Welding thin metal for self-taught beginners is always difficult. The biggest problem is, of course, metal burn-through. Today we will make such an article a recommendation, what are the most common causes of burns, and how to avoid it.
Let's start with the electrodes. When there is a lot of experience in welding, then one millimeter metal can be welded with 3 mm electrodes. But if the experience is still not enough, then it is better to have and use electrodes of a suitable diameter for the required metal thickness.
It is better to purchase electrodes for a beginner with a rutile coating. These are the brands MR-3, ANO-21, MONOLIT. Or with a rutile cellulose coating, this is OK-46.
Such electrodes are unpretentious to the surface of the metal to be welded, and they can be easily welded with pull-off-spot welding.
It is better to clean the surface of the welded metal from dirt and rust with a brush or grinder. Otherwise, during welding, everything will foam and interfere with the normal formation of the seam.
Another very important point is where to connect the holder with the electrode, to the plus of the device or to the minus. According to theory, we were taught this way, when welding thin metal, we connect the grip to the plus, this is the reverse polarity.
But in practice, everything turns out not so, it is easier to weld without burn-through when the holder is connected to minus-straight polarity. I experimented for a long time and came to exactly this conclusion. But best of all, try to compare yourself, alternately switching the wires and draw your conclusion.
Setting the welding current is very important. There are tables with recommendations for selecting the current depending on the diameter of the electrode, but it is difficult for a beginner to choose the optimal mode. Most recently, the channel had an article on how to choose the required current without a table, read the article HERE.
Make a minimum gap between the welded edges of the metal, because the edge quickly burns out. For 1-2 mm metal, make the gaps no thicker than a needle!
There is one interesting way of welding thin metal, welding with electric rivets. Can be used when sheet metal is to be welded to the base. A welding point is made, which melts the upper metal and welds to the lower one. The connection is strong and easy. There is such an article on the channel, who is interested to look through.
Perhaps the most important reasons were voiced, it remains just to cook more and gain experience. Over time, doing the same thing will get better and better. Good luck, see you soon!