MIG, or metal inert gas welding, is a typical process of welding that new welders usually get used to first. You may not purchase a MIG welder yet, but you still need to properly understand how to use MIG welder before you start working with it.
A Step-by-step Guide on How To Use MIG Welder
Safety First
Before even doing any welding project, no matter how easy it seems, one must have the proper safety measures. You should wear all the suggested protective gears, and make sure to remove all potential fire hazards from the area.
Preparing Metal
The MIG wire cannot combat oil, dirt, rust, or contaminants as well as flux-cored or stick electrodes. This is because those things contain more special additives. Thus, you must prepare the metal properly before starting the work.
Use some metal grinder or brush to clean the bare metal before beginning to strike an arc. In addition, make sure that the work clamp is connected to clean metal.
Remember that any electrical impedance can affect the performance of wire feeding. To make sure thicker metals have strong welds, bevel the joint. This will make the weld capable of fully penetrating the base metal.
Preparing Equipment
Before arc striking, check the equipment and ensure all cable connections are tightly fitted to avoid fraying damage.
Then, select the correct polarity for electrode, as MIG welding will need DC electrodes to be positive/reverse polarity. You can usually find the polarity connections inside the machine.
Turn the shielding gas on, set its flow rate toward 20/25 square feet each hour. If you think the gas hose is leaking, apply some soapy solution of water and observe for bubbles. In the case of actual leaks, discard that hose.
Too little/too much tension placed on either of your drive rolls/wire spool hubs will make wire feeding unreliable. Follow the user manual and adjust.
Selecting Wire
There are two main types of wire for steel. There is the ER70S-3 AWS classification, which is great for doing all-purpose welding.
If you weld on rusty or dirty steel, you should use the Use ER70S-6.
Wire with the diameter of .030-inch is the best choice for motorsports as well as home applications. After all, it is applicable to many ranges of metal thickness.
For the thin materials, you should choose wires with .023-inch diameter, as it can help with reducing heat input.
Wire Stick-out
What is stick-out? It’s the extending unmelted electrode from the contact tube’s tip. Of course, this does not include the length of the arc.
Typically, you should maintain the stick-out at 3/8 inch. In addition, you should also listen to some sizzling bacon sound. If the sounds seem irregular, there is a high chance that the stick-out is too long.
Pushing or Pulling?
The pushing/forehand technique means that you will be pushing your gun away from/ahead of your weld puddle. This technique typically makes the arc force move further from the puddle. Thus, it results in lower penetration alongside flatter, wider bead.
The pulling/backhand technique means that you point the gun back at the puddle, dragging it further from the deposited material. This technique usually leads to deeper penetration along with a narrower bead.
When trying to MIG weld the mild steel, both the pull and push method are applicable. However, you should remember that pushing can give you a clearer view, enabling you to direct wire to the joint better.
Travel Angle
Place your gun in a perpendicular position, the angle it’s relating to is the travel angle. Normal conditions for welding requires the travel angle of between 5 and 15 degrees.
If you travel at more than 20 degrees angles, there can be more arc instability, less penetration, and more spatter.
Nothing Beats Practice
While all of this seems complicated at first, you can quickly familiarize with them through practice. After all, welding is something that requires quite a lot of patience.
I hope that you will be able to add more welding variations to your DIY projects after some time!