The Ultimate Guide to TIG Welders in Australia
Posted by Kym Morgan on July 16th, 2016
TIG (Tungsten Inert Gas) welding is the common term used to describe Gas Tungsten Arc Welding (GTAW).
Any welding Machine capable of Stick welding can also be used for TIG welding, however the level of TIG functionality may not always be good enough for professional results. A basic Arc (Stick) welder will often only allow what is known as “Scratch Start” or hobby TIG welding. This basically means that you must scratch the torch along the workpiece (a little like striking a match) to initiate the arc. For professional looking starts on your weld and for tricky surfaces like Aluminium, this is unlikely to yield the results the user wants, but it appearance and fine work is less of a consideration it can be OK.
TIG is regarded as the hardest welding skill to master. Along with basic torch control, the welder also has to master feeding a filler rod with their free hand. They may also require the use of a foot pedal to control frequency and amperage, and most importantly, understand the various settings on the machine and when to apply them. It is not possible to get by just memorising a few numbers as may be possible with MIG.
There are a number of important distinctions that set TIG welders apart. These are more than mere power supplies, and come with a wealth of features.
• AC/DC Functionality: The most important feature of high level TIG welders is that they can be used to weld all kinds of metals with precision and finesse. High level TIG welders will possesses AS (Alternating Current) and DC (Direct Current). AC will allows for welding of aluminium and other similar metals, where simple DC does not suffice. Even simple AC is not enough for the best results, but it is a start.
• High-Frequency Start: This refers to the method used for initiating the arc. Traditional, Scratch Start issee the Arc ignited by connecting the electrode to the metal. But this is not always feasible. The high-frequency start feature uses a very high voltage that can initiate the arc with as much as an inch between the electrode and the metal. Once the arc is established, the voltage immediately drops down to the set level. The elimination of the need for a physical arc start protects the tungsten electrode from contamination. It also improves the quality of the work and provides options for manual start switches, whether on the torch itself or using a foot pedal.
• Gas Flow Features: The shielding gas is an important part of the TIG welding process. The flow control features of TIG welders are designed to provide the maximum workability. Options like pre-flow and post-flow allow the gas to start before the welding starts to prevent any chance of oxidation at the start. Similarly, the flow continues after the arc is stopped to protect fresh hot welds. It is a simple feature that is easy to execute and provides immense benefits.
• Square Wave Output: Higher end TIG welders feature additional AC output control. Square wave output prevents rectification, the phenomenon where the arc sputters out when the AC current switches polarity. The same benefit can be obtained from a TIG welder with high-frequency AC output.
Frequency Control/AC Balance: The ability to control the duration the electrode spends in each polarity cycle when on AC output is crucial to obtaining desired welds for some metals. To put it simply, these features control the balance of penetration and cleaning. This is vital for welding magnesium or aluminium, but also useful when welding thin steel sheets.
About the author:
Kym Morgan is the marketing director of eWelders.com.au, a leading online specialty welding site in Australia. They sell a massive range of MIG Welders, TIG Welders, ARC Welders, Inverter Welders, Multi-Purpose Welders, High Function TIG Welders, AC/DC TIG Inverters, Spot Welders and Engine Driven Welders in Australia. Their mission at eWelders.com.au is to gather Australia’s best range of welders and put them under one roof.
