Greetings to the channel for self-taught garage and suburban self-taught in manual arc welding. The easiest welding for a beginner is welding with a tear-off electrode. This is how a thin profile pipe is welded in their area.
But here, too, there are several tricks, applying which, you can get very dense welds - flake to flake, and they will be quite beautiful in appearance.
I will show this method on a profile pipe 40 by 60 mm, 2 mm thick. I made slots in a pipe with a grinder about 2 mm wide, this will imitate pipe joints with a gap. First, let's see the desired welding result, and then we will analyze in detail what and how to do.
Here is an enlarged photo of a seam made with a tear-off electrode. The scales are quite dense, as welders say, scale to scale. Such a seam can also be used for welding a structure under water - so that it is airtight, it does not flow. Now let's move on to a set of recommendations for a beginner for such a welding.
For frequent pull-off welding, you will need rutile or rutile cellulose coated electrodes. Such electrodes are easily re-ignited, boiling point by point.
These are the ANO-21 electrode brands. MP-3. OK-46 00. MONOLITH. ARSENAL.
To make it more convenient to often interrupt and restart welding, it is better to clamp the electrode in the holder in a position of 90 degrees. For very beginners, you can even divide the whole electrode into 2 parts with a grinder, a short electrode is simply easier to control.
If we cook a thin profile pipe up to 3 mm, then it is better to put the inverter cables in the position of straight polarity. This means we connect the holder with the electrode to the minus terminal of the device, and the mass to the plus terminal. This will reduce the likelihood of burns.
We will set the welding current approximately like this - experimentally we will find the golden mean when the electrode does not stick and does not burns through the pipe wall for at least a couple of seconds of continuous arc burning - on the pipe metal without a gap, it will burn through the gap faster.
I have a 3 mm electrode of the ANO-21 brand, the welding current is set at a value from 80 to 90 amperes.
And now the very movements of the electrode.
We ignite the electrode at the beginning of the gap. We set fire to and tear off several times, a couple or three times. We do this so that the first point turns out to be the desired width, approximately 2-2.5 diameters of the electrode with coating are needed. This will be the desired optimal width of the future seam. And here the very essence begins.
Re-ignition. The end of the electrode is lowered into the boundary contour of the previous weld pool. We can say we will go a millimeter inside the contour of the previous weld pool.
And at this moment we are carefully watching so that under the electrode the weld pool spreads out with a thickness similar to the thickness of the first welding spot. How this width turned out, at this moment we make a detachment of the electrode.
And so we do point by point, we look to get the same width of the weld pool spread as the previous point.
It is also important how and in which direction to detach the electrode, see.
We detach the electrode a little back and to the right. So we additionally push the slag back a little in the weld pool above the metal. It's just that the repeated point of the metal will spread better.
This should be tried to compare in practice. I prefer to pull off in the lower position in this way, the seam flakes are smaller with this method. That's all the theoretical preparation, let's cook some more, let's see what happens.
Cook point by point. We are not in a hurry, if there are signs of a close burn-through - the weld pool starts to be concave, then we increase the time between repeated ignition. We welded a seam, let's see.
The slag begins to move away in one continuous crust, which means the seam is smooth and with small scales.
Indeed, with multiple zooming in, everything turned out well. Pretty cute and tight.
Friends, all the little things in the article cannot be conveyed, only the main things. To whom this topic is important, I will upload a video with this process and a detailed story to the channel tomorrow, September 2. Come in and see.