Meld Metals with Welding and Brazing

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Oxygen/acetylene torches and hoses include standardized fittings. This means the same set of torches can hook up to a variety of tank sizes. You can get sets ranging from small, portable tanks that fit into a carrying caddy to large, semi-stationary tanks meant for use in a workshop. All but the smallest tanks are available as refillable rental units. You pay an annual leasing fee for the tank, plus the cost of whatever gas you use.

ELECTRIC ARC WELDERS

Electric arc welding machines use an electric arc to create heat — not a flame. They include a grounding cable that clamps to the metal part to be welded. The machine passes a powerful electric current through another cable to the welding tool. When the tip of the tool gets close enough to the grounded metal part, electric current leaps (arcs) from the tool, through the metal part and back through the grounding cable to the welding machine. This current flow, the arc and the resulting heat are the heart of all electric welding processes.

Two basic kinds of arc welders exist: stick-type and wire-feed. Stick-type electric arc welders are extremely effective. Economy, a long history and strong welds are why stick welders are found in thousands of garages and farm workshops.

As in gas welding, stick welders deposit new metal into the weld area to fill gaps and boost strength. In fact, the word “stick” refers to the consumable welding rod, which you clamp into a hand-held welding tool. Electric welding rods come in numerous diameters and compositions designed for different applications, but in every case the metal rod is covered with a coating called flux. The flux coating vaporizes during use, creating a shield of inert gas that protects the weld for the few seconds that it remains in a molten state. Without this protective gas, the weld would oxidize rapidly while hot, ruining its strength and appearance. The most useful general-purpose stick welders require a 230 volt/50 amp circuit, and you can get a basic set of equipment for less than $300.

You simply drag the tip of the welding rod over the weld area to strike the arc. Skill in stick welding comes from learning how much electric power to dial into your machine for various situations, plus the experience required to learn to control the welding rod. The rod’s angle, its distance from the metal and the speed of its movement all have a bearing on success.

When I learned to weld 25 years ago in high school shop class, we used all the main welding processes. But right from the start, my favorite machine was the wire-feed arc welder. Back then, the cheapest wire-feed machines cost thousands of dollars and were designed exclusively for industrial use. Recently, however, small, lightweight wire-feed welders have hit the market. These new models do the same work as the old industrial machines, at less than 15 percent of the cost. You can buy an outfit for less than $350.

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