i must agree 150 amp is a suitable machine, it will turn down for materials 1.2 mm and on a high setting is capable for upto 8mm depending on the machines cycle time and the users capability i own a migatronic 160amp mig which i bought over 25 years ago it has`nt missed a beat. things to look out for isthe wire feed rollers as mentioned in a previous post if they are made of plastic or nylon, you will have trouble sooner or later. power settings if it has just hi / low and no power dial to contol the amperage leave alone mainly on smaller machines
turbo migs are equiped with a fan which cools the transformer during use, this lengthens the cycle time(time you can use it before it needs to cool down.) also ensure it has a thermal cut out, should the machine overheat it automatically cuts out and resets when it cools, before it blows afuse or burns out the transformer, nozzle size is another thing to look out for a large shroud mb15 with 6mm threaded tips is less likely to clog up with splatter un like the smaller hobby mig type.
ive welded everything and anything over the years, from car bodies to roll cages, wrought iron gates to home made trailers the only things ive replaced are tips, shrouds, 2 teflon torch liners. 1 tip holder and spring. i fitted a new earth clamp and fitted a fan from an air conditioning unit to the inside panel to turn it i into a `turbo mig` not bad for the age of the machine .
i run it on CO2 gas which is classed as MAG welding not MIG welding the weld is not as clean as mig which is CO2 and argon mixed gases. but the majority is covered by paint or underseal so it doesnt matter plus CO2 is cheaper to buy (its the same gas as they use in pubs to pressurise the beer barrels. its worth spending on a machine that lasts, i first started with a S I P 100amp hobbymig. great for the experience, brill for car bodywork, but i found 4mm or above and i couldnt get penetration in the weld, so i part ex`ed it for my migatronic, best thing i everdone, ive saved a fortune over the years. sorry to waffle on a bit, i hope this can be of help to you Andy