hello

I got an ESAB Origo Mig c250 3ph (http://www.esab.com/gb/en/support/upload/Origo-Mig-C170-3ph-C200-3ph-C250-3ph.pdf).

by looking at the specs in the user manual could you tell me about it's capabilities? is it just for light fabrication use or I can use it for welding the heavy pieces of an DIY power hammer (18cm diameter anvil to 5cm thick baseplate, for example), as it's an upcoming project?

Nice machine.  Similar to my millermatic 251 which I was using not 5 minutes ago.

On the inside of the spool cover the millermatic has a chart of recommended settings for metal thicknesses and wire diameters.  Does yours?  That chart on the 251 goes up to 1/2" but I'd say 3/8" is more realistic in terms of day in and out.  Since the Millermatic and ESAB are rated about the same output, I'd say the capabilities are similar too.

I prefer welding with gas--an argon CO2 mix for carbon steels.  I never liked the flux cored wires.  Some people love them and hate paying for gas so I guess it's just a matter of taste.  

For wire diameter, choose something common and in the middle.  In the USA that's usually about .035" or .889 mm.  It'd be good on small to medium work and you could push it to larger work here and there.

If you can get to spray transfer mode (look that up, too complicated to explain here) it's like the welder will suddenly become far more stable and produce the prettiest welds you have ever seen.

What do you consider heavy pieces?  That machine will do some nice fabrication but if you are talking about welding 50 mm thick blocks, you probably want to do that with a stick machine anyway.  Too slow with a MIG and not enough heat input.  Basic stick machines are cheap as dirt.  You probably want one around anyway.  

It is not a heavy industrial grade machine, the duty cycle is too low (35%) with large diameter wires. It is meant for light industrial use or in a home shop on sheet metal or light plate 0,6mm - 6,0mm.

With solid wire in the short circuit transfer mode, single pass welding is limited to 6mm, or about 1/4" thickness, but it should be be more than capable of multi-pass welding of thicker plates with adequate pre-heat. It is also capable of self-shielded flux core welding, which is a stronger, but messier process.

If you have access to the maximum 3 phase power for this machine, it should even be capable of spray arc transfer with solid wire. As noted above, too difficult to convey in words.

thank you guys! now I have yo learn the machine... and the craft.