New inverter stick welder - sizing advice

[frugalangler]

I'm looking to replace my 295A stick welder with a new IGBT inverter unit, I don't need the capacity the 295 gives me, but I would like to get a feel for what different amperage class welders are capable of.

I'm somewhat limited in source power, I've got a 20A 220V available so I can't go above that, and have found a few machines that run about 125A to 150A output

My question: What approximate material can this practically weld? I understand duty cycles, etc. but will it be capable of running a 3" long butt weld of 3/16" mild steel?

I'd like to get some real world experiential data - if I'm out of the league for that thickness then I'll have to bite the bullet and pull a new circuit - spell expensive - as it's quite a long run from my panel to where my welding area is.

Thanks, and yea, don't beat me up as I'm not going to buy a Miller or Everlast, I just can't fit that in the budget, but I've had great experience for my purpose with the import machines (my CUT-50 plasma kicks butt) so not afraid of them.

 

[GLyford]

Grab a package of the size and types of welding rods you are thinking of running, most will list the recommended amperage, and it is usually pretty close.

In my limited experience, 3/16 mild will be pretty forgiving.

For mild steel, you are probably running 6011 or 7014, 7018 will work but it is overkill (not that that has ever stopped anyone).

On 3/16 material, you can use either 3/32 or 1/8 rod. If we assume 1/8, then 6011 is listed as 70-120, 7014 as 100-160, and 7018 as 90-160. 125 is in a pretty good sweet spot in the middle of that, so I think you would be good to go. Or back off to 3/32 rod, most top out at 100A and you can run longer before the machine shuts down. If you aren't happy with the level of fill, you can always make two passes.

If you are doing any amount of fitting, peening, slag hammering, brushing, etc., you will likely never run into your heat limit on 3/32 rod. If you run 1/8 and have a whole trailer tacked up to weld and go into constant production mode, you will likely keep tripping it and be unhappy and want a bigger machine. I have a "160" IGBT machine and have only tripped the duty cycle once. But for one 3" weld of 3/16 mild? It sounds like the proposed machine will be a good fit for you.

Electrode Amperage Chart

 

[frugalangler]

Exactly what I was looking for, it's been so long since I did stick and I NEVER had the luxury of having the package for the rods, as they came under the table so to speak, and the chart I was aware of but my memory cell depletion must have obliterated that.

I was hoping based on other reading I'd done that this would go, since new inverter welders supposedly weld hotter (less amperage) I was thinking I'd be good.

Again, thanks to you GLyford and all the others here at TBN for all you do

 

[k0ua]

1/8 inch 7018 runs very well on my Everlast PA160 at 125 amps. See below.
I bet that will run on your 20 amp circuit with an inverter welder.

You can download the millerwelds app for your smartphone or you can use your PC with it here:

Stick Welding Calculator - MillerWelds

Of course the app for your smartphone is more liable to actually be in your pocket in the shop than the PC so you don't need those missing packages

 

[yomax4]

How did that big ole Transformer welder run on a 20 amp breaker?

 

[woodlandfarms]

I have a Everlast 200 stick that is kick butt. The little machine cranks out a lot. I think the frequence and 1GBT makes the welds "hotter" than what it took with my tombstone. I find my settings are 1/3rd less if not 1/2 the amperage from my old Tombstone to the Everlast.

 

[frugalangler]

How did that big ole Transformer welder run on a 20 amp breaker?

That was in a different home, and I ran it w/ a HUGE custom made by a welding vendor extension cord from the Dryer outlet, man that cord was EXPENSIVE (and heavy)!!

Don't have a electric dryer, and if I did it would be even further away LOL. I don't think I'll miss that big box, it has it's place for heavy welding but I don't do that - we actually bought it originally to thaw frozen galvanized water line when it occasionally froze - line from meter to house would sometime choke - had a super long pair of welding leads also, could separate by over 100' end to end - the whole setup cost us less than 2 times having someone come do the job, so it paid for itself in very short order - the cost to 'fix' the issue was way way more than we had economics to do at the time.

I did use it to weld a couple times, light stuff, way to heavy and hard to control, so bought a MIG and never looked at that thing again until now when I need to do some heavier welding than I'm able w/ my small MIG

 

[CADplans]

Even though a welding machine is rated in amps,, it is really using and delivering watts.

Different machines weld at different output voltages, the output voltage is partially controlled by the arc length.
So, welding technique can effect how well a machine can weld.
Short arc length, low voltage,, long arc length, high voltage.
I used to successfully weld with my Miller buzz box plugged into the dryer outlet by keeping the arc length very short.

Occasionally I would forget, and let the arc length go up to 1/8" for 1/8" rod,,,
within 1/2 of a rod, the breaker would trip.

Rather than a long extension cord, I bought long welding cables.

I think they are 75 foot, and 50 foot,,,
usually you can live with a much shorter ground cable.

I have used those same leads on multiple machines for 35 years,,,

SO,, with the right rods,, the right machine, and 20 amps at 220 volts,,,
I would say I could weld 1/2 inch thick steel to 1/2 inch thick steel.

I would not want to do that all day, but, occasionally,, it can be done,,,:thumbsup:

 

[frugalangler]

Even though a welding machine is rated in amps,, it is really using and delivering watts.

Different machines weld at different output voltages, the output voltage is partially controlled by the arc length.
So, welding technique can effect how well a machine can weld.
Short arc length, low voltage,, long arc length, high voltage.
I used to successfully weld with my Miller buzz box plugged into the dryer outlet by keeping the arc length very short.

Occasionally I would forget, and let the arc length go up to 1/8" for 1/8" rod,,,
within 1/2 of a rod, the breaker would trip.

Rather than a long extension cord, I bought long welding cables.

I think they are 75 foot, and 50 foot,,,
usually you can live with a much shorter ground cable.

I have used those same leads on multiple machines for 35 years,,,

SO,, with the right rods,, the right machine, and 20 amps at 220 volts,,,
I would say I could weld 1/2 inch thick steel to 1/2 inch thick steel.

I would not want to do that all day, but, occasionally,, it can be done,,,:thumbsup:

100% agree, only issue is that if the box is 50' away and you need to tweak the settings, that's a pain if it's run out a window or through a door from the dryer outlet location - been there.

My technique is not nearly as good as yours I'm sure, so arc consistency will not be great, but I'm feeling comfortable that an IGBT on a 220V 20A circuit will do what I want to do with some headroom.

 

[Sodo]

My question: What approximate material can this practically weld? I understand duty cycles, etc. but will it be capable of running a 3" long butt weld of 3/16" mild steel?

You're doing the right thing, requesting real world experiential data. I see some pretty wild assumptions on the interwebs. Many wanna advise you to over-buy (like they did). If you get a machine with 20% duty cycle you will NEVER have a duty-cycle problem, in fact you will never even know what it entails. You will have to get your 'duty cyle' problems off the internet (like most).

I've welded 3/16" steel many, many times with about 120v from a 26A generator (Two Honda EU2000i inverter generators, 1600w continuous, "paired" together). 120v x 26.6A = 3200 watts. The generator would have a little trouble at the beginning (not good!) but sped up and would pull 3120 watts steady, no problem. You're not using a generator, you won't have that problem, but the generator does tell you "where it's at" in load capacity. That's all I'm using the generator example for, because you asked about 220v @ 20A.

You have 220v x 20A = 4400 watts. That puts you solidly in the 1/4" + range of steel. And thicker, if you Vee the weld, do multi-pass, etc. Test it with a multimeter you might have 240v (that's 4800w).

I currently have 240v @ 30A so for 220 @ 20A I must refer to my generator experience. Also as a general rule for posting, "I" must always have "more than you", so there you go (I have 30Amps).

So I think we covered it all..... Your 220v@ 20A will work fine.:thumbsup: