So, you’ve decided to take up flux core welding. It’s not a bad choice, especially for those just starting out. The equipment is pretty user-friendly, and you can strike an arc with the pull of a trigger. It’s a lot easier than starting to learn stick, for example.
While flux core is a more unorthodox way of learning to weld (stick welding is usually learned first), you can learn a great deal about the principles of welding. Nevertheless, there will still be a little bit of a learning curve. Here are some tips to help you get started.
Our 7 Tips & Tricks for Beginner Flux Core Welding
1. Make Sure Your Polarity Is Correct
When welding dual shield flux core (flux-cored wire with shielding gas), most wires are DC+, which is direct current electrode positive. This means that 2/3 of the heat in the arc will be directed toward the wire.
However, some wires, especially those that are self-shielded, are intended to be used with DC- which means direct current electrode negative. If you weld them with DC+, you will produce considerable spatter since the wire can’t take that amount of heat. You also won’t get as much penetration into the joint.
2. Learn To Drag the Welding Gun
The preferred travel angle for FCAW is a slight drag. Since there is flux and slag that results, you have to drag to prevent the slag from going underneath the weld. But you also don’t want to drag too much.
Anywhere between 15°–30° is an okay angle to drag the gun. Any more than that and the throat of your weld (the distance from the joint to the surface of the weld) will start to be too convex. Unless otherwise specified, you want a generally flat weld appearance. The temptation to push comes in because this creates a flatter weld appearance. But this not only creates opportunities to trap slag, but the weld can also be too concave; that is why a slight drag is preferred.
3. Watch Your Travel Speed
If you are trying to achieve a smaller size weld, don’t just move the gun faster. There are other variables you need to consider. Try turning your wire speed down first. Then you can move at more or less the same pace. If you move too quickly, you might not let the weld fill in enough.