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R Scott
Post     Subject: Off-grid welding...?

I just went to an Amish welding shop. They had mig and tig and stick, all running from a welder generator. One engine, a couple add on boxes to run the guns. A couple of the little mig in a suitcase add on boxes will run from batteries.

You need at least a 6k generator to run a 120v mig effectively. Arc start current is pretty heavy. But it can be done for little stuff.
bud smith
Post     Subject: Off-grid welding...?

If energy efficiency is of a prime concern for you then you might want to consider an inverter type welder. They work somewhat differently than the traditional style welders and therefore draw less power for doing the same amount of work.
They are available in both mig and stick style welders.
I have to put out a disclaimer that I have never used one of these but from talking to those that have, they really like these.
http://www.wisegeek.org/what-is-an-inverter-welder.htm
chip sanft
Post     Subject: Off-grid welding...?

Have you thought about oxy-acetylene? I found it a bit trickier in certain respects than stick and TIG but very workable -- actually moreso, because you can cut with it, too. And no electricity needed.
Joseph Lofthouse
Post     Subject: Off-grid welding...?


In that case, diesel generators seem like the way to go... The technology is well established for all sorts of off-grid welding applications.
J Hampshire
Post     Subject: Off-grid welding...?

Joseph Lofthouse wrote:Stick welding with a battery is a well respected, easy to implement, and reliable method of welding. Don't be so quick to blow it off. Battery technology is about 100 years older than The Grid. So I suppose that it's 100 years easier to implement. I could aspire, as a reasonably competent chemist to make a battery based stick-welding apparatus from scratch starting with nothing more than my bare hands and a basic understanding of geology and chemistry. Any old piece of metal wire can be used as an electrode. If I had access to an old automotive junkyard it would be a trivial exercise.

However, TIG or MIG welding requires inert gasses. The availability of those gasses is based on the availability of grid electricity. While it would be possible to make inert nitrogen gas and to compress it without grid power, the process would be very complex. I suppose that it would require reinventing a power grid... Tungsten is a metal that pretty much couldn't be manufactured without a grid, so that's two strikes against TIG welding. So how does one go about making MIG wire without grid power? I suppose that it could be done with pre-grid technology, but it would be sophisticated pre-grid technology, not something that I'd aspire to do on the farm...

The middle ground is to buy a diesel generator, and a huge stockpile of electrodes, and inert gasses, and diesel. Then one could weld off-grid using TIG and MIG until the first necessary input got used up. There are always welding rigs like this available for sale on eBay and Craigslist. They fit in the back of a truck, or on a trailer...



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I specifically mentioned stick as an aside because I'm well-aware of it's capabilities; Having made several similar to the one described in your junk yard soliloquy. My concern lies within specific materials and finishes related to TIG and MIG, which obviously don't run on car batteries. Even if you went nuts with deep cycles, inverters, etc. it's not worth the headache there. As far as gases and their availability are concerned, I'm aware that one "needs a grid" to create those. If my home is off grid but I can acquire items from the grid -- which is most likely never going away in my life time -- then I will bring them to my unconnected property. Same goes for any consumer item. I don't plan on raising dairy cows but I will be drinking milk, sourced from a nearby creamery which has lights, heat and air conditioning from the grid. I simply chose to be off grid for frugality and less-reliance on a larger system.

This was more of an electricity-sourcing question than a welding question.
Joseph Lofthouse
Post     Subject: Off-grid welding...?

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J Hampshire
Post     Subject: Off-grid welding...?

My knowledge in the arena of electricity peaks at light bulb maintenance. I plan to be able to do some rudimentary welding projects in the future. Is anyone welding, totally off the electricity grid? And stick welding doesn't count, I know that can be done anywhere with a battery. I'm specifically interested in TIG and MIG.