If you've asked a welder to quote for a broken gate or a wobbly handrail, they may have asked whether it needs MIG or TIG. The answer changes how long the job takes, what it costs and how the finished weld looks. Here's what the difference means for jobs around Dartford, in plain terms.
MIG welding feeds a wire through a gun, and a shielding gas protects the weld as it forms. It's quick and forgiving. It works well on mild steel from about 1mm up to 10mm or more. The weld bead is wider and there's some spatter, so visible joints usually get ground back and painted.
TIG welding uses a tungsten electrode, and the welder feeds the filler rod in by hand. It's slower, often two to four times slower than MIG on the same joint, but much more precise. The welds come out neat and narrow, which makes TIG the usual choice for stainless steel, aluminium, very thin sheet and any joint that will be on show.
For most household steelwork, MIG does the job well and keeps labour costs down. A properly made MIG weld on mild steel is very strong.
TIG makes sense when the metal or the look of the weld calls for it. Stainless balustrades and handrails, which are common on newer homes around Greenhithe, Ebbsfleet and the riverside flats, almost always need TIG. A clean stainless weld can be polished back so the joint barely shows. A MIG weld on the same rail would look lumpy and could discolour.
Aluminium is the other main case. That includes cracked alloy castings, aluminium gates, boat fittings and some vehicle parts. Aluminium conducts heat fast and melts without glowing first, so it needs the fine control that TIG gives. Thin stainless exhausts and delicate sheet work also suit TIG, because MIG can burn straight through material under about 1mm.
Because TIG is slower, the same length of weld costs more in labour. A gate hinge that takes under an hour with MIG could take two hours or more with TIG. For painted steel you'd be paying extra for a neatness nobody will see.
Pricing depends on access, materials, whether the work is done on site or in a workshop, and how much preparation is needed. Many welders in the Dartford area charge a call out or first hour fee. Beyond that, small MIG repairs are often a modest fixed cost, while TIG work on stainless is usually quoted per job once the welder has seen photos.
Around Dartford, finish matters as much as the welding process. Damp air off the Thames and road salt on the A2 and A282 corridors mean bare steel rusts quickly. Whichever method is used, ask how the steel will be protected afterwards. Good primer and paint suits most repairs. Hot dip galvanising, which a fabricator can arrange, lasts much longer on new gates and railings.
You don't need to know the answer before you call, but a few quick checks help a welder quote accurately and turn up with the right kit.
Often, yes. TIG relies on a gentle flow of shielding gas, so windy or exposed spots may need screening. Sometimes the part is better taken back to the workshop and refitted.
Not automatically. Both give strong joints when done properly, and strength depends more on preparation, penetration and using the right filler than on the process.
Usually, with TIG, as long as the metal can be cleaned properly. Castings soaked in oil or badly corroded can be unpredictable, so a welder may need to see the part before saying whether a repair is worth doing.
Tell Michael about your job. Drop a quick message with what needs welding, where it is and a photo if you have one. He will come back the same day.