![background image](http://html1.mh-extra.com/html/r-tech/tig161/tig161_operation-instructions-manual_775152014.webp)
14
Gas post flow adjustment 1 – 25 seconds. The gas keeps flowing after weld has finished,
this cools & stops tungsten from getting contaminated.
Note: Gas pre-flow time is fixed at 0.5 seconds in TIG mode but no pre-flow time will occur
if the arc is restarted during post flow time as gas is already flowing.
13.
AC Squarewave balance (SP%)
SP% AC Squarewave balance control is adjustable from 30% – 70%
Set at 50% this provides balanced control for AC Welding. The machine spends
50% of cycle in positive mode which lifts the oxide surface off the work (power flows from
workpiece to tungsten) and 50% in negative mode which penetrates the work (power flows
from tungsten to workpiece)
30% is maximum penetration, the machine is more torch negative - 30% positive / 70%
negative.
70% is maximum cleaning, the machine is more torch positive - 70% positive / 30%
negative
With clean metal you can select more penetration and the machine will spend more time
penetrating work (negative part of cycle).
When welding dirty/contaminated material more cleaning may need to be selected, the
machine will spend more time lifting coating off the work (positive part of cycle).
For most AC welding we suggest you set machine to about 40% SP. This means 40% of
weld cycle is positive (cleaning) and 60% of weld is negative (penetration)
Tip. If you are welding close to the tungsten limits, I.E 160amps on a 2.4mm tungsten and
the end of tungsten is wobbling and falling off, turning down the SP% will give better
tungsten stability as the current is flowing from tungsten giving more penetration (negative
part of cycle - more penetration)
In AC mode if you set machine to 30%, maximum penetration and set the AC frequency to
150Hz or above, you can grind the tungsten tip to a point to give a much narrower arc and
the tungsten will stay sharper for longer.
14.
Arc force (Stick – SMAW only)
This provides better arc starting when in MMA stick mode, useful when you are welding
dirty/rusty material or cold/damp welding electrodes