powering mig with portable generator

I usually avoid jobs that require welding outside of my shop. However I am bidding some work that will require some degree of "on site" welding.

I really don't want to go with an engine driven stick machine. My thoughts are to buy a portable generator and use it to power a Lincoln WireMatic 250 that I already own. I could leave the tank and mig lead at home and use the spoolgun with 035 or 045 flux core. The welding will be outdoors.

Has anyone tried this and care to share the results? How large must the generator be?

BTW - I need a new standby generator for power outages at home. This could kill two birds with one stone.

Thanks for any advise, SCOTTIE

You will need a machine 10Kw plus. Look for something like an Onan or Kohler based 2 cylinder. Around 18HP.

Why not just rent an engine drive for the job?

I would still use gas. just use a couple sheets of plywood for wind breaks. It will save you loads of time in cleanup.

When you say spool gun, is this because your using aluminum, stainless, etc..? The reason I ask, is I keep a junk/off brand wire welder for situations like this.

I presently use a similar setup for emergency small repairs to handrails and conex boxes except the machine is a Millermatic 135 and a 3500W generator.

It works really well with the flux core. Saves lugging the bottle around. Cleanup is easy. If settings are correct the flux pretty much falls off.

This latest project is going to require a little more uuummp.

The spoolgun gives me more flexibility and more reach from the truck. The welds will not be extensive so the 2 pounders will be fine. (I already have the spoolgun and sometimes use it with steel wire.)

Has anyone here run a 250 amp machine on a portable generator?

ran a miller 210 off a 8500 watt home owner special for a day and 1/2. i think we had the miller on 3 (1 to 5) power range. .035 wire with 75/25 and no welds more than 3" at a time. the equipment was not mine and i suggested a portable welding unit for the job. a cheaply run deal at the time and me the trigger man on the glue gun had no say. turns out the job payed good because of remote location and nothing was fried

Hey SCOTTIE,
I use a generator on my welding trailer to power all my equipment. It is a 7.5kw continuous/8.75kw surge. I can run any of my welders or other power tools with the compressor running. Ok, now here's why... all my welders are full inverter welders and only draw 23.5A max for any one of them, & the plasma will draw 33A but won't operate when the air pressure drops below 70psi, & the compressor is set up to kick on at 65psi, so there is no conflict. Even so, the surge wattage of the gen. could handle the startup of the compressor if the plasma was engaged. I picked up the generator from an estate sale for $350 w/elec. start & only had 1 hr of run time on it....like new. Been using it for all my mobile welding for 3 years now and it's been like the Energizer Bunny.

1) What is the input amperage requirement of your Lincoln at full output?
2) How heavy(thick) material do you think you are going to encounter?
3) Are you going to have anything else running(compressor, grinder, lights) while welding?

I have another generator exactly the same in my basement I use to provide power to my entire home when there is an outage and I have not had any issue at all with it. I would suggest, as others indicated, a 10kw+ unit would always be better, since I believe your Lincoln has a much heavier input draw than a full inverter. Your only other recourse would be to consider a smaller welder such as a 150-200A unit that would have a lower input requirement. Again, this would depend on the parameters of your field welding. You can do a daily check on Craigslist for a good used unit that would fill your needs(both a gen & lower power MIG), and with the economy as it is, there are some really good deals out there. Anyway, hope this gives you some food-for-thought. Denny

I use my Miler bobcat to power my Milermatic 200 which is a 250a transformer machine. The generator is 10Kw IIRC, hardly what I would consider portable. It handles the welder well. Now having said that I do a lot of outside welding. If you are going to use flux core then I see no reason not to use SMAW. MIG is just too susceptible to wind etc. and SMAW really works well in the weather. Of course I have no idea as to the pertinent details of your job.

Before I owned my Lincoln Ranger 250 portable welder, I once used a portable generator to power my Lincoln Square Wave TIG to fix a Ford 555 backhoe/loader in the middle of a field. I had the welding machine in stick mode for a bucket repair. Sorry, I don't remember too much about the generator other than it was V-Twin powered and my Lincoln plugged right into it (220V, 50A plug).

I have also used the Ranger 250 (18 HP, V-Twin Kohler, 9500 Amp generator) to power my Lincoln Power MIG 215 and the Square Wave TIG for portable work.