintaining a constant arc length. Don't concentrate on the bright arc. Look at the edge of the weld puddle, and when you reach the end of your weld, pull the electrode back from the metal and allow it to cool.

Grinding your weld

If you don't care how your weld looks, or if it's on a piece of metal that won't be visible when your project is completed, you can skip this step because you are done. Congratulations—you've made your first welds. Work on perfecting your technique on scrap metal. Welding is a lot like playing the guitar: It's not hard to do it a little bit, but to become proficient, you need practice, practice, practice.

Flush-grinding welds

For a smooth finish, use a 36-grit grinding wheel ­attached to your right-angle grinder to grind along the weld path, not across it, for uniformity. Go slowly. If you grind through your weld, you'll have to start over. When grinding, you should see only orange sparks. Blue means you're pushing too hard. Once you've ­finished, grab a zirconia flap disc for precision shaping and finishing.