250EX very strange welding, was I given something other than pure argon??

[Gandalf]

Hello,

I have been welding with the 250EX for a year and half now, with flawless operation from the machine. My welding skills are progressing. I am mostly doing automotive projects, aluminum, with the occasional stainless. I never needed more than 120 amps up to this point.

I switched in a fresh bottle of argon today, flipped to AC, and tried to tack an aluminum throttle plate to a manifold. I got a weird discoloration, erratic arc, and no puddle. I grabbed a piece of 1/8" aluminum plate and tried to run a few lines to test things out. The arc was dancing around, making these strange tiny pits and circles, lots of black speckles and creamy-yellow discoloration beside the attempts at lines. I played with the amount of argon flow... it made no difference in the look of the outcome. The flow sounded and felt normal. The tungsten wasn't burning up, but looked black and shiny. Freq and pos/neg dials were about noon, also quite normal. TIG high freq start was fine. No pulse used. There is decent penetration.

This is what I am suddenly dealing with.... here's a pic:



I could be having a large brainfart (???) But I cannot figure it out. I really haven't needed to change much of anything recently besides flip the switch between AC and DC, and nudging the amps and the flow. And it's not how clean the aluminum is. This was set at about 80 amps, and a new tungsten.

Can the argon they gave me be something other than pure argon?

Any help much appreciated!
-Martin

[Rambozo]

Have you tried some steel?
It sure looks like a gas issue.

[everlastsupport]

Yea, best idea is check DC.

It's possible you have a bad tank, moisture (for CO2) in it. Can you ask the LWS to swap it for you. Seems like a pain, but it has happened.

Does the amp display max out at 250 when you ramp it up? Check the o-ring in the torch cap if you have remove the cap recently. When you open the tank and turn it back off, does it hold the pressures on the gauges until you bleed the lines?

[5440]

I was welding Al a week ago using the 250EX and ran out of Ar on one tank. We had an Ar tank for the spool gun that I tried. I started to get the pepper in the welds. Cleaned the metal and still similar results. So I got the empty tanked filled and welds seem ok....so as suggested, try a different tank.

[everlastsupport]

I was welding Al a week ago using the 250EX and ran out of Ar on one tank. We had an Ar tank for the spool gun that I tried. I started to get the pepper in the welds. Cleaned the metal and still similar results. So I got the empty tanked filled and welds seem ok....so as suggested, try a different tank.

Was the tank for a steel spool gun with aluminum wire or steel? It not aluminum wire MIX (4043/5053..) it is a mix of argon and CO2 and that would run hot and nasty for sure.

[performance]

Are you using a water cooled torch with a water cooler? It could be a pinhole in the torch gas line or a leak somewhere in the torch head as well.

[Gandalf]

I am just using the torch that came with the 250EX. The only way I could see a hole getting in the torch gas line is if it got a drop of melted metal through it somehow. I will check with stainless tonight and see if it also misbehaves then. Torch cap o-ring looks perfect. Can the torch have a "heat injury"? I really haven't cranked it up past 120 amps.

[everlastsupport]

I am just using the torch that came with the 250EX. The only way I could see a hole getting in the torch gas line is if it got a drop of melted metal through it somehow. I will check with stainless tonight and see if it also misbehaves then. Torch cap o-ring looks perfect. Can the torch have a "heat injury"? I really haven't cranked it up past 120 amps.

It is possible, but the torch is pretty tough. Why we ship it as a starter (and get killed on the complaints). And if you run 120amps or less, you are pretty much OK without a cooler if you know what you are doing.

[zoama]

Can the torch have a "heat injury"? I really haven't cranked it up past 120 amps.

If you were using the water cooled torch without water @120 amps AC, it may be damaged. AC puts much more heat into the torch.

[performance]

Mike,
Given the torch isn't even designed for air cooled and the fact that there is no argon flowing over the power cable, I would not recommend that they be used at all. Many torches have a "fuseable link" that will blow if they are run dry. The circulation around the torch head itself is different which helps cool it down as well.

Yes you can get problems because the joints for the connections are soldered in...and the torches definitely get hot enough to melt out solder.

[Gandalf]

I always start lower amperage than I need and nudge it up too, so I rarely am too hot. The torch has got hot in my hand after longer stretches, I stop then, but usually its all small pieces. I would say I have had the welder up to 120 amps perhaps 4 or 5 times in total, for welding smaller pieces of thicker aluminum to thinner pieces, but never needed for long periods at that amperage.

I tried stainless tonight, and it behaved much better, a bit of jumping around at the start, but I was able to run a line. It sounded/behaved fairly normally. Forgive me, I was in a hurry... it's the upper bead. This is my practice piece of stainless, the other bead is one of the first I ever did. Notice that, unless its my imagination, there is that same milky halo... I don't remember seeing that before. This is at 70 amps, 1/8" stainless plate.



Generally, I find stainless to be faaar more forgiving, so I am not convinced that the problem isn't affecting both types of welding, its just that stainless tends to put up with more impurities (surface etc)... perhaps the argon has a worse affect on aluminum? Again I tried aluminum after, and varied the gas flow... no difference. The aluminum caves in, all peppered, before I see any puddle. Dipping any rod into it just disappears. I don't see any damage to the torch-line that wasn't there before, but I didn't pull the whole thing apart to have a look at the gas-line exclusively.

To answer a previous question: Yes, the welder cranks right up to 250 amps if I turn the dial all the way over... 254 to be exact.

[zoama]

That weld looks like air is getting mixed with your gas somewhere.

[performance]

IF a water cooled torch gets hot in your hands, it's too late...and the damage is done. The milky halo is likely for oxygen getting into the weld.

[Rambozo]

Is the Everlast torch some kind of exception, I have always been under the impression that you never use a water cooled torch without water, period? I know the CK fuse block is set to burn up somewhere around 6 amps without water, and WeldCraft torches and cables say to never run dry. From what I've seen it's more damage to the cable that happens first, before the torch.

EDIT: I answered my own question. From the manual:

"The LX and EX units both come
with a standard water cooled torch, which will
operate up to 160 amps as an air-cooled torch.
However, considerable duty cycle will be lost
when operated with air cooling only with the
water cooled torch."

I guess it comes down to the "considerable" loss of duty cycle. I know this manual is several years old, and perhaps there is a better warning in the newer ones, but it seems like these should either come with air cooled torches, or a much more specific warning about the use of water cooling and duty cycles for specific amperages.

[performance]

We stated that due to the torch suppliers original statement, but I believe it was a typo or misunderstanding.

[everlastsupport]

I run mine all the time under 120 amps and never had a problem. And because our site said it could be done. I will make note of the change, but I have done this for years (WP18 and 20). Never burnt one up yet.

[Gandalf]

Is there any way to inspect the torch? Is there a likely component that will be first to go? It likely isn't a solder-spot inside, it must have to do with a heat-distortion somewhere, allowing air in... or is this an incorrect assumption? A solder-spot would result in non-function of the switch, or some electrical failure.

I'll go and swap the tank this AM... I only used it for 10 minutes anyway, I think they'll help me out. That will narrow things down.

Also, to answer another earlier question: Yes, if I shut off the tank valve, the pressure gauge shows pressure, and holds it, meaning that there is no leak between the tank and the welder, and the welder itself still has good seal integrity. If there is a leak, it is on the torchline or in the torch.

Honestly, I am surprised, the operation thus far has been so consistent, forgiving (I can really play with the settings and there is a wide range of acceptable operation, including argon flow) and at times set-it-and-forget-it (turn it on and go, day-to-day)...

[performance]

Actually the melted solder is a real possiblity, as I have encountered the solder issue with customers before. It isn't the switch I am talking about, but the soldering of the copper tubing to the head, and the fittings to the tubing.

[everlastsupport]

I recall one way back too (solder issue in the torch handle). Also, maybe switch to the short cap and a different size collet and tungsten to make sure all the torch parts are mating up.

[Gandalf]

Actually the melted solder is a real possiblity, as I have encountered the solder issue with customers before. It isn't the switch I am talking about, but the soldering of the copper tubing to the head, and the fittings to the tubing.

Understood.