The arsenal of welding arsenals available to combat metal repair work has grown exponentially over the years, including the welder’s alphabetical list.
If you are over 50, you have probably learned how to weld with a SMAW (Shielded Metal Arc or Electrode) welding machine.
The 1990s brought us the convenience of MIG (metal inert gas) or FCAW (flux-cored arc welding) welding, which caused many buzzers to retire. More recently, TIG (tungsten inert gas) technology has made its way into agricultural stores as an ideal way to fuse sheet metal, aluminum and stainless steel.
The growing popularity of multi-purpose welders now means that all four processes can be used in one package.
Below are short welding courses that will improve your skills for reliable results, no matter what welding process you use.
Jody Collier has dedicated his career to welding and welder training. His websites Weldingtipsandtricks.com and Welding-TV.com are filled with practical tips and tricks for all types of welding.
The preferred gas for MIG welding is carbon dioxide (CO2). Although CO2 is economical and ideal for creating deep penetration welds in thicker steels, this shielding gas can be too hot when welding thin metals. That’s why Jody Collier recommends switching to a mixture of 75% argon and 25% carbon dioxide.
“Oh, you can use pure argon to MIG weld aluminum or steel, but only very thin materials,” he said. “Everything else is awfully welded with pure argon.”
Collier notes that there are many gas mixtures on the market, such as helium-argon-CO2, but sometimes they are hard to find and expensive.
If you are repairing stainless steel on a farm, you will need to add two mixtures of 100% argon or argon and helium for welding aluminum and a mixture of 90% argon, 7.5% helium and 2.5% carbon dioxide.
The permeability of the MIG weld depends on the shielding gas. Carbon dioxide (top right) provides deep penetration welding compared to argon-CO2 (top left).
Before arcing when repairing aluminum, be sure to thoroughly clean the weld to avoid destroying the weld.
Weld cleaning is critical because alumina melts at 3700°F and base metals melt at 1200°F. Therefore, any oxide (oxidation or white corrosion) or oil on the repaired surface will prevent penetration of the filler metal.
Fat removal comes first. Then, and only then, should oxidative contamination be removed. Don’t change the order, warns Joel Otter of Miller Electric.
With the rise in popularity of wire welding machines in the 1990s, the tried and true beehive welders were forced to collect dust in the corners of shops.
Unlike those old buzzers that were used only for alternating current (AC) operations, modern welders operate on both alternating current and direct current (DC), changing the welding polarity 120 times per second.
The benefits offered by this quick polarity change are enormous, including easier starting, less sticking, less spatter, more attractive welds, and easier vertical and overhead welding.
Combined with the fact that stick welding produces deeper welds, it is great for outdoor work (MIG shielding gas is blown away by the wind), works effectively with thick materials, and burns through rust, dirt, and paint. Welding machines are also portable and easy to operate, so you can see why a new electrode or multi-processor welding machine is worth the investment.
Joel Orth of Miller Electric offers the following electrode pointers. For more information visit: millerwelds.com/resources/welding-guides/stick-welding-guide/stick-welding-tips.
Hydrogen gas is a serious welding hazard, causing welding delays, HAZ cracking that occurs hours or days after welding is completed, or both.
However, the hydrogen threat is usually easily eliminated by thoroughly cleaning the metal. Removes oil, rust, paint and any moisture as they are a source of hydrogen.
However, hydrogen remains a threat when welding high-strength steel (increasingly used in modern agricultural equipment), thick metal profiles, and in highly restricted welding areas. When repairing these materials, be sure to use a low hydrogen electrode and preheat the weld area.
Jody Collier points out that spongy holes or tiny air bubbles appearing on the surface of a weld are a sure sign that your weld has porosity, which he considers the number one problem with welding.
Weld porosity can take many forms, including surface pores, wormholes, craters, and cavities, visible (on the surface) and invisible (deep in the weld).
Collier also advises, “Let the puddle stay molten longer, allowing the gas to boil out of the weld before it freezes.”
While the most common wire diameters are 0.035 and 0.045 inches, a smaller diameter wire makes it easier to form a good weld. Carl Huss of Lincoln Electric recommends using 0.025″ wire, especially when welding thin materials 1/8″ or less.
He explained that most welders tend to make welds that are too large, which can lead to burn-through. Smaller diameter wire provides a more stable weld at lower current making it less prone to burn through.
Be careful when using this method on thicker materials (3⁄16″ and thicker), as 0.025″ diameter wire may cause insufficient melting.
Once just a dream come true for farmers looking for a better way to weld thin metals, aluminum and stainless steel, TIG welders are becoming more common in farm shops thanks to the growing popularity of multi-processor welders.
However, based on personal experience, learning TIG welding is not as easy as learning MIG welding.
TIG requires both hands (one to hold the heat source in the sun-hot tungsten electrode, the other to feed the filler rod into the arc) and one foot (to operate the foot pedal or current regulator mounted on the torch) Three-way coordination is used to start, adjust and stop current flow).
To avoid results like mine, beginners and those looking to hone their skills can take advantage of these TIG welding tips, in the words of Miller Electric consultant Ron Covell, Welding Tips: The Secret to TIG Welding Success.
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