200DX and my first TIG arc - wow!

[EmptyNester]

I had hoped to start playing with my new 200DX over Christmas, but it just didn't happen.

I set time aside today, watched some basic videos and gave it a try. Wow - I'm blown away at how much cleaner and easier to control it is over MIG. I don't know anything about TIG, but the 200DX seems really sweet.

I'm using 3/32, 2% Lanthanated, 2T and a gas flow of about 6 on 5/16 carbon steel.

Some of the videos I saw said to start practicing without filler, so that's what I did. Initially I had it at 60 amps and barely got an arc. After the bare minimum RTFM time, I went to 200 amps. Here's what I got after a couple passes:



On the lower amp setting I hit the steel a little. I don't know if that's what affected the tip, or if it was something else.



I never imaged this could be so much nicer than MIG.

So, a couple questions:

For just practicing running a bead, are those the right settings?

Any feedback on the bead? (After MIG it seemed like a thing of beauty to me, but I know I have a lot to learn.)

When an electrode gets to the point shown, does it need resharpened or can it still be used?

On some of the earlier passes, I got a lot of fairly big holes. What's the cause of that?

Thanks

[Rambozo]

TIG is a scalpel while MIG is an axe.

Are you using the pedal? It will help you to learn just how much power you need. You want to use just enough power to make the weld but no more. 5/16" plate is pretty much at the limits and then some, of that machine for a single pass weld. Probably better off to lower your power and do multi-pass welds to join it. For just running beads for practice, it's ok, but again I would back down the power a little, and that will take care of the holes. You will learn more if you work with 1/8" or even 1/4" for your practice pieces. They are more in the machine's comfort range, and will teach you more about what is too much power. If you touch the tungsten to the puddle, you need to stop and regrind the point. That the point isn't sharp is not as much of a problem as that it is contaminated with steel. For some things you will want a needle sharp point, but with high power, you may knock a small flat spot on the tip to allow it to handle more current. Overall I'd say you are looking real good.

[performance]

For steel, you'll rarely need more than 120 amps. More like 80-90 amps in general. For 3/32 200 amps is a little much and can blow away the tip. Go to 1/8".

[Markcuda]

TIG is a scalpel while MIG is an axe.

I like chopping down trees fast

[EmptyNester]

I like chopping down trees fast

I can't tell you how many things I've screwed up because "if a little bit is good, a lot has to be great!"

[Grizzly1944]

It goes like this. If a guy who does tig welding tells you that he never has dipped his tungsten into a puddle, he's lying.

Practice, Practice, and then Practice some more.

Have Fun!

[youngnstudly]

When an electrode gets to the point shown, does it need resharpened or can it still be used?

On some of the earlier passes, I got a lot of fairly big holes. What's the cause of that?

Thanks

Anytime you see the green cone around your arc, the tungsten is contaminated. Even when you barely get base metal on the very tip of the tungsten, a smaller green/aqua colored cone will usually appear. If it's really contaminated, you'll see the cone become much larger and the arc will start wandering (dancing) uncontrollably, especially if you increase the amps. Too many amps of any kind will cause blow through (holes) in your base metal.

Everyone seems to have a slightly different way of grinding tungsten. I've tried grinding different tapers and points over the years, but I always go back to the way I was originally taught, since it seems to make things easier for me.

The procedure goes like this for most steels, stainless, etc:

First. break (or in your case with a lanthanated tungsten, grind) your 7" tungsten in half, so you have two 3-1/2" long tungsten electrodes.

Next, sharpen both ends of each tungsten until you have a smooth 3/8" taper that is needle sharp, OR almost needle sharp (maybe a blunt needle?). Using that long of a taper allows you to flip the tungsten around after you contaminate one end. With a short taper, the contamination usually forms a ball on the end, which prevents you from being able to insert the contaminated end back into the torch (collet).

Having the other 3-1/2" portion of your tungsten sharpened and sitting in the pocket of your striped monkey shirt means you can contaminate each tungsten twice before you actually have to get up and resharpen tungstens. You'll be at the grinder all day if you sharpen one tip at a time and then contaminate it 30 seconds later!

I probably shouldn't mention this, but occasionally if the tungsten is BARELY contaminated, or you let it touch the hot weld puddle while you were lifting your welding helmet to check out your weld, you can weasel your way out of resharpening by striking an arc on a heavy piece of scrap steel, and "pumping" the pedal up and down from low amps, to high amps (say 100 or more) without letting the arc go out you lose the needle point, but don't need it unless welding thin sheet metal anyways).

Sort of like revving your car's engine up 4 or 5 times when challenging the soccer mom in the lane next to you to an unofficial race between stoplights. Most of the time though, you need to sharpen the tungsten.