Welding Tips and Tricks

Hi, my name is Dave and i am new to the forum. I just sold my old Miller Diversion 165 and bought the new Lincoln Square Wave 200. Im having a slight issue when welding aluminum. Im getting a popping when welding aluminum. It almost seems like there is an argon issue, but i did not have this problem with the same bottle of argon on the Diversion. It's almost like the arc cuts out for a split second in any setting. My settings are 120hz, 67%En balance, 15cfh, around 70 amps through foot control, 3/32 ceriated tungsten, gas lens, #6 cup, 1/16 4043 filler, welding on 6061 .065" wall tubing. Cleaning process followed was file edges square and smooth, debur inside with carbide debur tool, debur outside with fine file, scotchbright inside and out, then wipe down with acetone inside and out on microfiber towel.

It will even make this same popping without any filler rod, i have tried Arctime and 2% lanthinated tungsten with no change, tried going up and down with the argon flow. All torch parts are new. Aluminum is new. I did find that i am having a hard time keeping the Harris 601 5-30 regulator accurate under 15cfh. It takes more turns to turn down than to turn up, this should be linear with the flow rate correct? Please help if you have any idea. Thanks in advance.

I had the same issue with my Miller. What I found it to be was an iffy ground. I was just welding aluminum today and had that popping happen and I stopped and looked and sure enough, my ground was hooked to the table but not the work. Its like the welder cuts out for a second. Also too long of an arc length can cause it but it never happens when I ground directly to the work. You will get other suggestions but this is what my problem was. I get lazy sometimes and just ground the table but that will give you ground burns on your metal, especially aluminum. I try to ground to the work always. Hope that helps.

It happens with the ground directly on the part or on the table. I was able to capture what it was doing and uploaded the video to YouTube. https://youtu.be/v_JdCeC-jV8

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This is what the tungsten looked like after this video.

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Yeah...that's not the problem I was having with mine. I will say that in your video your arc length was way too long and that will cause it to become unstable. I didn't see the popping you were describing, just a very unstable arc. If you know how to tig and you didn't have this problem before then I would guess its your machines settings and I don't know anything about your machine. I can hear that your on AC but other than that I don't know. There are alot of excellent welders here who will be along to help. Good Luck.

The arc length started out around 1/8", but due to the pipe melting and cratering it looks larger in the picture. The problem does amplify when i pull the arc out longer. I have also tried a 1/16 tungsten and the lowering the argon flow and it still does the same thing. Amps were set to 50 in the video. I have also noticed that the arc seems hard to start and it takes a few tries. Also i do get a high frequency jolt whenever i touch the table or part with bare skin while welding. I am running a Nema 6-50 outlet that is wired to my panel with 10 gauge wire running about 25 ft to the panel on a 30 amp breaker. The outlet is wired with the 2 hot leads and the bare copper ground. The neutral is not connected. Not sure if that is contributing to the issue, but figured I'd describe it anyway.

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Looks to me like the arc was just wandering a bit. This happens to me at low amperage settings. Crank up the power a bit and see if it stabilizes. Some machines don't handle low current very well. Also, 3/32 tungsten is pretty big for that thin of material.

So i just tried again with the amperage set to 70, freq
set to 120 and balance set to 70. Argon set to 15 cfh. Fresh grind on a 3/32 Arctime tungsten ground on what i believe is 80 grit dedicated grinding wheel. Arc length was less than 1/8" as shown in picture next to a piece of 1/8" aluminum. This test was done on a 1/2" slab of 6061 with clamp directly on it. I even ran my 8 gauge ground lead (goes to an 8ft copper ground rod outside the door) that i have in the garage for powdercoating to the welding table and it made no difference. Last picture was taken after the video.









https://youtu.be/tQ2s6mhR7VM

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Also stepped up to a number 8 cup with the gas lens. Im also assuming that the tungsten grind is fine because its ground the same way i used to grind them for the Diversion and never had this issue with that machine.

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I thought of something....My machine has a setting for tungsten diameter, I am sure yours does too, did you check that and change it? Also, you referred to arc length as compared to 1/8" metal. That is not arc length, that is stickout and you should have way more than that otherwisw you can't see your puddle. Arc length is when you are welding, how close your electrode is to the puddle. You want to stay within 1/8" or so. Any farther away and your arc will get unstable and wander, among other things. Also, your machine doesn't have enough ass to be doing anything with 1/2" material, especially aluminum. Rule of thumb is 1 amp for every thousand of an inch..example...125 amps for .125 (1/8"). You may have to play with that but that will get you in the ballpark. I would go watch some of Jodys videos. They are great and he doesn't leave anything out.

You may need to ohm out your cable both the ground and the torch cable. You may have a bad connection inside the cable or broken wires. After you run a bead feel your torch cable for hot spots.

Ok. So this morning i put my ohm meter on my cables. Cold i got full continuity. After getting everything hot for a few minutes i found that the ground clamp specifically gains about 0.5 amps of resistance. I also changed out the arctime tungsten to a brand new 1/16 Ceriated and the gas lens to the standard collet body with the standard #7 cup with 1/4" stickout and holding a 1/16 arc i still get the same issues. This run was at 70 amps, 120hz, and 70en balance. Also at 15cfh argon.
https://youtu.be/7Wy4pdHRW_Y

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Have you opened the cover on your machine to see if there is a bad connection on the inside? I would check your torch cable as well I melted one down from a bad connection inside the hose.

This is a brand new machine, so i have been hesitant on opening the cover. I did check the torch cable both cold and hot and continuity was excellent. Zero resistance from the dins connector all the way to the tungsten tip.

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Dcstang67 wrote:This is a brand new machine, so i have been hesitant on opening the cover. I did check the torch cable both cold and hot and continuity was excellent. Zero resistance from the dins connector all the way to the tungsten tip.

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Do you have a local Lincoln dealer? Don't risk voiding the warranty, even if they're not local make a phone call maybe it's a known issue (?)

I called the place i bought it from and he told me i can open the case and inspect, but not to mess with anything. I did just that. Once opened this thing is encased with plexiglass and you cant get to anything without dismantling the whole thing. I didnt see anything wrong so i closed it back up. I also measured the voltage at the plug and im getting 236 volts there, so its not a low voltage issue.

Im really leaning toward possible argon contamination now. After filling the tank the last time i had already sold the other machine. I had forgot that i did that. Maybe it wasnt evacuated 100% before it was filled.

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I noticed that if i shut the bottle off and let it sit i lose about 1 scfm on the flow gauge every 3-4 minutes so i decided to check the hoses for leaks and i found a small one at the back of the machine where the hose attaches. I really had to crank down on the nut to stop the leak. I dont have a chance to fire it up right now because i am watching my 3 year old at the moment. Im hoping this is the issue. Do you guys think that could have caused the problem?

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IMO, I don't think a slow leak would cause the problem you describe. If you didn't have enough flow you probably wouldn't know it until you start welding. If you forget to turn your gas on, you will fry your tungsten back into the collet. If you don't have enough post flow, you will gray out your tungsten. Most gas systems have a tiny leak, that's why you need to be sure you turn your gas off when not welding. Plenty of guys find out about leaks after not using their welder for a week and leaving their valve open. Does this happen in DC on steel or only on AC on aluminum? Have you tried running any beads on aluminum that is the appropriate thickness for your machine? It will be hard to diagnose a problem by trying to create a puddle in a piece of aluminum that is way too much for your machine. After watching your video several times, my opinion is that your problem is very minor but if it's bothering you then you need to find the cause. Run some beads on thin material and let us know what happens.

I could not tell you if it does it in DC because i have not yet welded anything in DC with it. When i started noticing this i was running beads on some .065" wall 6061 tubing, i only set the torch up on the 1/2" aluminum to demonstrate on video what it was doing. The 3rd video shows more of what its actually doing. Sometimes it just cuts out once like the video and other times it will do it a bunch of times in clusters and very erratic. My Miller Diversion never did this and my welding style has not changed. This is the reason i am bringing this to attention.

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Is it affecting the quality of your welds? Is it blowing holes in the metal? See what it does in DC on steel. Pictures really help.

Its not blowing holes in the metal. Mostly it is just affecting the timing of my beads and is annoying at most.

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Can you watch the machine's amperage meter while you set up your torch and let it run to see if you are getting a voltage drop? My machine lets you see what your in-time amperage is at even though you can't watch it and weld at the same time. Maybe it's something in your input power.

It does display the used amperage but its hard for me to look at it while watching what im doing with the torch

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Video record the display then weld as normal