Mig, question on butt joints and tubing outside corners

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Ok so I have zero issues with fillet and lap joints at this point with MIG. All thats bugging me now is my butt joints and outside corners.As far as butt joints go, is there any particular technique that will result in a flatter bead profile? I've tried the small circles/Es (my usual go to method for everything) and just running in a straight push or pull and none seem to result in a truly  nice weld like my fillets come out. How do you guys usually go about it? I also find it very hard to do a pulling movement on butt joints because I can't see where the end of my bead needs to stop is any tips there?As far as the corners go, I have no problem with plate outside corners they come out fine. My grudge is with corners made by putting two pieces of tubing together and fusing together the sharp corner. It always just looks like I slapped a small slug on the edge of the corner and forces me to grind the corner smooth again because it just looks so out of place.Realistically I imagine the answer to both of these questions is to tig weld it yet, but I can barely do a bead without dipping the tungsten right now as far as my tig experience goes and I am not looking to practice on a legitimate project.Last edited by BrooklynBravest; 10-03-2014 at 08:43 PM.www.FirehouseFabricators.comZachLincoln 210mpLincoln SW200Hypertherm Powermax 45xp2x4 CNC Plasma Table.
Reply:Bevel?Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:Gas blend?Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:Position?Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:Wire size and alloy?Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:Originally Posted by shovelonBevel?
Reply:BrooklynBravestJoinery.If you don't have this book - get it:The Procedure Handbook of Arc Welding - by Lincoln Electric.If you have it - read, and review ad nauseum.Fine metal work is preparation - Welding is the frosting.Opus
Reply:Sorry I'm welding in the flat positionC25 030 wireNo bevel but I was thinking I should it only makes sense that it would eat up some of the metal I lay down.
Reply:I've done lots of miter joints on 1 1/2"x ,065" wall sq tube and found it works best to "tig" w/ the mig by manually pulsing the weld on the outside part.                                                   MikeOl' Stonebreaker  "Experience is the name everyone gives to their mistakes"Hobart G-213 portableMiller 175 migMiller thunderbolt ac/dc stick Victor O/A setupMakita chop saw
Reply:Well you could go with a bevel, C10 gas to push the arc to spray, and go downhill. .025 wire might help push into spray as well. Personally I like .030. Esab/Allstate easygrind .030 flows like butter. I also run Metaloy Vantage metalcore wire with C10 for strength with outstanding results but is is costly.Weld like a "WELDOR", not a wel-"DERR" MillerDynasty700DX,Dynasty350DX4ea,Dynasty200DX,Li  ncolnSW200-2ea.,MillerMatic350P,MillerMatic200w/spoolgun,MKCobraMig260,Lincoln SP-170T,PlasmaCam/Hypertherm1250,HFProTig2ea,MigMax1ea.
Reply:As awesome as those suggestions sound, I'm just a guy in his one car garage. c10 isn't gonna be in the budget.Woukd a decent bevel alone help much?
Reply:A bevel will give the filler metal somewhere to go so it doesn't pile up so much.GravelThe difference between theory and practice is that in theory there is no difference.
Reply:Back to this topic...How in the world do I make these stupid outside corners weld cleanly? No matter what I do it ends up a non uniform shape or a nasty slug all together. Almost want to just fuse them together with TIG and call it a day.Just to clarify, I am talking about the vertical edge opposite the fillet weld formed when mitering two tubes together such as this picture(not my work just an example)Last edited by BrooklynBravest; 11-30-2014 at 10:32 PM.www.FirehouseFabricators.comZachLincoln 210mpLincoln SW200Hypertherm Powermax 45xp2x4 CNC Plasma Table.
Reply:Outside corners when they are mitered like this are almost always a knife edge that's a pain to weld. You have 2 choices. #1 grind the corners back to full thickness material which can often leave a large gap to fill, or #2 cut the miters "short" of the corner, leaving full thickness at the ends and creating a bevel that needs to be filled. In effect when you do this it's just as if you had made the piece slightly longer and ground back the knife edges like in #1.I know I did a post for some one else a while back with drawings to show this, but I can't locate it right now..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:Are you pushing or pulling the weld? Pushing and a little more volts will flatten the bead. Another thing you could do is have a slight gap to lessen build up but you have to be more careful. On thinner material a gap will be about the same as a bevel.
Reply:On the thin stuff I'll grind them flat like DSW says in post #14, then depending on the tube size/dimension and gap (if any) I'll shoot a couple of tacks in there to keep it from opening up or dropping out when you run your bead. So for a 1 &1/2 tube I'd put about three tacks in the center area, grind those back down to about nuttin, then make a run for it. A vertical down works sometimes too along with the prep."The things that will destroy America are prosperity at any price, peace at any price, safety first instead of duty first, the love of soft living and the get rich quick theory of life." -Theodore Roosevelt
Reply:If that is 16 ga, run them downhill.If it were thicker, prop one end of the work up, so it is only semi-downhill,say a 45. Experiment to find the optimum angle.As suggested, flatten the sharp corner, for sure.Last edited by geezerbill; 12-01-2014 at 10:12 AM.Hobart Beta-Mig 2511972 Miller AEAD-200LEMiller 250 TwinNorthern Ind. Hybrid 200Longevity Stick 140Longevity Migweld 200SThermal Arc Pak 3XR
Reply:You guys use same settings for downhill as you would flat?www.FirehouseFabricators.comZachLincoln 210mpLincoln SW200Hypertherm Powermax 45xp2x4 CNC Plasma Table.
Reply:Mig is a deceiving process, your flat welds and t joint can look beautiful, but when it goes to down hill and UN-beveled butt welds it will show its flaws, crank the heat and watch the puddle. For down hill and butt welds we would use the same settings for metal 1/8in up in thickness. So for example on 1/8th in material with butt welds and downhill welds, such as the stall door in the pictures, we would weld it on the same settings for a flat t-joint on 1/4in. Attached Images
Reply:Give yourself a gap to fill and let it flow in, if it key holes really bad/blow through, turn the welder down and move side to side. If you have a gap, and by gap I mean 1/16 to 1/8" a weave motion will allow the metal to lay in nice and less grinding. If you have a gap the settings stay the same, if you are metal bound and flat, try to get as much voltage as you can and still maintain an arc, you will still get a tall weld.2x2x3/16 45* miter joint with almost 1/4" gap on the outside I welded yesterday, vertical down, never let off the trigger, just side to side, float and fill. Watch the outside of the puddle to wash in while the other side cools.14' PowerMig 210 MP13'Burntables 5x10 CNC Table14' SAE300 HE on a 12' Ram 4500 60 CA 4x4. Custom bed/bottles/reels.87' SA250d, 78 SA200,11' Ranger 250 GXT AC/DCThermal Dynamics Cutmaster 8112' Lincoln Precision Tig 22508' LN25