Electrode selection for 4" square bar

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I'm putting together a 2 shank ripper for pulling tree stumps.  The frame is made of 4" solid mild steel bar.  Can anyone give me some suggestions on what types of electrode and what size I should use.  I'll be using my Miller 330A/BP.Strength is critical.  Thanks.
Reply:You are welding 4" thick solid bar together? Wow, that's gonna take a bunch of beveling and a few pounds of big rods in several passes. Which rod you choose isn't gonna matter near as much as how well  you prep the joint.Miller EconotigCutmaster 38Yes ma'am, that IS a screwdriver in my pocket!
Reply:4" of weld isn't really enough to make a rod like 7024 pay, so I'd go with 1/8 or 5/32 7018, probably root with 1/8, and fill with 5/32. Might even be able to get away with 3/16 for fill.In my opinion, 6010 (or 6011) don't let you get metal in fast enough to avoid frustration on something like this.Once you get a root in, you can widen the weave until you are laying in a pad of stringers across the joint. Fills fast this way, but watch for distortion.
Reply:A few folks have suggested 7018 in the 3/16th diameter.  I'm no pro but why wouldn't I run the first pass with 6011 for the best penetration?
Reply:Are you welding the 4" bar to something or butt welding 2 ends of 4 " bar together?
Reply:Just start with 1/8 7018 and work your way up.What kind of joint do you have?DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:I have 2 different joints.  The first is the 4" square bar that Ts into another 4" square bar.  The second type is the shanks welded to the square bar.  The shanks are fabricated from 1" x 8" flat bar.My plan is to weld the joints then overlap them with more flat bar.  Let me know if I'm on the right track.  Thanks.
Reply:At #1, I would cult, gouge, or grind a VEE on the right piece, top and bottom. Weld those so its solid. Weld the fillets verticle up with 1/8" 7018 maybe a 3/4" fillet.   It sounds like you should weld it solid.  If you do all that, it won't break   Yeah, you are on the right track.DavidReal world weldin.  When I grow up I want to be a tig weldor.