Powertig 200DX fairly new TIG welder

[Tritium]

Chevy,
A wandering arc is usually a result of one of about three, four, or possibly five things. ( You do have your torch in negative right?)
1) poor placement of the work clamp, not directly to the metal itself, having to route the electricity through the table etc.
2) Corrosion on the work clamp. Check to see how hot the clamp is. IF it is hot, you need to move it, or disassemble the cable and the clamp and clean all connections.
3) Contaminated tungsten, is actually one of the most common causes. Learning to tig is always a grind, regrind, regrind some more process.
4) Contaminated gas. Sometimes welding supplies get lazy and don't properly vacuum the tank before they fill it. Or they accidentally mislabel it.
5) Holding the tungsten greater than about 3/32 off the metal will cause a lazy start.

And 6) trying to weld in a breeze (in front of the welders fan in my case). The arc was all over the place.

Thurmond

[chevyracer56]

Tritium- I think I should be good there....my welder is on the ground beside me, but I am welding inside of my garage with basically no air flow (unless I purposely turn on a fan). But that is good the think about!

[performance]

Chevy, I just looked at the pictures again. The first picture in post 13 is a normal looking weld. Grayness, especially on an outside corner is going to happen. The only time a weld will be relatively shiny will be when you are down in a groove, running a root pass where the Argon will sink and hover over the weld for a longer period of time.
Most of the shiny welds you see welders making are hit lightly with a steel brush wheel before they are posted.

But also in the same picture, you have contaminated your tungsten from the "blow out" at the beginning of the weld. If you want to see better results Vee out a groove so that the plates are beveled on both sides and at least one inch is ground down with a grinder on both sides. I think you'll see a better weld, especially if you use a 70 s6 rod.

[chevyracer56]

performance- perhaps you are right and my mind is playing tricks on me.....perhaps the reasons I saw so many "shiny" welds when I did a 4130 chromoly chassis is because anywhere near the tube ends were polished before welding and once welded they had a colorful HAZ, perhaps all of that combined is why I recall the welds being shiny when in reality its just everything else made it seem that way?

On another note, I have been using er70-s6 rod, I used a little spare S2 rod i had laying around of known quality (the s6 I have came as part of the package with my welder). I will try beveling some thicker pieces later on and see what it does

Lastly I tried some more aluminum and the arc. is definitely more stable at the start than it used to be. I also realized why I might be having trouble with my filler occasionally.....it is 1/16", and even though I am only welding on 30-40 amps perhaps that is too much amperage for that tiny filler, I will source out some 3/32 perhaps.

[sportbike]

1/16 filler is fine.
When tig welding, you need to make sure everythign is shielded, including the hot end of the filler, otherwise, it will oxidixe every time you pull it out of the shielding gas, then deposit the oxided back into the weld.

I woudln't worry so much abotu the apparent oxidation you are worried with, instead, work on torck control adn steadiness with your filler.
Start with steel as the puddle is much easier to see.

somethign in teh 1/8" thick range will likely be the easiest, not too thick that it is hard to heat up, but not to thin where you ned to be on your toes to prevent overheating.

Stick your tungsten out of the cub the least amount practical, but be sure it is not like 3/8" out as that is likely too far to get shielding.

Sit at a chair, with the material on a table of some sort at about chest height.

Concentrate on watching the puddlt develop. Once the puddle is approxinately 3/16-1/4" diameter, then move the torch slightly without lifting or lowering it, then dip the wire into the puddle, move, dip, move, dip. lright, left right, left right, left...

Use lower heat rather than higher, just take your time. Don't focues on trying to penetrate the material either, you are just doing an autogenous weld on plate. No joint to worry abotu consuming or heat transfer from one side to the other.

Let the torch and filler hang out for a bit at teh end of the weld, while the post flow shielding gas is still flowing.

Lay a bunch of beads, abotu 1/2" apart, in as straigh t a line as you can manage. (Be cautious of how hot the material will get)

torch control, torch control, torch control.

Pay attention to your beathing as well. Be sure you actually are breathing and not holding your breath. I know that sounds trivial, but it is very important, otherwise you will not be abel to be steady throughout the weld.

It you heat it....it will flow.

[chevyracer56]

Sporkbike- Thanks for the advice, I will definitely practice some more as that is the only way to get good! I am really looking forward to getting my working foot pedal in, I originally "learned" how to TIG with a footpedal and it allowed me to just move my foot and keep a constant/stead pace with both of my hands which helped out tons, but now since I am only using the torch I am having to adjust my feed rate with both hands as the pieces heats up........it is definitely a bit more of a challenge to get everything looking consistent that way .

[performance]

That's why I tell people to start with the torch switch, because it develops technique and makes you a better welder from the start.

[chevyracer56]

I found an old piece of 4130 that I used as practice material a while back and decided to lay a small bead next to it for comparison.........the bead on the left used a dynasty 200dx with footpedal...it was set to about 60 amps but I was probably only using half, and the two on the right were with the powertig I had it set to 40 amp.....just comparing the difference in how shiny they are...both used 70s-6 rod and red tungsten.

Also is if you look at the two tungstens (1/16) I did a very small bead then removed the tungsten and it had those haz/scorch marks on them (single bead after grinding).....is that normal for them to form that quickly and where they are?

[performance]

Scorch marks are also a sign of lack of shielding gas, whether from flow, torch angle, cup size or gas contamination. The width of the beads suggest you are welding much hotter than with your dynasty...which is very possible. The Dynastys don't pack quite the punch of our inverters. I have a customer running Dynasty's side by side on a CNC welder with our 200DX's. The Dynasty is set at 120 amps, ours is around 98 amps. He sent a picture. He had a little shipping damage which we rectified as is visible in the picture, but here's your proof. Same CNC, Same duties, same everything, running simultaneously, but different welders.

[chevyracer56]

Performance- whatever is causing the scorch marks on the tungsten, could that also be why I am having the slightly grey welds (if there isnt enough gas for the tungsten I doubt there is enough for the workpiece).

Yes you are right about the powertig penetrating more and being a little hotter than the dynasty as is evident by the penetration when viewed from the back side (I doubt my phone would capture it well enough).

Anyhow, with a fresh collet and tungsten and with varying the flow rate a good bit, what else can I try to remedy that situation? I am using a #7 cup already.......perhaps a different set of consumables altogether ?

[performance]

I'd try using a number 5. Sometimes bigger isn't better. Go lower on your amps.There is a big difference in the weld you laid down on the dynasty and on the Everlast. Its about twice as hot from the looks of it.

[chevyracer56]

performance- I will try that for sure, honestly with the dynasty I usually used the smallest cup I could find b/c I was doing tight corners, but I will try some smaller cups and report back.

[chevyracer56]

Hey everyone, I just thought i'd give an update after my week long beach vacation ......I was going to get a new torch but thought i'd try a cheaper route first and picked up a new collet body and 2 collet's and #6 gas lens/cup all for $13 and got a new tank of argon......I am not sure exactly which made the difference, I am assuming the gas lens but my tungsten are no longer instantly contaminating or getting any HAZ/scorch marks and my welds are coming out more shiny like I was used to. In short if you have a local airgas or similar welding supply store I highly recommend getting a gas lens . This is not to say my welds are perfect yet but it does help being able to see a difference....for instance I think I still need to slow down a little in the middle of the beads b/c it has a slight haze to it that I am assuming is due to lack of coverage (so either slow speeds or bigger nozzle needed?).

[chevyracer56]

Also aluminum welds seem better and different....the machine doesnt seem to be getting as much penetration for the same amperage but is producing a much better bead with a lot more cleaning. Again these are by no means perfect and could probably have used a little more penetration but it is getting better

[Ram48]

Hey Chevy
I really appreciate this thread. I am in the same spot with my welding Working on the dip in and out thing and am also getting the scorch marks on the electrode and grey welds. I do have a gas lens and a number five cup but My gas may be a bit low I will check during playtime tomorrow.

[chevyracer56]

Ram48- Its no problem, that is what forums are for . I did notice another difference that I forgot to mention, then weld puddle actually seems more stable....but I assume that is due to the lens making a uniform flow of shielding gas. The scorch marks on my tungsten used to be right at the tip of the collet body.....I compared the oem one with the weldcraft one I got at airgas and the weldcraft one has a slight different design and fits a little better.....I dont know that is what my problem was since I changed a few things but I think a collet and collet body are only like $1.50 each so it cant hurt to get a new one. Plus the oem I had deformed after a short run at 200 amps anyhow. Also with the gray welds try lowering the amps some and slowing down, that helps, but only once you solve your shielding gas problem. Lastly check for leaks....a while back I thought my hoses were tight but the one going into the machine would leak a little if you pushed on it and cause tons of porosity.....so make sure everything is tight

[chevyracer56]

I decided to do a quick test on a rusty piece of steel I had laying around, I took a sander to it but no acetone. I did three tests....new collet and gas lens, old cup new collet body and collet, old cup old collet old collet body, respectively. Honestly, though there seemed to be some minor differences, I think the gas I had in combination with possibly poor torch control and possibly argon leaks were the culprits of my prior issues. Anyhow I hope to get some more pictures of a different type of weld (instead of just plate).... but I think torch angle/flow rate/cup size and good cleaning are the main things I will be concerning myself with for now.

btw the only significantly noticeable difference that I can visually tell between my tests is the gas lens provided better shielding at the end of the weld (hence little discoloration)(far left)

[chevyracer56]

So I finally got my foot pedal in .....except it is most def. used and does not have any amperage control knob like my previous one....so now I have zero control over the pedals output (aside from my foot of course).......but the pedal does work which is more than I started off with.



*edit* Another possibility to the pedal aesthetics is poor surface prep when it was painted....but pedal works so I am happy with it. I will be opening it up soon to see if I can swap the rehostat over from my other pedal so this one is adjustable.

[chevyracer56]

Just thought i'd post some pictures of a aluminum single step that I am making for my trailer. One thing I learned is that it is hard to maintain torch consistency when your hand is on fire lol....I suppose I could have taken a break though........but I was mostly doing 3" sections and then joining them, mainly b/c its hard to smoothly move my hand on my "work table" and I kept running out of filler and needed to adjust.

[chevyracer56]

So I finally swapped parts between the two pedals I have and it works, yay......although I wonder if it should be adjusted at the potentiometer...it reads -20 and as you increase the pedal it eventually goes to zero, but until that time the arc is very erratic.......regardless the arc stabilizes on aluminum around 10 amp (according to the display) so I decided to run some superficial beads on .060 aluminum sheets and a energy drink can. Aside from the arc swirling around sometimes (probably due to me grinding tungsten on a bench grinder) it works surprisingly well on the low end. My beads would have been more consistent on the can except I couldn't hardly move the torch without hitting the shelving above me lol........anyhow thought someone might be interested