Choosing a welding machine is easier when you start from the work, not the machine. The three processes you will see on most shipyard and fabrication floors are MIG, TIG and Stick (arc). Each one has clear strengths.
MIG welding (GMAW): speed and productivity
MIG feeds a continuous wire through the torch while a shielding gas protects the weld pool. It is fast, easy to learn and well suited to carbon steel from thin sheet up to heavy plate.
- Best for: production welding, structural steel, long seams.
- Watch out for: wind outdoors can blow the shielding gas away. Flux-cored wire is often used instead in exposed conditions.
- You will also need: a gas regulator, the right contact tips and nozzles, and a torch rated for your current.
TIG welding (GTAW): precision and clean finishes
TIG uses a non-consumable tungsten electrode, and the welder adds filler rod by hand. It is slower and needs more skill, but gives the cleanest, most precise welds.
- Best for: stainless steel, aluminium (with an AC-capable machine), thin material, pipe root passes and visible welds.
- Watch out for: lower deposition rates, so it is not ideal for large volumes of heavy welding.
- You will also need: argon, tungsten electrodes, collets and cups, and a torch that suits the job.
Stick welding (SMAW / MMA): tough and portable
Stick welding uses a flux-coated electrode. It needs no shielding gas, so the set-up is simple and it copes well outdoors, in wind and on less-than-perfect surfaces.
- Best for: site work, repairs, maintenance and thick sections.
- Watch out for: slag must be chipped off after each pass, and it is slower than MIG for long runs.
- You will also need: electrode holders, earth clamps and the right electrodes for the base metal.
Other things to check before you buy
- Duty cycle: the percentage of a 10-minute period a machine can weld at a given current without overheating. Heavy production work needs a higher duty cycle.
- Power supply: confirm whether your site has single-phase or three-phase power.
- Current range: make sure the machine covers the thickest material you weld.
- Consumables and spares: choose a machine whose torches, tips and parts are easy to get locally.
Talk to us before you decide
Fong Yung Industries supplies welding machines, torches and consumables for all three processes. See our EVO-MIG, EVO-TIG and EVO-Arc ranges, or tell us about your job and we will recommend a set-up.