Even though I mostly prefer to have a foot pedal amperage control, There are times when only a a switch on the torch is really handy….like when tack welding airplane fuselages, or welding an aluminum tubing tuna tower.
When you don’t have a remote amperage control plugged in to your tig inverter, a torch mounted switch along with upslope and downslope controls can really help you get things done.
Remember , none of this applies when you have the pedal plugged in. and make sure to select the 2t when a pedal is used.
Not every single tig inverter made has the same controls but most of them have some things in common. Usually a tig inverter will have a 2t or 4t selection and some are labeled 2 t or “2 trigger hold”.
Whatever they are called, they all work kind of the same and understanding one brand names settings will usually help a lot in understanding the next one.
I happen to be using an Everlast Powertig 250 EX for this series of demonstrations. I have been using tig welding inverter welders for a very long time but I just learned this machine recently.
On my Everlast Welder that I used for these demonstrations, there is a rocker switch that is labeled 2t and 4t.
Its usually labeled a bit different on a Miller or Lincoln but On my Everlast tig welder, here’s how it works…
The 2t means that when you press the button , you get an arc….when you let off , the arc quits.
You have to hold the button down the entire time you are welding or the arc will quit.
The 2t setting can be used strictly as an on/off switch for tack welding or for welding thick stuff where amperage control or finesse is not needed. But the 2t setting can also be used with upslope and downslope settings to be more like an amperage control.
All you have to do is set the upslope knob to 10 and the downslope knob to 10 , the start amps to 1 and the end amps to 1 and now instead of an on/off switch, you have an arc that starts at low amperage, takes several seconds to ramp up to the main amperage, and then when you let off the switch, the amperage decreases slowly before it finally quits …all with 2 touches of the button.
Even though a torch mounted switch will never provide the fine amperage control of a foot pedal, there are a few tricks that make it really useful.
Here is what I mean…with the upslope and downslope set to 10 it takes a little time to fully ramp up to peak amperage and it also takes a little time to ramp down to a low amperage.
But if you are welding along and want less amperage for a few seconds, you can let off the trigger and the downslope will begin and your amperage will decrease.
By pressing the trigger again before the arc quits, the 2t upslope begins again and the amperage increases back to peak amperage.
You can do this as often as you like….anytime you want less amperage for a few seconds.
Its not the control you get from a foot pedal. But it’s much better than nothing.
Here is an example of how this could be useful:
Let’s say you are welding a 4 foot long weld joint and you just don’t want to stop. You put enough tig rods to make the weld on the table where you can grab one quickly with your helmet still down and the arc still going.
When you are ready for another rod, you let off the trigger, hold the torch still, and reach for a rod. while you do this, the amperage decreases as the 10 second downslope cycle runs, you grab another tig rod and choke up on it are ready to weld some more in around 5 seconds. When you press the trigger again, even though the downslope is only about halfway done, the amperage begins to ramp up again because the whole 2t cycle starts over and the upslope is kicked in again.
Hopefully , between this explanation and the video above ...TIG inverter settings part 3, the 2t position makes sense now.
So what is 4t?
With the 4t selector knob, there are 4 switch movements that basically do the same thing as the 2t…so it gives you a little bit more control over the cycle and lets you weld with less fatigue because you can don’t have to hold the switch down while you weld.
4t is this…
Press the trigger, you get an arc of whatever amperage you set the start amps. You might want a really soft start, or you can select a crisp hot start. A zero setting will start at really low amps. That’s usually a good thing but if you are using big tungsten like 1/8”, you may get an erratic start and need to bump up the start amps to get a sure start.
So position number 1 of the 4 t’s is pressing the switch, holding it down and getting an arc…Nothing else happens on the 4t position until you let off the switch. That’s number 2 of the 4t..when you let off the switch, the upslope begins and increases amperage until it levels out at the peak amperage. When you are ready to stop welding , you press the switch and hold it down( number 3 of the 4t’s) and the downslope kicks in and decreases amperage to the point where you have set your end amperage.
But you still have an arc until you let off the switch and that would be number 4 of the 4 t’s.