ive been a welder fabricator 13 years now and work in birmingham city im thinking of setting up mobile need some expensive kit engine driven mig tig plasma wanna weld alli ss etc any input welcome
you mean a nice fat road tow unit, that does 300 amps plus on MMA, then connect a wire feed unit to it to allow you to MIG. Seen boxes that connect to the weld output that will give you HF tig, from an MMA output. But they only give the out put of the MMA unit, ie if the MMA unit is DC, you get DC tig. Which means you need a weld/gen unit with a good aux output either 240 or 415/3 phase that you can plug a TIG unit into like it was mains, then you can run AC/DC tig. which would mean something like this http://www.diywelding.co.uk/product_details.asp?d=3&c=41&p={D64B3E99-508C-48ED-B358-C81A226AF4D1}
Not cheap but i believe could be outfitted to do what you want. Better still DIYwelding is a member of this forum, so its easy to pick his brains lol
Most of our local mobile welders use a static, screwed to the back of the transit pickup stylee genny. But if you want to do the heavy ally work, it'd got to be a biggy.
Lincoln do a range of mobile genny units that will do everything (but not ac, I notice), here
They have 3 ph 415v, 240v and 110v outputs though, so you can bang an ac tig onto it. Well handy gennys.
I hate to think what they cost though.
If your planning on running all that type of kit on site would it not be best to buy a big 3 phase genny and then a normal MIG,plasma and AC/DC TIG? You would be able to use all the tools in your workshop then take them on site as and when needed.
Buy as big a machine as you can afford..... if you can afford something a bit larger than what you estimate you will need for amperage all the better. I perfer a diesel machine, but that does crank up the price tag. I own a Lincoln Ranger 9 and a Miller Trailblazer, I wish I had stepped up to a 400 amp machine when I bought the Miller something like this unit, http://www.millerwelds.com/products/enginedriven/big_40/. I perfer Miller over Lincoln, but everyone has thier favorite. Miller also makes some plasma cutters with a low input voltage that run very well with their engine drives, I have a spectrum 2050. I have the HF251D Tig unit from miller as well ..... works great. A couple of non voltage sensing heavy duty wire feeders (suitcase style).
The biggest down fall to my Trailblazer is I can only run a small gouging rod and when I'm doing heavy MIG, spray transfer, .045 wire, The machine is running on the upper edge of its performance envelope. It has always performed awesome even when performing the tasks I mentioned, but I hate working a machine about 80 percent of its rated work ability.... I like to ensure that the machine will last a long time, just my take on buying a machine. My machine is a few years older than this one... http://www.millerwelds.com/products/enginedriven/trailblazer_302_diesel/
If this is not a concern to you then something like a Trailblazer would suit you just fine. Actually the TB I linked has a bit more power than mine. Good luck
As Chris said look around for the biggest Welder Generator you can afford I have seen some dc 40-300amps on flea bay they also have 415v sockets and 240v so you can run all your other tools of them, a suitcase type wire feeder and tig unit would give you a wide range but as irondaz said you would only get dc tig.
We use a Mosa Ts300, Its a silenced diesel engined machine, with a 10kva output on 3ph.
You can get tig and mig add ons for them.
The major downside is its size and weight. One man can fairly easily move it about, but it takes two too push it up ramps into a transit.
I don't see why you couldnt build a purpose built low trailer.
Its a mobile unit on a twin wheel frame, and wheel barrow type handles. It does get places where a van wouldnt fit.
With a bit of pipe slipped over the exhaust though, we just run it while its sat in the van whenever possible!