Welding – Joining two metals together by melting the base metals while adding filler materials, can be both rewarding and fun.
Most Welders make a good living since welding is utilized in a lot of different applications in today’s world.
With advancement in welding technology, welding can now be carried out in any environment including under water.
Understanding the basics is significant. Once you understand the basics of how two metals are joined together in one arc welding process, learning the other methods will be easier.
Most importantly one needs to know the three basic types of welding before learning other things such as technique and machine settings.
Even welders experienced in one method will often need some training when it comes to welding using methods they are not experienced in.
One such area of confusion is often whether one should push or pull the arc when wire welding.
A simple answer to this question is whenever the welding process produces slag, always pull the arc. And since flux core welding produces slag the arc should be pulled along as opposed to being pushed.
It should be noted that the pulling technique is also called dragging.
The Different Types of Welding
While typically not explained in these terms, the different methods either produce slag or they don’t.
The Production of slag depends on how the gas is produced that protects the molten weld puddle from the atmosphere.
A lesser know fact about welding is that gases in the air we breath are not good for the weld’s overall strength and should be shielded from the molten puddle.
Most people are familiar with electrode welding. That is welding using the metal rods that are about a foot in length and covered with a hard substance called flux. This is also known as stick welding.
It is the easiest and cheapest form of welding.
The flux on the outside of an electrode produces the shielding gas when melted. This gas protects the weld from atmospheric impurities.
It does so by producing non-harmful gases immediately on top of the weld puddle which pushes the harmful atmospheric gasses away.
The hard flux also leaves a residue that covers the weld bead when the molten puddle cools and hardens. This residue is called slag.
Flux core welding also uses a solid flux. But instead of being on the outside, like on an electrode, the flux is contained inside the hollow flux core wire.
Just like with an electrode the flux inside flux core wire burns and produces a gas that shields the puddle from the atmosphere. Consequently, it also produces slag.
Supplied Gas for Shielding Against Impurities
Wire welding with solid wire requires the shielding gas to be blown down on top of the molten puddle from an external source.
This is called MIG welding which stands for Metal Inert Gas Welding.
There will always be an external bottle or tank of gas attached to the MIG welding cart to accommodate the need for shielding gas.
The supplied gas is fed down the welding lead and again, is expelled directly on top of the weld during the welding process.
TIG or Tungsten Inert Gas Welding also uses shielding gas from a bottle. Both MIG and TIG welding are performed best with the push method.
That is, the angle of the tip of the wire or tungsten rod is pointed slightly in the direction the weld is to go.
Basic Welding Tips
Cleaning your weld
The quality of all welds will be improved by simply cleaning the base metals as completely as possible.
Only electrode welding, in some circumstances, can be performed with base metals that are not completely free of rust and residue.
Reverse Polarity when switching from MIG to Flux Core.
Be sure to switch the polarity of the current when switching back and forth between MIG and Flux Core welding.
Depending on the machine, this may need to be done by switching the lead cables where they attach to the machine.
There you have it! If it produces slag, you must drag!