Greetings to all lovers of working with metal, all self-taught beginners in manual arc welding.
If you do not know a few simple rules on how to make welding tacks, then you can simply ruin the welding part. And you have to cut and weld everything again, and then again and again! Well, humor enough, let's start a serious conversation.
Before welding two or more parts, we need to rigidly fix them relative to each other. For this, welding tacks are made. In simple words, these are welding spots or short seams with which we will fasten these parts.
Tacking must be done with a current that will be greater than the current at which the main welding takes place. Then the depth of penetration of the tack will be sufficient and the part will be firmly fixed, during further welding it will not tear it off and there will be no displacement.
It is advisable to make the potholder not greasy, let its width be smaller than the width of the main weld seam, otherwise there will be a bump on the seam in this place. We need to fuse this potholder with the main seam and this place should not stand out later.
Before the main welding, you always need to beat it off from the slag, otherwise fusion with a tack will take longer and a bump may also turn out in this place, always beat off the slag.
Never start welding from the place of the tack. Otherwise, the welding arc will heat up this tack to a liquid state and its meaning of rigid bonding will simply disappear. In this case, the part may shift slightly, remember this.
It is advisable not to put a tack at the intersection of the welding seams of the part that you will weld, this is certainly not such a strict rule, but it is better to follow it.
Friends, and this is the most important rule that I wanted to tell you about. The welding tack and the weld seam itself decrease greatly in volume during cooling. This can be seen in the analogy with the snowball. We take snow in our hands, it has a certain volume, and then we make a snowball out of it, it will be a little smaller, also with a welding tack. you need to know this rule in order to grab parts at a right angle.
To understand how to use this rule, let's watch a detailed video that I made so that everything is clear with simple examples.