When you weld 2 parts, the most important thing is not the selection of the current and the diameter of the electrodes, cleaning the surface and setting the required gaps. The basis of the basics is to learn to see through the mask the difference between metal and slag. Everything else is important, but without understanding this difference, it is meaningless.
Everyone who began to weld glands with an electrode went through this stage. You strike the electrode, the arc lights up. It seems that you lead the electrode along the edges of the parts to be welded, behind the tip of the electrode everything boils and foams.
Then he beat off the slag with a hammer, and there is no continuous weld seam. The metal stuck to one piece of iron, then to another. Sometimes there are small areas that hold both pieces of iron together, but there are not many such areas! It's just that we still cannot distinguish between metal and slag in this fiery plume, which stretches behind the electrode. What should we see at all?
Here we have two edges that we must weld with an electrode. When we lit the electrode, a pool of molten metal formed between these edges. This lake should wash, wet both edges of the metal at the same time.
But on the surface of the lake of fire there will always be seething slag. It covers this lake, but not completely. There is a small gap between the tip of the electrode and the edge of this bubbling slag. It is in this gap that we see the molten metal of the weld pool itself.
The slag goes behind the tip of the electrode, as it were, as a moving, moving wave, which completely covers the molten weld metal.
Our task is to learn to see this gap between the end of the burning electrode and the slag wave, which is a strip and is very mobile. That is, we see the metal of the weld pool itself in the gap and it is with this metal that we need to wet both edges of the welded glands.
When it turns out to clearly and consciously wet the edges with liquid metal (both edges at the same time) along the entire length welding seam, then after cooling and removing the slag with a hammer, we will have a normal seam, which held the two pieces of iron together in one!