Jasic TIG Series - Lift TIG Arc Starting; HF TIG Arc Starting

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GUIDE TO TIG WELDING
Before starng any welding acvity ensure that you have suitable eye protecon and
protecve clothing. Also take the necessary steps to protect any persons within the welding
area.
Arc starng - li TIG (li arc)
Not to be confused with scratch start, this arc starng method allows the tungsten to be in direct contact
with the work piece rst but with minimal current so as not to leave a tungsten deposit when the
tungsten is lied and an arc is established.
With li TIG start the open circuit voltage (OCV) of the welder folds back to a very low voltage output
when the unit senses the tungsten has made connuity with the work piece. Once the torch is lied the
unit increases output as the tungsten leaves the surface. This creates lile contaminaon and preserves
the point on the tungsten although this is sll not a 100% clean process. The tungsten sll can get
contaminated but li TIG is sll a much beer opon than scratch starng, for mild and stainless steel
although these methods of arc starng are not a good opon when welding aluminium.
Arc starng - HF start
Non contact High Frequency (HF) start method is a high voltage and low amperage generated using a
spark gap assembly and is the most popular and generally considered best TIG arc starng method. The
High Frequency (HF) start generates a high frequency arc that ionizes the gas bridging the gap between
the tungsten point and the work piece. This touch-less method creates almost no contaminaon unless
the tungsten has been over sharpened or the start amperage is too high. It is an excellent choice for all
material being welded especially aluminium although unless you need to weld aluminium, you don’t
have to use HF start steel/stainless.
The HF frequency varies with the spark gap and can be around 16000 Hz to 100000 Hz depending on
spark gap width so consideraon should be given with this method as it can cause electrical interference
to nearby electrical equipment such as computers, CNC controls and phone systems.
If the spark gap is widened, the HF can become errac.