Welcome to our channel for all self-taught beginners in welding and locksmiths. In order for a beginner to start more or less weld their first metal structures, you need to understand and see where the liquid metal stretches behind the tip of the electrode, and where the slag floats there.
If you do not distinguish in a boiling seething weld pool where there is metal and where there is slag, then the seams will turn out to be bad and fragile, as in the photo above. There will be continuous lack of penetration and constant slagging. So let's start practicing this simple way.
Let's start with theory. When the welding arc heats up the metal to melting, a weld pool is formed. This is a molten lake in which the metal from the electrode is mixed with the metal of the workpiece being welded. Plus, slag enters this bath - the coating of the electrode melts when the arc burns. And this whole cocktail is bubbling.
The slag is on the surface of the molten metal, covers it like a blanket and protects the liquid metal from oxidation by atmospheric oxygen.
We need to train our eyes to distinguish metal from slag in this boiling pot. The slag will be seen as a moving wave on the surface, just like a wave on the sea. Where the boundary of this moving wave from the smooth surface of the molten metal will be, this will be the boundary of the slag and the metal. We will try to catch the border with our eyes on this wave. Method one.
Take a piece of thick metal, 5 millimeters or more. If it is dirty and rusty, then we go over the surface with a grinder. And now, on a pure metal, we light the electrode and simply lead it and see what happens under the burning tip of the electrode.
We look from the side, place the part at eye level - put it higher or bend down ourselves, the main thing is to see from the side how this process is happening under the electrode. This is where we should see everything. Like slag, it travels in a moving wave on the surface of a lake of molten metal. We see, remember this difference, so that we can look at the electrode from a normal angle, as we should from above, and see this difference.
Method two.
We beat off the electrode from the coating, but we beat it off in sections. On the electrode we leave, for example, 5 cm of an area with coating, then a clean metal rod goes 5 cm. And the whole electrode is like this, we alternate. But let the beginning of the electrode remain without coating.
We light the electrode. The part without coating will often stick, but we try to keep the arc longer. We look at how a seam without slag is formed. And at the moment when the part with the coating starts to burn, slag will immediately pour into the weld pool, you will immediately see it. And so we will train to see the coming of the slag into the bath! Here we will also visually learn this difference, and we will see it all very quickly. Just a few electrodes are enough.
Method three.
We put our inverter closer to the place of training welding on a thick piece of iron. So that you can freely turn the current regulator with one hand during the welding itself.
That is, we lead the electrode with one hand, and with the other at this time we will change the value of the welding current.
We start with a lower current, the main thing is that the electrode burns stably, does not stick. Then we also calmly lead the electrode and gradually add current.
At this moment, the glow of the weld pool becomes stronger, because the slag wave moves further and further, the surface area of the metal without slag increases.
And so we play with the strength of the current, we watch how the slag envelops the surface of the molten lake of metal more strongly, then moves away from the tip of the electrode, clearing away the pure molten metal. And in these moments we will clearly see the movable boundary of slag and metal.
Spend one day off in the garage, alternating these 3 ways. At such simple and most visual moments of welding, an understanding of the difference between slag and metal will come quickly.