The article will be a good tip for self-taught welding. Subscribers were asked to show how to weld fillet welds with an electrode. These seams are some of the most difficult for a beginner.
Often there is such a picture after welding metal in an angular position. I'll show you a situation when you need to connect metal of different thicknesses. How to set the current and how thick the workpiece is (thin or thick). The correct position of the electrode when welding is so as not to burn through the thin and weld well the thick one. And other important little things.
I took two strips of metal of different thickness. One is 2 mm, the other is 8 mm. We will make a corner joint, leave the thick metal in a horizontal position, and weld the thin metal to it at a right angle - approximately, I did not expose it in a square, this is just an example.
We will select the welding current over a thick plate. We connect the holder with the electrode to the plus of the welding inverter. This is reverse polarity - plus to the electrode, minus to ground.
I will take the electrode with a rutile cellulose coating of OK-46 grade. Its diameter is 3 mm, although for such a thickness it is better than 4 mm, but I simply do not have such, I do not work as a four. And here's how easy it is to set the welding current in just 10 seconds.
Set the sufficient current for rutile-coated electrodes as follows. We light the electrode and slowly lead the angle towards ourselves. We are waiting for the seam width to be maximum. This fiery path behind the electrode will make its widest possible channel.
We abruptly interrupt the welding and measure the width of the fire channel-seam with the electrode itself. Above the still red seam, it is clearly visible through the mask, we estimate how many electrodes with coating will fit here. Sufficient current will be if 2.5 diameters of the electrode with coating fit.
That's it, this energy is enough. But there are monolith electrodes, they have a thick coating, then 2 diameters of electrodes will be enough. This will be the maximum current for a specific metal thickness, if desired, it can be slightly reduced, but not added in any way.
The sectional weld has such a mushroom shape. The maximum penetration depth in the metal is in the center and decreases along the edges. At the edges of the seam, the energy is much less, therefore, the penetration is smaller.
Welding process layout! I inserted the fungus into the round timber, the electrode burns, the arc melts to the maximum in the center of the electrode. The farther from the center, the less metal penetration is. As in the city-in the center the tallest buildings, and on the outskirts there are many low-private sector!
How to hold the electrode. If the thickness of the parts were the same, then the electrode would be held in the middle between these planes. And in our case, we direct the axis of the electrode into a thicker metal, the penetration is more needed there.
A small amount of energy is sufficient for thin metal. We catch it when welding with the edge of the weld. Wet it a little with the edge of the fiery channel behind the electrode. Cook backward. We tilt the electrode towards ourselves and also pull towards ourselves. We make very small oscillatory movements with the tip of the electrode - this way we mix the weld pool and the seam will be better.
You need to light the electrode on toast metal away from the thin one, 10-15 millimeters. We form a weld pool, when the pool spreads normally, you can direct it to the corner of the joint. We hold the main part of the bath on thick metal, and slightly moisten the thin one. This is how we cook.
The photo shows that I was in a hurry at first, did not fully warm up the bath and sent the bath to the corner itself early, so there was a lack of penetration for several millimeters. I didn't fix it, with this joint I got a good visual example of how not to do it!
Then everything went well. Thin and thick metal was completely welded, there were no burn-throughs on the thin one. Thick with good penetration.
I will do welding of a corner joint with metal of the same thickness in the near future and will share all the intricacies with subscribers. There are little things and tricks. Goodbye everyone, Happy New Year!