To MIG or not to MIG

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Bought one of the Swag Off Road bending brake kits to fit the HF 20T hydraulic press.  It is mainly just parts and requires some welding and grinding to assemble.Basically two guide posts, 7/8" in dia. must be welded to the 1/4" bottom support plate after they have been pressed into precut holes, 1-1/2" x 3/16" angle then welded to the support plate forming the lower "die", and two 1-3/8" x 3" round tubes ( 3/16" wall) welded parallel to the ends of the 1/2" upper die.  I have an 225 amp DC arc welder but would like to use my HH190 to stick all this together.  I am not worried about the lower die/support plate welds but I am not sure if it would handle welding tube to 1/2" plate or 7/8" rod to 1/4" plate.  Otherwise I can just glom it all together with the arc welder using 7018 or 6011 but it wouldn't look as pretty.I have 200 amp TIG as well but it isn't my best skill.  Neither of the heavy thickness welds carry any real load per se, they are just guides so I don't need a huge amount of penetration.  The guide rods are a tight pressed fit and essentially just need to be secured but Any comments?Steve in Central TX
Reply:Hi , you might post this on the Hobart site where a knowledgeable person could respond on that machine. http://www.hobartwelders.com/weldtalk/
Reply:The Hobart at max output would be barely adequate. 7018 beads look pretty to me. JohnA few weldersA lot of hammersA whole lot of C-clamps
Reply:Hi Steve.As a general rule you should not MIG weld materials thicker than 1/8" or 3mm, unless your welding machine has 250 amps or more. Side note: Also whatever you do, you should ignore manufacturers claims to the contrary. The rule of 1 amp per 0.001" does NOT apply to MIG! But a lot of so-called "weld engineers' don't know that.Anyway If something needs to be done it deserves to be done right, says me. You can use the MIG for tacking things up which is easier. But if I were you I'd use 7018 to weld the thing.20 tons is a lot of force. Imagine stacking a fully loaded concrete truck on top of the thing.