How To Use a Mig Welder Properly
MIG Welders (Metal Inert Gas) welding equipment was developed back in the 40s and the basic functionality and construction of this equipment still remain same. This tool includes use of an arc of electricity for the creation of short circuit between the continuously fed wire and metal.
Short circuit with the use of a shielding gas melts metal and joins them together. After removal of heat, the metal is allowed to cool down and it solidifies to give you a new form of metal.
This process of welding works well with a variety of different metals including stainless steel, copper, nickel, aluminum, magnesium, carbon steel and others.
Before jumping on the discussion of how to setup this equipment for proper use, you need to have a complete idea of what are the main parts of a MIG welder.
Parts of a MIG Welder
Welder: When you open up a welder, you will find MIG wire spool and a number of rollers responsible for pushing wire to the torch. This spool of MIG wire is held with the aid of a tension nut that should remain tighten in order to prevent from over-running after the release of the trigger.
Shielding Gas Supply: A shielding gas cylinder is placed behind the MIG. This gas is responsible for shielding the weld and without this gas; weld will be splattered and improper. Before using this equipment you should open up cylinder valve to check if there is gas inside it.
Welding Torch: The torch includes a trigger that controls the feed of wire and electricity flow. A replaceable copper tip is guided by the wire and size of this tip varies with different MIG Welders and diameter of wires used.
Earth Clamp: This part completes the entire circuit that flows through welder, welding torch and the metal. The clamp is either clipped to the metal piece or will be enclosed with a metal welding table. This part must be free from any rust or dirt that may be hindering its connection with the metal to be welded.
How to Use A MIG Welder:
You should properly set up welder and the metal piece to be welded.
- Make sure that the shielding gas valve is open and the setting is around 14 LPM.
- Then turn the welder on.
- Earth clamp must be clipped to metal or to welding table.
- Set power and wire feeding speed at the right setting for the proper combination of both for welding.
- Clean metal and all the edges that would be joined must be grinded well.
- Now squeeze the trigger and touch it to the welding piece.
Now that the welder and metal piece is properly set, you need to start the welding process. For beginners in welding, before welding on the actual pieces to be welded you should practice few times on scrap pieces in order to get familiar with the process and to identify correct level of speed and power settings.
Welders vary in settings and thus you need to check yourself which MIG welder is appropriate for you. Too little power can give you splattered welding and weld may not even get through metal piece however too much power can completely melt the metal to be welded.
Right settings would be one where you get smooth and nice welds. Quality of weld would make you realize if you have right setting or not.
Follow these simple steps for welding process:
- Welding machine polarity must be set to DCEP.
- During the process of welding, electrode length must be kept constant extending anywhere between 1/4 to 3/8 inches distance from contact tube. With this consistency, you will be able to make consistent welds.
- Welding can be performed for a joint either with a technique called drag or push. Drag welding involves pulling of beat along contact tip. A narrower bead can be obtained with enhanced diffusion. On the other hand push welding involves pushing of beat with contact tip. You can obtain wider bead with the technique. For either technique, angle should not be more than 10 degrees. Wire must be kept at the weld pool front point.
- Varied Welds:
- For making flat welds, you should use your MIG welder for placing metal into the joint directly. A back and forth movement should be made in order to fill all large spaces. The gun should be held at 90 degrees.
- For making the horizontal weld, gun angle must be slightly lowered that prevents from sagging. Angle (push or pull) should remain normal along with back and forth movement for filling up of gaps. Only the wire diameter must be slightly small so that weld pool may not become too big.
- For vertical weld, begin from the top and move downwards along gravity. This gives you prevention from material penetration through arc. For metals that are thicker, you should begin from the base and go all the way upwards. You may need to lower down power up to 10-15% in order to deal with gravity.
- For overhead weld, the process remains same as for standard welding process however only you need to increase traveling speed along with gas flow rate. This process will reduce risk of filler falling from joint. This process gives quicker spatter build up and thus you would need to keep welder nozzle clean.
When the welding process is completed, you would need to grind off excess filler. In case of any defects, you would need to grind down and repeat the welding process.
Safety Precautions to be considered before use!
Safety of yourself along with the equipment is a vital issue. Thus you are recommended to strictly follow all the safety precautions for using MIG Welder. You should be prepared to keep yourself protected from all the harmful light and extensive heat that this equipment deals with.
Welding Helmet: It is extremely important to wear a welding helmet. Because extreme harmful light is generated during process of welding and you need to keep your eyes protected. If possible use a welding screen and make a protective border around yourself to keep others safe from this light too.
Gloves and Leathers: Be protected from the metal that melts and splatter during the welding process. For that purpose, you should wear gloves at all times during the process so you can have more control and can keep yourself protected. The leather is best to keep your skin save from heat. If not leather, make sure you wear cotton and not plastics. For a welding process that would take more than 2-3 minutes, you must be covered up as UV lights burn quick.
Leather boots: Wear leather shoes as when metal melts it usually falls down and you may get yourself or top of shoes burned.
Welding Area should be ventilated well: Dangerous flames are produced as you weld metal. The area for welding should be well-ventilated in order to make you breathe well. For extended welding process, it is best to wear a mask or respirator in order to avoid breathing hazardous fumes.
It is important to learn proper methodology for using any tool . By following this guide you will be able to get your work done with convenience and ease without risking your own safety with safe use of your MIG welder.
Keep working and with practice you will be able to get hold of this equipment even better. For perfection it is best to spend time and work on scrap pieces of metal so that you do not waste your actual metal pieces that need to be welded.