MIG wire comes in a wide variety of materials and diameters. Also known as an electrode, the wire you choose must be right for the job in order to ensure the strongest, tidiest weld you can produce.
Here are the key features of MIG wire. Keep them in mind as you shop for the brand and material that will make you the best welder you can be.
1. Metal Soundness: High-quality MIG welding electrode must be characterized by excellent fusion and a lack of porosity. Poorly made wire or that made from inferior materials is far more likely to cause carbon monoxide bubbles in the weld (porosity), decreasing strength as well as potentially marring the appearance.
2. Wire containing quality deoxidizers: A deoxidizer is an element that will combine with oxygen more readily than carbon so that harmless slag is formed instead of CO. The best deoxidizers are aluminum, zirconium and titanium, although silicon and manganese remain the most common deoxidizers in today’s wire options.
3. Puddle fluidity: The weld puddle needs to be fluid enough to create smooth edges in the bead shape but not so fluid that it causes control issues. This can be especially vital on fillet or multi-pass welds where fusion is essential. A smoother bead shape will reduce the need for post-weld grinding where appearance is important.
How to Choose Mig Welding Wire
With these features in mind, here are tips for choosing the right wire for your job.
Tip #1: Familiarize yourself with the wire types available.
Knowing what materials are available will help you select the right one for your task. A brief overview of types includes aluminum, bronze alloy, carbon steel, copper alloy, hard facing, low alloy steel, magnesium, maintenance alloy, nickel alloy and stainless steel. Each has unique weld characteristics and they contain varying amounts of deoxidizer.
Tip #2: Select wire with the proper amount of deoxidizer.
Manganese and silicon are the most common deoxidizers and you’ll need to select a wire with the correct levels for the welding jobs you have. The more deoxidizer, the greater the fluidity tends to be. Adding titanium, zirconium or aluminum to the electrode tends to lower fluidity and creates a puddle that is better for applications such as welding pipe where the molten metal is likely to run off the job if too fluid.
Tip #3: Choose wire compatible with the metals you are welding.
It is always best to use wire made of the same material as the metal you are welding for greatest fusion. For carbon steel your options include solid wire or flux-cored wire depending upon your preference and the availability of shielding gas.
Tip #4: Use a MIG wire diameter rated for the amps required on the weld.
For example, .023” wire is suitable for use between 30 and 90 amps, .030” wire works well between 40 and 150 amps, and .035” wire is right for amp settings between 55 and 180 amps. Larger diameter .045” wire can be used on jobs that require up to about 260 amps. Most wire packaging will offer a chart that shows acceptable use for the diameter of the wire contained.
Tip #5: Use your welder’s set up chart to determine wire diameter
Most welders from Hobart, ESAB, Miller, Lincoln and other leading brands come equipped with a set-up chart that spells out clearly what diameter wire should be used, given the amps required.
Tip #6: For all-purpose DIY welding on aluminum use medium to large diameter wire.
Most welder manufacturers suggest that if you want one wire that will work well on the widest variety of tasks that you select either .030” or .035” aluminum wire. You’ll enjoy good weld puddle control and a solid, durable weld for most tasks.
Once you get comfortable with your welder and the wire choices available you’ll find it easy to match the right wire with each task. Your welds will show quality and will prove themselves in the long-run with greater durability and strength. Follow these guidelines and you’ll soon know how to choose the right MIG wire for the job.