Need advise, MIG welding technique

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I'm self taught. I've never welded with any machine for the last 6 years other than a miller 135 and then a 09 140 millermatic. Last month, i bought a Lincoln Power Mig 216 to replace the MM140.I build art and furniture. Peoples lives are not at risk if one of my welds fails. My work is cleaned and clear coated with the welds fully exposed for people to see, kind of an industrial look. Actually, the photos below show a piece that will eventually be powder coated a color and the welds will be covered over. I had a camera with me and ive been wanting to ask this question for a while so i snapped some photos today.I really want to build good quality work. The general public, which i build for, has no idea a good weld from a bad weld. They dont know push or pull ETC. When my work gets viewed by an educated and trained welder, I would like for them to say to themselves ... "thats pretty damn good."Its been 5-6 years since i started welding. Ive pretty much, from day one, watched my puddle while MIG welding by pulling the weld puddle and also stop-started the arc. I am not holding the trigger continuously. I can, and do, push the weld with the same results as the photos show below. Im still stop-starting the trigger.Can I get some honest and no sugar coated opinion on what im doing? Like a golfer who needs to re-tool his swing, do i need to abandon this method? Do I need to force myself to push-the-weld puddle with a continuous weld until im get comfortable and can acheive a pretty weld bead ? Does anyone know someone in Arizona who is a brilliant MIG welder who I could reach out to for some $ training? Im not too proud to ask for advise or assistance. My goal is to be a better welder and i feel that my own knowledge has plateaued. Sorry for the pictures, i could not get good focus so close up.Sincerely, Joel
Reply:to me the aesthetics of what you are doing are good..not sure what you are striving for..technically yer technique (start-stop)  is probably terrible for anything structural but if its furniture and art why change it?if you want tobe a better mig welder, theres good help on this forum..i dont wirefeed much but someone will come along..
Reply:Hey Joel,Personally, I find a continuous "push" method & a smooth weld bead, with good penetration, to be the optimum result. I do some "pull" method in odd configurations, inside corners, & if I need a bit more penetration. That so called, "TIG look", really means nothing when a good structural, strong weldment is necessary.......even for furniture. Your beads indicate some porosity as there are pinholes evident. I would suggest to learn to just do a continuous, non-stop bead. Do some practice pieces, do a bend test, cut a few & examine the penetration, & evaluate the result. At my age(67) I can only go continuously for about 12" before my wrists need a break. A good, solid, interrupted bead is as aesthetically pleasant as a "stack-o-dime" look, & probably better.DennyComplete Welding/Machine/Fab. ShopMobile UnitFinally retired*Moderator*"A man's word is his honor...without honor there is nothing.""Words are like bullets.... Once they leave your muzzle, you cannot get them back."
Reply:As far as aesthetics go, I'd say that looks damn good.  Its impressive that you can get such a smooth and consistant look with stopping and starting so much.  As someone mentioned earlier, your penetration may be an issue.
Reply:One thing to keep in mind.Full penetration welds on stainless runs the risk of distortion.  Your pulsing technique almost certainly limits this.But if you want to experiment... there is a video on  weldingtipsandtricks talking about making little cursive 'e' or 'l' as you move.  Gives a similar look.There is a thread here titled "MIG like TIG" with some other images of the same technique.Good luckCon Fuse!Miller Dynasty 350Millermatic 350P-Spoolmatic 30AMiller Multimatic 200Hypertherm PowerMax 1000G3Miller Maxstar 200DX
Reply:Originally Posted by yorkiepapHey Joel,Personally, I find a continuous "push" method & a smooth weld bead, with good penetration, to be the optimum result. I do some "pull" method in odd configurations, inside corners, & if I need a bit more penetration. That so called, "TIG look", really means nothing when a good structural, strong weldment is necessary.......even for furniture. Your beads indicate some porosity as there are pinholes evident. I would suggest to learn to just do a continuous, non-stop bead. Do some practice pieces, do a bend test, cut a few & examine the penetration, & evaluate the result. At my age(67) I can only go continuously for about 12" before my wrists need a break. A good, solid, interrupted bead is as aesthetically pleasant as a "stack-o-dime" look, & probably better.Denny
Reply:They are uniformly flawed. The center crater is a weak point. If you stay with that appearance as a goal, try running them without pulsing the trigger. That will help reduce the center cratering.A smooth bead is also a great technique to learn.City of L.A. Structural; Manual & Semi-Automatic;"Surely there is a mine for silver, and a place where gold is refined. Iron is taken from the earth, and copper is smelted from ore."Job 28:1,2Lincoln, Miller, Victor & ISV BibleDanny
Reply:I was taught the cursive e technique first and have it memory locked as instinctive as breathing.  There is nothing inherently wrong with the cursive e, but I would also strive for learning all the other sound techniques.  The technique you have is terribly wrong.Here is the reason it is wrong.  First, the inherent flaw with mig welding is the cold start.  The startup of a mig weld is an area that tends to be the cause of a failed weld due to lack of fusion. Second, the second flaw is the crater caused by incomplete filler metal filling.  This is the second area that causes failures.  Third and lastly, is penetration.  this technique yeilds no penetration.  All you have in your weld is repeated cold starts, craters and lack of penetration and fusion.If you look at the leg that is vertical where you have ground the weld off.  you can see the dotted spots on either side of the ground down weld bead where there is lack of fusion.  That is under every bead.  only can't see it due to cold lap. Attached ImagesLast edited by Scott Young; 08-01-2011 at 03:21 AM.
Reply:I saw this just as i was proof reading my last post. Attached Images
Reply:Their are some that will fight you over the belief that the tig look is structurally sound but rather than repeat all yorkie said go with a smooth push bead, as all you have is good mig equipment, if you like the tig look then maybe go with tig, need production then go with tig feeder, and you will get that respect.
Reply:Originally Posted by Scott YoungI saw this just as i was proof reading my last post.
Reply:yep that was what i saw too.
Reply:I know this does not really answer your question, but if you are going for that TIG look, why not just weld it up using the TIG process? It resolves the issues that your existing welds have that were mentioned by others here, and will still allow you to have that look you are going for.Yeah, there is going to be a learning curve, but once you get it, you are going to love the results. Compared to the procedure you are using now, TIG will not be any slower. You could get a brand new miller diversion 165 which is all you would need and not spend more than 1300-1400 dollars.If you are set on sticking with MIG and getting the look you are getting now, the main thing I'd change is to stack your tacks a little closer to cover that little crater you see, and maybe when you do each tack, start a little ahead of where the previous tack was and then come back to it. That will help a little with the cold start problem mentioned by others here.Can we see some pictures of your completed works?Good luck,RussMiller 302GMIller 12RC SuitecaseMIller 30A spoolgunHF-251D-1WP17 Tig torchSmith HD torchHypertherm 45Jet drill pressHF 7X12 wet cut horizontal band sawPlasmacam CNC table
Reply:Thanks everyone for their replies. I do have a TIG machine, its listed in my signature.As for the areas that were circled, i believe they are not related to the welding technique. The area above the welded joint was one of a series of 1 inch long tac welds placed there in specific areas to hold the 2 pieces of tubing together while i cut it. The tac weld was a quick back and fourth motion between the two tubes and when ground down, youre seeing area that were not welded. Same goes for the miter joint, the saw made a descent gap to be filled by cutting a 2x4 inch tube on a milwaukee dry cut saw. But just to be sure, i will grind down a stop-start weld tomorrow and see what is under there. When welding this way, the area that gets hit again with a new weld is still red hot and they seem to flow together nicely, giving a concave appearance. As opposed to a bead that is obviously cold.Welding 16 and 14 ga tubing can't take tons of heat, especially on miter cuts where there is a descent gap from shltty cutting. Erroring on the side of too much heat means you'll burn right through it. So the E method has always either burned through this type of 45* butt weld or they are too cold. Maybe i'll TIG these joints after i get my scotchman cold saw when the joints are perfect.Thanks for the input. Not sure im going to find my answer online but rather getting some time with someone in person.Thanks allLast edited by Jimmy_pop; 08-01-2011 at 10:29 AM.
Reply:Originally Posted by Jimmy_popThanks everyone for their replies. I do have a TIG machine, its listed in my signature.As for the areas that were circled, i believe they are not related to the welding technique. The area above the welded joint was one of a series of 1 inch long tac welds placed there in specific areas to hold the 2 pieces of tubing together while i cut it. The tac weld was a quick back and fourth motion between the two tubes and when ground down, youre seeing area that were not welded. Same goes for the miter joint, the saw made a descent gap to be filled by cutting a 2x4 inch tube on a milwaukee dry cut saw. But just to be sure, i will grind down a stop-start weld tomorrow and see what is under there. When welding this way, the area that gets hit again with a new weld is still red hot and they seem to flow together nicely, giving a concave appearance. As opposed to a bead that is obviously cold.Welding 16 and 14 ga tubing can't take tons of heat, especially on miter cuts where there is a descent gap from shltty cutting. Erroring on the side of too much heat means you'll burn right through it. So the E method has always either burned through this type of 45* butt weld or they are too cold. Maybe i'll TIG these joints after i get my scotchman cold saw when the joints are perfect.Thanks for the input. Not sure im going to find my answer online but rather getting some time with someone in person.Thanks all