Tag Archives: welding processes
So start to learn how to weld there are several questions that need to be addressed. To begin we need to determine what metals or alloys we intend to weld and then we are to choose the process and welding machine to use with that process. here we offer a brief description of the main welding processes and the welding equipment we will need.
For the welding of mild steel, stainless steel and aluminum we can choose from three main processes. Arc welding, MIG welding and TIG welding.
Arc welding uses welding rods or welding electrodes as a means of joining metals. This is the most simple and most likely cheapest way to learn how to weld. Arc welding machines are readily available either new or second hand and are most suited for welding mild steel and stainless steel in thicknesses of 1/8th inch and upwards.
Mig welding and MIG welding machines would have to be the most versatile and easiest of the how to weld procedures to master. No need to change electrodes as the machine operates with a wire feed system and employs a spool of welding wire within the machine. Great for welding both sheet metals and heavier steels. Can be used for welding mild steel, stainless steel and aluminum. Great for welding thin metal like on motor vehicle body-work.
Mig welders generally use shielding gasses s part of the process that can be limiting in outdoor welding applications, however there are gasless welding wires on the market suitable for welding mild steel. Having a small portable mig welding machine that uses gas free welding wire is a most versatile welding machine.
Tig welding is a high tech approach to welding. This process takes time to master but will provide the best quality weld for small intricate jobs. Can be used with stainless steel, mild steel and aluminum welding. Tig welding can also be used for many exotic and specialized metals such as gold.
Tig welder machines can be small and compact such as the ‘caddy’ welders that are also capable of stick or arc welding. These machines are often seen on work sites and used by maintenance crews. A most versatile welding machine.
Learning how to Mig weld is probably the easiest of all the welding processes. There are basic fundamentals to understand but once mastered you will be able to weld most metals in various positions with a mig.
The act of welding is simply fusing two metals together with the aid of a filler material. You first need to get enough heat into the metal to begin the fusion process. For this the power of the welder needs to complement the job to be done. For example it will be difficult to bring 1 inch steel to any sort of melting point with a 120 Amp welder.The more power in the mig welding machine the thicker the metal you can weld.
Filler materials or welding wire in the case of MIG welders will need to be the same as the work to be welded, e.g. welding aluminium requires aluminium welding wire. Also the wire gauge should also complement the work to be welded. For light welding of sheet metals you would use a .08 mm wire gauge. For thicker metals you will use 1.2 mm wires.
The basic set up with a mig is that the welding wire is fed through the welding cable to the welding gun; pull the trigger of the gun and the wire feed pushes wire to the job. The power level and wire speed must be consistent with the job to be done. Getting the two synchronised can be a challenge when you are learning how to mig weld. Once the combination is right the welding will be smooth and relatively quiet without splattering.
The power of the welder in relation to the work is most important, especially when the job being done could be a safety issue if the welded joint is not fused properly. A poor weld is often referred to as a cold weld or cold lap. A weld such as this can look perfectly fine but have no strength at all due to lack of penetration.
To prevent poor weld penetration the power of the welder must be sufficient to melt the parent work and fuse the metals together. Always weld with as much power as you can to ensure correct fusion of the joints.
How to mig weld with Gasless wire.
Mig welders will generally require a shielding gas however gasless wires are commonly available. Gasless wire is excellent for the welding of galvanized iron. Gas-less wire is also convenient where portability is needed or for site work when wind and breeze can blow away the shielding gas from the work.