0 items in your basket
Total £ 0.00 EX VAT
MIG Gloves
TIG Gloves
Baseball Caps
Armguards
TIG Heat Blockers
Shop 55,000 Products
SERVICEDEPT.
RAPID BLOG
FEEDBACK
HIRE
Straight answers to the questions people ask most when choosing and using AC/DC TIG welders, especially for aluminium.
You need AC if you weld aluminium or magnesium alloys. These metals carry a tough oxide skin that melts at a much higher temperature than the metal underneath. On the alternating current cycle the arc breaks that oxide up, which lets you form a clean puddle.DC is the right choice for steel, stainless steel, copper alloys and titanium. An AC/DC machine does both, so it suits workshops that mix aluminium with other metals. If you only ever weld steel and stainless, a DC machine does the job and is simpler to use.
Each AC cycle has a cleaning half and a penetration half, and the balance control changes the proportion of time spent in each. More cleaning breaks up oxide more strongly but gives shallower penetration and puts more heat into the tungsten. More penetration gives deeper, narrower welds and less tungsten heating.Most operators use a modest amount of cleaning, then adjust for dirty material, thickness and joint type. Start from the settings suggested in the manual for your own machine and change one thing at a time on offcuts.
Frequency is how many times per second the current alternates. A lower frequency gives a softer, wider arc that is forgiving and suits thicker material or wide beads. A higher frequency gives a tighter, stiffer, more focused arc that helps with fillet joints, edge welds, thin sheet and precise control around corners.There is no single correct figure. Try a few settings on offcuts of the same material and joint type, and choose the one where the puddle is easy to steer and the bead looks even.
It depends on the current you use and how long you weld without a break. Gas-cooled torches suit light to medium work and shorter weld times, and are simpler because there is no coolant to look after. Water-cooled setups use a separate cooling unit and a torch with a coolant circuit, which keeps the torch comfortable and protects it during long, high-current welding.Aluminium often needs more current than steel of the same thickness, so water cooling is common for heavier aluminium fabrication. Check the duty cycle rating for the current you actually plan to use.
Start by checking what your premises can supply. Single-phase machines run from a single-phase supply but are limited in maximum output, and larger ones may need a higher-rated socket than a standard one. Three-phase machines suit workshops with a three-phase supply and give more power for thicker material. Multi-voltage machines adapt to different supply voltages.Output may differ depending on the supply you connect to, so check the data plate and manual for your own machine, which give the rated output at each voltage. Have a qualified electrician confirm the supply, fuse rating and cable before installation.
A power source is the machine on its own. A package normally adds the items needed to start welding, such as a torch, an earth lead and a gas hose, and sometimes a cooling unit or a remote control. The contents differ from set to set, so read the description closely.Check that the torch is the right type for the machine, with the correct connection and cooling method, and that the leads are long enough for your work area. If you are adding your own torch or accessories, confirm they are compatible with the machine's connections.