Getting Familiar with Your Welder

You should get familiar with the feel of the gun and familiarize yourself with the effects of changing things like current and wire speed before you try any actual welding. You should start your practice using a common grade of carbon steel like A36, which is the most commonly used steel in manufacturing heavy equipment and readily available as scrap at most industrial equipment manufacturers.

Try to find a piece that is about the same thickness as the steel in your work project so that you can get a feel for penetration without blowing holes through the piece. You will also want some thinner and thicker practice pieces as well to experiment with current and wire feed settings.

Start with a piece that is about 3.0 mm thick so that you don't have to worry about blowing holes through the piece if you linger a little too long at first. Use a surface grinder to remove as much rust and paint from the practice piece as possible and then clean-up the hard to access corner seams using a Longevity cutting tool. Be sure to also clean up an area away from the welding area to attach the ground clamp.

Holding the Gun

Using two hands to keep the gun steady is possible when you are doing MIG welding. Although you can do MIG welding one handed if you want, it is best to use both hands to keep a constant space between the work and the tip. Use your free hand to either support the barrel of the welding gun or the wrist of the hand holding the gun. If possible place the work piece on a surface that will allow you to rest your arm on the surface as well. The more consistent everything is during the welding process the better the finished product will be both mechanically and aesthetically.

Setting up the Welder

Many welders will come with a chart attached to the welder cart that will give you a starting point for the current and wire speed based on the material and the thickness of the piece. If you don't have a chart you can start with both settings at 50 percent and adjust as necessary until you are comfortable with penetration depth and fill. You definitely want to orient the gun to ensure that you have a clear view of the flame and the welding pool as you weld. Set the gun up so that approximately 1/2" of wire is protruding past the shroud.

Starting the Weld

You should first tack weld the pieces together so they don't move while you are welding and you can use both hands then to keep the gun movement smooth and steady. The number of tacks you use should be determined by the length of the weld but one per foot of weld should be adequate. Once you are all set several things need to be done almost simultaneously to start the continuous weld. First position the welding gun where you want to start the weld. Then simultaneously pull the trigger and tilt your head forward so that the mask and eye protection fall into place. If you prefer you can hold the gun with one hand and use the other to manually position the face mask instead. It really depends only on the welder's personal preference.

Welder Movement

There are a variety of gun movements used in MIG welding. Generally some form of zig-zag or circular weaving motion is used to ensure the arc acts against and penetrates both pieces to be welded.


It's much easier to lay weld onto a sheet of steel than to weld two pieces together, so when you are first starting it's best to practice your technique that way. Once you have started the weld after a couple of seconds welding a liquid weld pool should develop. Once the pool develops you need to start moving the weld gun or you will start blowing holes through the work piece. If you move too fast you will get poor penetration and a weak weld so you should practice until you feel comfortable that you have proper penetration.

Welding Direction

Pushing the gun rather than pulling is a good habit to get into as it improves coverage of shielding gas over the weld area. But it has disadvantages as well because you have to move the gun over the pool and if you are not careful you'll spend a lot of time on gun and electrode maintenance. This is especially true if you are welding vertically. Use whatever technique you feel most comfortable with since there really isn't a right or a wrong way to do this.

Spend a little time laying welds on your sheet to get a feel for welding on different power settings before trying to join two pieces of metal. Practice laying welds on a single plate until the welds start looking neat. It should only take a couple of hours practice to get a feel for MIG welding and lay down a nice uniform bead.

Evaluating the Weld Bead

A good weld bead will be raised slightly above the work surface and look like a hump and not a mountain range. You should see a progression of equally spaced semi-circles with the hump pointing away from the direction of movement.