Using generator for welder

[arkydog]

I have to weld a winch at a remote location and the generator is a coleman 4000 watt (16.6 amp at 240 volts). The lincoln welder is A/C, DC. What is the highest setting I can safely use on the DC side for the 16.5 amp from the generator and what size diameter rod (probably 6013 or 6011) to weld 1/4" mild steel.

Is there a formula for figuring what the DC amp setting should be for the amp input from the generator?

Thanks!

arkydog

 

[bobodu]

That doesn't sound like a happy combination to me /forums/images/graemlins/frown.gif
I have a little 220v welder than I run a 30a breaker on just for the light stuff like 11 gauge.I pop the breaker quite a bit at 100 a.Anything else and I'll drag out the Lincoln 225 and it runs a 50a breaker.Not an expert by any means but I'd be suprised if you can run 50 a at the welder without blowing the breaker on the genset.

 

[ronjhall]

You should be able to run over 400 amps with your generator. Most AC welders use around 30 volts AC for welding voltage.
When using a generator to run a welder. I have had trouble getting a arc started. If you have auto idle on your generator turn it off. It may help.

 

[rockinmywaypa]

A few years ago at a previous job we had to install a barn cleaner chute before the hydro was installed. Superviser rented a 6500 watt generater for the welder. Long story short it was teribly undersized, couldn't run a bead more than 1/2 inch and breaker would blow. Took hours longer just to get supports in place enough to hold till hydro was put in and proper job could be done. I'd say forget the 4000.

 

[PILOON]

My first homemade welder was a 24volt 25 amp transformer that had a 115ac input.
I found that I could weld 1/4" stock if I used 1/16 or 3/32 6013 rod and more passes.
Striking an ark was tricky due to the lower voltage but it did the job.
I needed to use a 25 amp slo blo fuse.

The hammond is HD industrial transformer so it stood up quite well for many years until I could afford a real buzz box.

Fixed many a kids bike and stuff and developped techniques that were fine tuned for when I had a real welder.

The main problem was sticking rods (and blown fuses) due to low voltage but otherwise it performed quite OK.

ps: I still , sometimes use that old setup rather than tote the buzz box to the job for the odd little 'tacking job'

<font color="blue"> formula:watts=volts X amps </font>


Most welders will have an open circuit voltage of 70 or so volts.

4000watts/70 volts=57amps
So, in theory, you could weld with a rod that uses less than 57 amps.

Check the rod amperage tables to find a matching rod.

Off of the top of my head, I suspect 3/32" 6013 is OK but then you'd have to make a few passes.
I think 1/8 rod would draw too much current.

Basically, use your welder on 240 and try it with small rods that draw less than 60 amps.
The worst that'l happen is you will pop the generator breakers if you draw too much current.

 

[mrcaptainbob]

My 6500W, 30A generator runs my Hobart mig okay, and it does manage my son's giant Lincoln, but we've never done anything over 3/16. The generatot is taxed when running my son's mig.

 

[ZJ_HR]

Biggest problem for using welders on gensets is big reactive power. 4000W will be enough for welding with 120-150Amps (120-150 x 25V arc voltage), but problem is that transformer "sucks" more, as you calculated, and will drop generator voltage.
You can solve a problem by connecting capacitor from single phase motor (up to 200uF/400V) in paralell with welder to decrease inductive current /forums/images/graemlins/wink.gif

If you have MIG welder, use it, as it works better on gensets (different transformer characteristics) or lease an inverter rod welder.

 

[pat32rf]

Don't know about the DC part of it but I use a 4.5KW Onan to power my 225 Lincoln all the time, I just use 3/32 rods such as 6013, 7018 and make multiple passes. If the gen breaker trips you let it cool and take shorter passes. I do believe though that a 4kw Coleman is a little light for your job. Any chance of renting/borrowing a bigger unit, or take lots of breaks while welding?

 

[arkydog]

Thanks for all the replys! The winch is on a boat dock with access by 4 wheel drive only and there is no electricity, only generators. I tried my 110 Lincoln mig, but with the wind and breeze its just too hard to get a good weld, even built shelter around but deck boards have too much space between them. Thats why I have to use a stick welder.

I dont want to borrow someones generator because of the chance of breaking or damaging it, just dont like to borrow tools. I have always said you break it, you bought it!

Hopefully only popping the breaker is the only damage I will do to my generator.

Thanks

arkydog

 

[1962]

i am an iron worker by trade. your best bet would be to rent a larger generator, rental units are pretty rugged and a couple extra bucks for rental insurance would protect you from any breakage(should any occur). the 4000 watt coleman is a little light. if you rent the larger unit, use a 1/8 7014 rod. if you must use the 4000 w machine, try a 3/32 7014 rod,it's a fast deposit rod, and maintains a stable, easy start arc....

 

[horseman1]

Arky,

Maybe I missed this, but could you use flux core wire on your Lincoln wire feeder and get a decent weld outside with a little breeze?

Kurt

 

[arkydog]

I dont know a great deal about arc welding (built my own backhoe with stick welder), but I never had much luck welding 1/4" steel with a 110 mig welder. I once had a century 110 wdelder that I put flux core wire on and didnt have much luck welding 3/16" plate with it. It didnt get as much penetration that I was happy with.

My thinking is with the dc rod and welder, run by the 4000 watt generator that I could get away with it and get a better weld that way.

The renting of the portable welder at this time doesnt appear to be an option considering the location and accesibility to the winch. Pulling the winch out to work on it is the last option because it is a day to remove and a day to reinstall.

It should only take about 2-3 hours to repair the winch either on the dock or at the shop. Thats why I'm hoping that I can find a solution to repair it on the dock.

Thanks

arkydog

 

[1962]

arky,
give it a practice run at home. try a 3/32 or 7014 rod.you can use these on dc if you like,the 6010 rod is dc only. try a comparable size of scrap steel, pick a low amp setting and start your arc. you can use a 6011 ac rod for deeper penetration but it's a little less stable and can't use the drag method. the reason i was leaning more towrd the 7014 rod is it's heavy iron coating,very smoth to weld with..rick

 

[bobodu]

How fast can you learn to weld with gas?
I really suggest that you try this genset out at home before to waste your time and find that all you can do is tackweld before the breaker pops.A 16 amp power supply ain't didly in the welding world.
You can gets tons more suggestions here
Machine Builders Network
Pose your question in the Welding area.

 

[andyfletcher]

You can also use a WW2 air craft generator HAS a welder. These
generators can develop 300 amps without any problems and can be used directly. Back in the 60's these were common and usually powered by a 4 cylinder air cooled Wisconsin or small auto engine.

You may still find these generators at surplus military outlets.

 

[arkydog]

With the military surplus generator, is there any way to control the output for various welding voltages?

Thanks

arkydog

 

[Highbeam]

You can get way more amps out of the arc welder running on AC. I have run nice big beads with 1/8" 7018 and 200 amps on grouser pads with my coleman 6250 watt generator and lincoln 225 AC welder. This is a great cheap portable welder package.

The fuses on generators are a slow trip deal so the high striking power won't blow the breaker. It will be the long steady arc at high amps that does you in.

25 volts while welding AC means your 100 amp setting is burning up 2500 watts plus a little for inefficiency. 100 amps will allow a decent weld with 3/32 rod on 1/4" plate using more than one pass. If the winch needs to be temporarily fixed to get you out of a jamb, then use what you've got.