You're about to take the plunge and buy your first wire feeder welder, and you don't want to waste your money on a toy that goes out in the trash in a few weeks. You are probably quite comfortable building things out of wood, but always wanted to go steel. You'll probably want to run it with a 115 volt input, so it's very portable, but maybe upgrade to 230 volt input machines with the option to weld thicker material (over ¼ " ) is a valid point. You think the decision-making process is over when you are struck by another question - what welding process will you use? GMAW (MIG) or FCAW (flux-flux-cored)? If you are Like most novice welding operators, you may be confused as to the difference between these two choices. The best answer depends on 3 things. First, what you weld. Second, where do you weld it. And third, the finish surface of what you are soldering. We will help you decipher between the two processes, then describe the pros and cons of each and conclude by giving you some usage tips. Ultimately, we hope to help you choose one. solution that gives you will provide the best results for your application. The suggestions here are conservative and should be achievable for a beginner. Welding is a skill and an art about 95% can be learned to do. Very few baseball players are able to hit more than .350 in the majors. Very few welders have the skills to make perfect welds. Good eye / hand coordination and a steady hand are essential. The Arc Training Time is the only instructor who will teach you how to properly set up the machine. With basic motor skills, practice, and patience, you should be successful in making strong welds.

The definitions

Gas metal arc welding
GMAW, as identified by the American Welding Society, is also known as MIG (Metal Inert Gas) and uses a continuous solid wire electrode for filler metal and externally supplied gas ( usually from a high pressure cylinder) for shielding. The wire is usually mild steel, usually copper in color as it is galvanized with a thin layer of copper to protect it from rust, improve electrical conductivity, increase contact tip life, and generally improve the performance of the arch. The welder must be configured for positive DC polarity. The shielding gas, which is usually carbon dioxide or a mixture of carbon dioxide and argon, prevents the molten metal from reacting with the atmosphere. Shielding gas flows through the gun and cable assembly and exits through the gun nozzle along with the welding wire to shield and shield the molten weld pool. Molten metal is very reactive with oxygen, nitrogen and hydrogen in the atmosphere, if exposed to them. The inert gas usually continues to flow for some time after welding to continue to protect the metal as it cools. A light breeze can wash away the armor and cause porosity, which is why welding outdoors is generally avoided unless special windshields are installed.

However, if done correctly, operator appeal and weld appearance are excellent with MIG and it is the preferred process for most welders. Good technique will give excellent results. The properly finished weld has no slag and virtually no spatter. A “push” gun angle is normally used to improve gas coverage and achieve the best results. If the material you are welding is dirty, rusty, or painted, it should be cleaned by grinding until you see shiny bare metal. MIG welding can be used with all major commercial metals, including low carbon steel, low alloy steel, stainless steel, and aluminum, with potential for success for a novice.

MIG welding in aluminum
Welding aluminum requires more than just changing aluminum wire. First get comfortable welding steel. Since aluminum is very soft, it requires aluminum drive rollers that have a U-shaped groove and no teeth to bite or cause the wire to chip.

The cleanliness of the wire and the base metal is essential. Wipe the material with acetone on a clean shop rag. Use stainless steel wire brushes that have only been used on aluminum. The tension of the drive roller and the length of the gun should be minimized. A gun coating of Teflon, nylon or the like is required to minimize friction when feeding the wire and 100% pure Argon gas is required for the shielding. Special contact advice is often recommended. Special techniques of movement of firearms are often highly desirable. It's a challenge, but it can be done.

Self-shielded flux-cored arc welding
FCAW according to the American Welding Society, or flux-core for short, is different in that it uses a wire that contains materials in its core which, when burnt by the heat of the arc, produce shielding gases and flux agents to help produce sound. welding, without the need for external shielding gas. We do a solid weld, but in a very different way. We have internal shielding instead of external shielding. The shielding is very positive and can withstand a strong breeze. The arc is powerful, but has splash. When finished, the weld is covered with a slag which usually needs to be removed. A "drag" angle for the gun is specified, which improves operator visibility. The settings of the wire feeder welder are slightly more critical for this process. Poor technique will have amplified results. This type of welding is mainly performed on mild steel applications outdoors. The Innershield® .035 "NR-211-MP is often used for 115-volt machines and the .045" Innershield NR-211-MP is typically used in 230-volt machines. Farmers have found that these products can save a plantation or crop by fixing a broken machine in the middle of the field in record time. General rules of use

MIG
As a general rule, it is recommended that a compact 115-volt input (or 230-volt) MIG wire feeder welder be used indoors on new, clean 24 to 12-gauge steel. 12-gauge has a just under 1/8 "thick. 24 gauge is less than 1/16" thick. The smaller wire (0.025 ") will make it easier to weld the thinnest material (24 gauge). The 0.030" diameter wire will weld a somewhat faster deposition rate. If you need to weld material 1/8 "to ¼" thick with MIG, you will need the larger capacity compact machine which will require a 230 volt input. The higher amperage range of this machine can better handle your one-pass welding needs and you may not have to waste time with second or third passes. The 230 volt machine can also use 0.035 "diameter wire. To weld MIG welding materials over ¼" thick you need a larger capacity, truly industrial machine. If most of your welds are done indoors on clean material less than 1/8 "thick, a MIG machine running on 115 volts is probably your best bet for economic reasons as a machine with 230 volt input will be more expensive.

Flux fondant

The flux core process is only recommended on materials as thin as 20 gauge, a bit thicker than 24 gauge we said for MIG. In general, this process is best for welding thicker materials in one pass, especially if you need to weld outdoors, such as repairing a tractor in the field. A 115 volt flux core machine using an electrode such as .035 "Innershield NR-211-MP will generally allow you to weld steel up to ¼" thick. Note that this is more than double the maximum thickness of the 12 gauge with MIG on 115 volts. With the correct electrode on a suitable machine, such as .045 "Innershield NR-211MP, and a 230 volt input machine, you can weld steel up to 1/2" thick. Note that Innershield® NR-211-MP requires the machine to be configured for negative DC polarity.

Advantages and disadvantages
While both processes have pros and cons, we'll try to walk you through some of the more common ones.

MIG
Benefits:

The best choice when aesthetic appearance is an issue as it provides lower projection levels than cored flux. Arc is soft and less likely to burn through thin material
The lower spatter associated with MIG welding also means there is no slag to flake off and a faster cleaning time
MIG welding is the easiest type of welding to learn and is more forgiving if the operator is somewhat erratic in maintaining the length of the arc or providing constant travel speed. Procedural settings are more forgiving
If you are skilled and have specific guns, shielding gas, liners, drive rollers, and electrodes, MIG can weld a wider range of materials including thinner materials and different materials such as than stainless steel, nickel alloys or aluminum.

Disadvantages:

Since an external shielding gas cylinder is required, MIG welding may not be the process of choice if you are looking for something that offers portability and convenience. MIG also requires additional equipment such as a hose, regulator, solenoid (solenoid valve) in the wire feeder, and a flow meter
The welder's first job is to prepare the surface by removing paint, rust and any surface contamination.
MIG has a soft arc that will not weld thicker materials properly (10 gauge would be the maximum thickness MIG could weld solidly with the compact 115 volt wire feeder we're talking about or ¼ "with the compact wire feeder. input voltage of 230 volts.) As the thickness of the material (steel) increases, the risk of cold running-in also increases as the heat input necessary for proper fusion is simply not possible with these little machines

Flux fondant
Benefits:

Self-shielded electrodes are optimal for outdoor procedures since flux is built into the wire for positive shielding even in windy conditions. External shielding gas and additional equipment are not required, so setup is simpler, faster and easier
The cored process is most suitable for applications with thicker materials as it is less prone to cold lapping

Disadvantages:

It is not recommended for very fine materials (gauge less than 20)
When welding flux-cored, machine settings must be precise. A slight change in the position of a button can make a big difference in the arc. In addition, the position of the gun is more critical because it must be maintained consistently and at the proper angle to create a good weld.
This process creates spatter and slag that may need to be cleaned up for painting or finishing.

 
It should be noted that the same machine can be used to weld with both MIG and Flux Core processes, although a special package is usually required to switch between applications. Drive rollers, shielding gas, gun liners, contact tips, and procedure parameters should be considered when changing processes

Choose yarn

Another area that a novice welder can worry about is how to choose the best wire. The correct electrode diameter depends on the thickness of the plate and the welder you have. A smaller wire makes it easier to weld thinner plates.

For a 110 volt input MIG machine, an electrode such as the Lincoln .025 "SuperArc® L-56 is the smallest size available and the easiest to use on very thin material. A .030" SuperArc would weld material. slightly thicker a little faster. For cored flux, a 110V machine would run 0.035 "wire (like the Lincoln Innershield NR-211-MP) as this is the smallest size manufactured and that is all the machine can run. .

For a 230v MIG machine, most people weld heavier sheet metal and switch to the 0.030 "or even 0.035" diameter solid electrode such as .030 "or .035" SuperArc® L-56 as they deposit the metal. weld faster and they can weld heavier plates. For flux cored with the 230 volt input machine, most people would go to Lincoln's Innershield NR-211-MP 0.045 "in diameter for plate up to ½" thick.

Realize that these little machines are great at what they do, but they can't do everything. Electrodes for production welding, hardfacing to resist wear and most specialty electrodes will exceed the capacity of these machines. You need to be careful to match your machine's output voltage with the electrode voltage and the correct wire diameter and wire feed speeds to make sure you have a compatible system. Tips for All

• It is very important to have a good strong working connection. This means you need to thoroughly clean or grind the surface of the metal where the work clamp is attached and use a firmly attached work clamp so that electricity can easily pass through the workpiece and return to the welder. Paint and rust are insulators. Remove them. This is a very common mistake to overlook
• Put the welder on a separate circuit breaker that is properly fused as outlined in your operator's manual. This is not another strand of Christmas lights. You are melting steel at around 5000 degrees F. You cannot weld with inadequate input power. Do not even try
  A good fit is a big plus. Weld seams are laps, fillets, and ends. Avoid spaces as much as possible to minimize burn problems. This is particularly critical on thin sheets
• Keep gun cable as straight as possible for fluid wire feed. Don't bend it suddenly
• Make sure the contact tip is in good condition (not elongated or melted) and that it is tight on the diffuser
• Cut the wire at an angle to a point before starting to weld for better starts
• Use and maintain the correct electrode protrusion and proper welding procedures
• Relax and try to hold the gun as steady and smooth as possible
• Observe and follow all welding safety precautions specified in your operator's manual. Pay special attention to the potential for electric shock, arc rays which can burn skin and eyes, fire and explosion, and adequate ventilation. For details, see ANSI Z 49.1