Step 15: Wire Feed Welders
As said before, much of what applies to stick welding practices also applies to welding with a wire feed unit. A steady hand, the correct angle of the electrode holder (stinger or gun), the correct heat setting, the correct travel speed, etc. are all necessary in both processes.
MIG capable welders are more costly than flux core welders because they include a gauge for regulating the shielding gas flow, a tube around the gun liner for carrying the gas to the gun, and a solenoid valve to start and stop the gas flow when the arc begins and stops. There is also the cost of the gas and a steel bottle to contain it. MIG welders can be used with flux core wire, but flux core welders cannot be outfitted as MIG welders. The advantage of MIG welders is that the welds have a better appearance and better penetration. There is also less cleanup after welding. But, in windy conditions the gas that shields MIG welds can be blown away before it does its job. MIG welding requires very clean steel while flux core welders can dig through some surface impurities to make a good weld. Flux core welders can be used in windy conditions with no problems.
In stick welding attention is given to the length of the arc. With wire feed welding the amount of wire sticking out of the end of the copper welding tip at the end of the welding gun becomes important. See the manual for your welder.
Wire feed welders are much easier to use than stick welders. They do not require the same skill level and amount of practice as stick welding. Some say laying a bead with a wire feed welder is like putting down a bead of toothpaste on a countertop. Almost anyone can do that. But, it is much more difficult to see where you are welding with a wire feed welder. It is not uncommon to wander off of the joint while welding with a wire feed welder. See the next step for three solutions.
Turn on your wire feed welder and let it run for a minute or so before beginning to weld.
In order to be sure your weld has good penetration and is not a "cold weld" (weld material laid over the parent metal without any real bonding), look for blue discolorations in the parent metal on both the left and right sides of the weld as a sign of good penetration.
When it is time to stop welding with a stick welder, the weldor simply pulls the electrode away from the steel and the arc stops. Those who are used to stick welders need to learn to release the trigger on the gun before pulling the gun up and away from the steel. Failure to do this results in a couple of inches of wasted electrode wire sticking out of the gun. This must be trimmed before beginning to weld again.
With my flux core welder I can sometimes begin a new weld without trimming the burned end, but there are other times when an arc will not begin without first trimming the wire to make a fresh new end.
There are some good videos on YouTube for how to do MIG welding.
(The photo is from Bing Images.)