Welding Tips and Tricks

I'm a relatively new TIG hobbyist, and just picked up a 2014 Miller Dynasty 200DX. In the past, I had welded with an old Miller DialArc HF, and became pretty used to the way that transformer machine worked. So far, I love everything about the 200DX, except for its default arc start.

I had been welding a lot of aluminum plate, using the factory machine settings, and a 3/32 lanthanated tungsten sharpened to a point. What I noticed was that at arc start, the tungsten was getting its tip blown off, and I was getting black soot on the aluminum. Everything I've found while searching online is related to the 200DX having hard-starts before BlueLightning was added, which is the opposite of what I was seeing.

My first reaction was that I had contaminated tungsten, so I: reground that same tungsten, tried a different angle, tried a different tungsten from the same box, tried a different box of tungsten, tried a different grinder, tried cleaning the aluminum plate more, etc. and always had the same result. The only thing that would prevent the tip from being blown off was to start out blunt. The other odd behavior was that on restart, the oxide zone always seemed twice as wide as the rest of the weld.

So today I started with a fresh tungsten, and grinder, and new aluminum plate, and went through the 200DX's user's manual. I checked out the factory parameters, and came across the fact that: with a 3/32 tungsten, in AC mode, the welder starts the arc in EP at 120 amps. This seemed excessive, so I started playing around with the start parameters in "GEN" mode. After fiddling with that for a bit, I set the welder at ".020" and just left it there.

The arc now seems to start fine, my tungsten no longer gets its tip blown off at the start, and I'm not getting any of the contamination I had before. Anyone else run into this, or is it just me? What do you guys use for your start parameters?

I usually set my machine with the start parameters "one smaller" than the tungsten size I'm actually using. So if I'm running a 1/16" tungsten, I'll use the 0.040" start setting. I agree that the pre-programmed parameters are a little harsh.

Why not set all that stuff off and set it from scratch?

alex4nder wrote: I checked out the factory parameters, and came across the fact that: with a 3/32 tungsten, in AC mode, the welder starts the arc in EP at 120 amps. This seemed excessive, so I started playing around with the start parameters in "GEN" mode. After fiddling with that for a bit, I set the welder at ".020" and just left it there.

The arc now seems to start fine, my tungsten no longer gets its tip blown off at the start, and I'm not getting any of the contamination I had before. Anyone else run into this, or is it just me? What do you guys use for your start parameters?

You're not alone in objecting to that violent BLUE LIGHTNING start.
'Normally'....I'll setup for gEN start of 20 amps for .040 to .062, 30 amps for 3/32.
I leave the rest of the gEN settings-alone.
If the point gets dull, then this low amp start has trouble getting lit,
but I can get 15 minutes arc-on or more without re-pointing.

On thin SS, AL or fussy jobs, I want just a tickling start to begin with, then just ease into
the puddle makin'; which still takes less than a second.

'Not Usually' ...I'll select the next size down in the electrode menu for a smaller 'BLUE LIGHTNING' start

Oscar's comment on scratch starting--I'm not going to risk contaminating that very important
electrode point with a scratch start, right out of the gate.

Oscar wrote:Why not set all that stuff off and set it from scratch?

I set the rest of the machine up from scratch, but these start parameters are part of Miller's Blue Lightning functionality. I like the feature; it starts an arc really consistently and at low output current. I just want it to be less intense. The parameters are separate from the rest of the welder configuration, and only last a handful of milliseconds during arc initiation. I didn't even know they were there until I went through the manual.

I think part of the 'problem' with the stock settings is that they don't expect you to sharpen a 3/32nd tungsten down like a needle, especially on AC.

I didn't mean setting the HF off for scratch-start tig welding---I meant disabling the Blue Lightning feature and simply setting everything "from square one", to put it in different wording.

That's what the gen setting effectively does.