Welding Tips and Tricks

alright guys, I had to do a little project for the father inlaw out of alum. 1/4 to be exact I have a diverion 180 wich is maxed out 3/16. anyway I figured I would be standing on the pedal to max amperage out, but actualy that was not my problem I seem to have other issues. There was certain areas where it seemed like i could not get a good cleaning effect and then other areas it was fine. Not sure if it was me or material or tickness of material or all of the above just seemed like a real battle. I was using 1.5 lanth. gold tungtson 15 cfm on the argon and filler was 3/32 4042. Now I realize I was outside the limits of the machine is it maybe that the dcen and ac balance are preset for the 3/16 thickness and I was outside that range? I got the job done and it is acceptable but I have done much better work within the parameters of this machine on aluminum and was just curious

on your input thanks, Eric

By the way guys I did do the proper cleaning with a stainless brush and alcohol wipe down.

I can't speak for that particular machine, but it's not uncommon to have less-than-ideal results when operating a machine at it's upper limit. Did you stay within the listed duty cycle? If not, heat build-up in the machine may have caused the inconsistent results.

It probably wasn't practical for a quickie job, but adding helium to the argon would have helped a lot, allowing you operate at, say, 80% of max, with a result probably 120% of max with just argon.

Steve S

This has been brought up to me before however trying to get helium is like a joke at my lws. Is there realy that much of a difference in performance between the two ? Do I need to get looking somewhere else when my argon goes empty? I have never welded with it so im kinda blind to its benefits.

Mixing up to 50% helium with your argon will bump up your "effective" heat on aluminum by at least 50%. Welding at 150A will feel more like 225A.

It's not cheap, though, as you can't just use "balloon grade" helium... Too many trace gasses, including oxygen, in it.

I'm fortunate to have all the high-grade helium I want at my work. I seldom do aluminum, and even more rarely is it a heavy enough section for me to set up the helium as I have Miller SW-250s, but it makes a huge difference when I do use it.

If you only rarely do work that maxes out your machine, it's probably not worth the investment.

Steve S

I would also like to add why do I periodicaly get that pepper look in the weld, Does this have soemthing to do with the dcen and ac balance ( something that I can not adjust) or is this something in the material such as debris or some other type of contaminent?

Often, "pepper" suggests the arc balance should be backed down toward "cleaning", but if yours is fixed, it should be fixed at "balanced", and the only option is to clean more thoroughly and/or turn up the gas a little.

I don't use any chemicals on aluminum, just a grinder and a wire wheel, unless I start with greasy metal, which I'll hit with laquer thinner first.

Thanks for all the info. it is much appreciated. I have had my diversion180 for about a yr now and am pretty comfortable on the dc side still learning on the ac end as most of my work is steel but, still would like to bring my ac game up to the level of my dc. All in due time that why I take on all these little projects I guess. Thanks again Eric

Another thing you can do is to put a small preheat on the material. Most alloys of aluminum will alloow a preheat of around 200 to 250, becareful cause some alloys you can't preheat. Most of the common alloys will allow it. This will help you not Max the machine out as well. It can be done in a oven or just a oxy torch and temp gun or temp crayons. Machine will act funny sometimes when you are maxing them out for long periods of time. I have never experienced your cleaning issue usually its the stability of the arc or you will loose your amperage.

Thanks for all the insight guys much appreciated, Like I said before under normal conditions this is a great machine. It does not have all the bells as some others but it only cost half as much to However I sure would like to have pulse option but it will do for now. Thanks again guys sure love this site!

sometimes, when the weld path has different obstructions and such the argon dont flow nice to the areas causing it to not clean as much. you didnt say what size cup you were using, but in my experience i find larger cups work better. i like 7 and 8 cups for aluminum. i get better coverage and better cleaning when i use a gas lens. i get better cleaning and most times use less gas flow when i use a gas lens. i know they are not always required but in my opinion it helps.

"Does this have soemthing to do with the dcen and ac balance..."

Not sure I understand what you mean here. Are you referring to the balance of electrode negative versus electrode positive in the AC current? I don't think DCEN is really applicable. Just a newbie myself and know just enough to be dangerous.

Nils

i forgot to add in my first post that there is a helium shortage. from what i understand any one who doesnt already have helium wont be able get any for 2013 for sure. if you have a contract already, then they have to get it for you. this is the information my local welding store gave me because i wanted to get some. looks like i will not be able to do this anytime soon. so it probably won't do any good to suggest helium, at least not for the people that dont have it already.

I was actualy using a #6 cup, I here of people using these lenses do they just give a wider blanket of gas ? Or is there more going on there? I am no master by any means with aluminum ( or mild steel for that matter) but I have put down some nice dc and ac welds when I stay within the limits of my machine. Im not trying to say that it was the machines fault by any means believe me Im still learning aluminum and still working on my technique so im sure alot of it had to do with me, im just simply saying i have never had these issues when i was in the comfort zone of the machine thats all.

Im going to mess around a bit on some scrap say 1/8" and then maybe try a small piece of 1/4 again and be sure i use the same cup, technique etc... and try to see if I can come up with something. It could be and probably is me this is actualy only the second time I have tried to weld 1/4 aluminum ever so like I said Im still learning. I will keep at it can only get better right? Just thought I would try and gain some knowledge of whats going on thats all. I will update when I get back at it and let you know thanks again guys, Eric

When I started working where I am at now, they had lenses on all the torches. In my type of work, it doesn't make much of a difference if at all. At least where welding around tight radii are concerned. The enlarged cup size has a cancelling effect with torch angle in my situation as I am often behind the cup as often as I am in front or directly above it. On traditional weld joints it may make a difference where you can keep a consistent angle of perspective, but in no way substitutes technique. In welding school, I arrived at textbook quality welds on aluminum without gas lenses thru practice alone. The best approach at learning to weld aluminum is to start out going by the book with regard to tungsten stick out, cup size, amperage, gas flow rate etc, getting that down pat and then customizing your approach after the fact.

The "helium shortage" is as bogus as the oil shortages of the '70s.

It's a supply chain delay, the prices are high, and commercial customers have preference.

I work directly with gas producers, and none of them are aware of the alleged shortage. I don't have to buy it; I have as much of it as I want at work, and we waste some.

Once shale gas production reaches equilibrium, this perceived shortage should go away.

Steve S

Can you back purge tubes with helium?
I know its heavier than air, but can you fill pipe and tubing with it since its so "cheap"?
John

AKweldshop wrote:Can you back purge tubes with helium?
I know its heavier than air, but can you fill pipe and tubing with it since its so "cheap"?
John

Um...

Much lighter than air.

I do use the hell out of it... I've used a 280 cu ft bottle in 4 hours.

I'm not buying it, though...

Steve S

And, yes, you can back-purge with helium.

Why, though?

Steve S

Just wondering, My friend gave me a half-full 74 cu ft bottle of helium, to use when tigging thicker aluminum....
Was just wondering if it would work, so I could try it out ....
John

Using it for back-purge is a waste. On any material.

Save it until you can use it for a shield-gas mix on something heavy, and see what the big deal is!

Steve S