WHICH TIG WELDER?
There are lots of choices out there when buying a machine. It’s difficult to know which one to go for. TIG welding is considered as being the most skilled welding process mainly because of its use in “cosmetic” applications. For this reason, having the correct machine for the job which will produce less spatter and sparks is a must. The TIG power source should be able to provide heat control and a voltage range to deal with the thinner materials being welded and this is something that only a good quality machine can achieve.
Duty cycle is basically a percentage of time that a machine will run before overheating at a set amperage. As with all welding machines, a good sign of a quality machine is its duty cycle. A low cost machine may offer a duty cycle of 10% at a set amperage, whilst a more expensive machine may cope with a 70% duty cycle at that same amperage. It’s also worth noting that some manufacturers may quote their duty cycle figures high because they have been measured at lower starting temperatures or over smaller time periods. The percentage figure refers to the amount of time over a set period, the welder can run for at a specified current before it overheats ie 30% referring to 3 minutes out of 10, for example. A welder in a commercial setting is going to need a machine that’ll run for longer before overheating than an occasional user.
You will notice that higher quality machines will have wider amperage ranges. Having this range allows welding of a larger variety of materials and thicknesses. A fabricator may be better off with a machine due to the range of materials they will be working with, whilst a welder with a set process may be able to use a welder with a lesser range.
DC TIG machines don’t have the capability of welding thinner materials like magnesium and aluminium. Again, AC/DC power sources come at a price but are worth it if you want a more versatile machine. Aluminium is a self-oxidising metal. AC current puts heat in one half cycle and removes the oxide layer on the reverse polarity. The electrode negative cycle puts electrons into the surface which collect under the oxide layer. The electrode positive cycle then lifts the oxide off.
A TIG welder with a pulse regulator (many machines come with this) controls the heat input into the weld and hence the heat during penetration. This is an important factor in choosing your machine. If you cannot control the heat input, you risk warping of thinner materials during the weld.
Fit for purpose and Built to Last
Buying any welding machine should be an investment. Having foresight into your welding “Career” will ensure you buy kit that will last. Buying cheap can be a false economy as the chances are, the machine won’t last as long, may be more difficult to use (due to poor arc stability and arc starting) and might not do everything you want it to do. Like everything in life, you get what you pay for. More expensive machines generally have better quality components making for higher duty cycles and longer life expectancies. Some TIG machines also allow the user to stick weld, offering more versatility.
Here at TBWS, we only stock welding equipment we deem to be of good quality. If you are unsure of what to buy, please call for advice.
Our website only contains a snapshot of what we can supply. We offer Mosa, Jasic, Cebora, ESAB, Parweld, Tecarc, Xcalibur and others.
You can find our TIG welder Selection here.