Last Updated on October 4, 2020
Does Metal Inert Gas or MIG welding sound familiar to you? Read this guide and you will understand all it takes to MIG-weld like a professional in a short time. It took me several practices to get it right and I am sure you will succeed too.
What is MIG Welding?
MIG welding, also referred to as Gas Metal Arc welding is a combination of the metal with inert gas welding. It is a welding process in which an electric arc forms in the middle of the consumable MIG wire electrode and the metal work-piece. It is the consumable wire that heats the metal work-piece forcing them to melt and join at the edges.
Benefits of MIG Welding
MIG welding dates back to the 1940’s era, and the general principle behind it remains the same. It makes use of arc electricity to create a short circuit in the inert gas to melt metals. The metals will cool and form a newly infused piece of metal once the heat is withdrawn and the metal cools.
One of the main benefits of this welding type is that it can practically weld most types of metals. These include steel, aluminum, copper, magnesium, bronze, silicone, and alloys. It can join different thicknesses of metals and provides all-position welding capabilities.
How the MIG Welding Machine Works
The MIG welding machine comprises of several components, these are; the welder, gas tank, welding gun, and ground clamp. The welder contains the spool of wire plus several rollers that push the wire out to the welding gun.
The Gas tank is located behind the MIG. The tank comprises of Argon gas or a mixture of Argon and CO2. It is this gas that will shield the weld as it is forming.
The welding gun does most of the work for you. It has a trigger controlling the wire feed alongside electricity flow. In most cases, the gun will be pre-set before using it.
The ground clamp completes the electrical circuit between the welder, welding gun and your welding project. This clamp is clipped to the metal that is being welded and its clip must make very good contact with the piece of material being welded to make it work.
Safety is Paramount
Your safety is very important when it comes to MIG welding. The auto-darkening welding mask is a must, to protect you from the bright light. You will also need leather gloves to protect your hand from heat and molten metal splashing around. You must wear leather boots or shoes and cover them with non-flammable materials.
It is important to weld in a well-ventilated area because of the toxic fumes generated hence you should wear a respirator or mask.
Steps to a Successful MIG Welding
Step 1: Prepare for Your Welding
You need to ensure that the valve of the shielding gas is opened and the ground clamp is attached to the welding table or piece of metal directly. Make sure you have the proper wire speed plus the proper power setting adjustments.
The next step is to make sure your metal is clean if you want a strong and clean weld. Make sure you use the angle grinder to level the edges of the metal before welding.
Step 2: Lay the Bead
Once you have prepared your metal and welder, you should consider practicing by running a bead before welding two metals together. This step is most important for beginner welders. You can do this by using a piece of metal scrap and then make a weld in a straight line on the surface. Repeat this several times and adjust the power settings and wire-speed until you achieve a consistent result.
Keep in mind that using too little power may create a splattered weld that may not penetrate through the work. Applying too much power will melt through the metal completely.
You will probably know you are using the right power setting when your weld begins to appear smooth and when you hear continuous sparking.
Step 3: MIG-weld the Metals Together
Once you have tested your welding skill successfully on the metal scrap, it is time to complete the actual weld. Make sure you ground down the surface edges of the metal first, before making the sewing or welding motion across the top of the metal seem.
I do recommend that you weld from the bottom of the stock right to the top while pushing the weld forward with the aid of the tip of the gun. Once you have complete welding along with a position, you may be left with a big bump that you can handle by simply flattening it or apply a filler. You may need extra welding power to fill in the bumps and ensure it is properly joined.
Step 4: Grind Down the Weld
You don’t have to apply this step if you don’t care how the weld appears. You should consider grinding down your weld to smoothen it out if you are concerned about the final appearance of the material.
To achieve this, simply slap a grinding wheel unto an angle-grinder before you start grinding the wheel. The smoother your weld is, the less the grinding you will have to do.
Grinding can take a while and it can be very short, depending on how much welding you have done originally. You may want to take some breaks while grinding to stay hydrated. You should also consider wearing a full-face mask or respirator plus ear protection since the grinding room can heat up very quickly.
Keep your grinding materials appropriately once you are done and do not forget to practice as a beginner before you handle major welding works.
MIG Welding Pros and Cons
- It is the simplest form or type of welding.
- Thinner metallic materials can be welded easily.
- The operational cost for MIG welding is much lower than the rest.
- They can leave some deposits if you don’t choose the proper power and weld settings.
- Heavy smoke is release; hence you need to cover your face.
- It does not weld dirty metals.
With the information I have provided above, you can see how welding can be fun, and simple. Perhaps you may be faced with some challenges along the way.
Not enough shielding gas available from the welding gun is one of the major problems you may encounter when welding. Make sure you increase the pressure of the gas to resolve gas shortage issues.
Another problem you may encounter is the lack of penetration of the weld. If your weld is weak, you wouldn’t be able to join the metals together. This problem is due to a lack of power. Make sure you choose the right power of welding when practicing. Maintaining a constant weld is achievable if you choose the right wire speed and power.