MIG Weave Vs No Weave

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At work, a supposed "tradesman" told me that doing the weave was a bad idea, because it revealed cold spots in the weld pool, and that there is more of a chance of the weld cracking, then i was told by a different tradesman, who happeend to know a fair bit about welding, and he said that doign the weave eliminates air pockets and provides a stronger, cleaner and better looking weld then without the weave. Yesterday at work i had to weld for almost 4 hours, i was just told to practise my welding, although i can alredy weld pretty good (Ill get some pics), and i showed my supervisor the welds i did, and he agreed that the weaved ones looked 100% better then the non-weave welds.The settings i applied to the welder were 185Amps, ++++, 0.9 carbon steel wire, #447 Soft Arc, Gas: Argon +5% Co2 + 2% 02. The welder is a  WIA Synchro Pulse CDT 450, and i was welding 6mm Mild steel plate."EDIT" I just thought i would say, that with the weave, for people who dont know what im talkign about or if i havent worded it properly, basically, you weld 10mm then go back 5mm, weld 10mm then go back 5, so that the weld looks much like a fish scale or snake skin....So what i would like to know is, what is the better soloution, and if the weave is acceptable on all types of metal, such as stainless, aluminium or titanium?Is it also acceptable when doing specialist welding, like on pressure vessels or hardfacing, or where tickets would be required to complete, let alone even touch the job with a welder?Any help is greatly appreciated......Weazy Out....Last edited by Weazy; 11-15-2006 at 04:16 PM."One World...One Muay Thai...Muay Thai Never Dies..."
Reply:I prefer not to weave unless I'm welding a big gap. I just like the smooth shiny look better. But, I think it is a matter of what works best for you. If your welds look better with a weave then, by all means, keep it up.     I weld on steel only at work so for the other metals I can't help you.
Reply:"EDIT" I just thought i would say, that with the weave, for people who dont know what im talkign about or if i havent worded it properly, basically, you weld 10mm then go back 5mm, weld 10mm then go back 5, so that the weld looks much like a fish scale or snake skin....
Reply:One of the problems with both weaving and whipping ('whip and pause') is that they tend to cause more distortion than running straight stringers.Distortion is mostly a function of heat input. Heat input is a function of voltage, amperage, and travel speed (this applies to all fusion welding processes). Assuming you keep the voltage and amperage the same, the slower overall travel speed caused by whipping/weaving will cause more heat input and thus distortion.While it is usually easier to make a prettier weave/whip bead it is more difficult to get as much penetration as with a stringer bread. More heat into the joint does not necessarily equal more penetration, especially with MIG. A good weld will always be pretty, but a pretty weld is not always a good weld.As far as when the second tradesman told you that weaving "eliminates air pockets," If there were any actual air anywhere near the weld puddle during welding you would get instant porosity due to the oxygen (and other harmful gasses) in the air. If he was actually talking about getting rid of voids or lack of fusion between beads he would only be right if, and only if, the weaving were done correctly (see previous paragraph).Furthermore, many codes disallow the use of weaving for all of the above reasons.If I were you, I'd get good at making quality welds with both techniques (use destructive testing as much as possible, particularly macro-etching). Use the weave where cosmetics is more important than strength and use stringers if somebody's life and/or safety depend on getting a sound weld.Visit Tensaiteki.com
Reply:Let´s see....I like weaving, but no 10 mm front 5 mm back...that´s a lot of wasted heat...I do from top to bottom...having a nice time rest on the middle so penetration can be achieved....this is what it looks like at the end....weaving motion is from tube to plate...from plate to tube...from tube to plate...and going forward (in the pic, forward is to the left)....I´ve never tried 10 mm and 5 mm...I think that would just make a big plast of metal. Attached ImagesMy Babies: HF Drill pressHF Pipe Bender3   4.5" Black and Decker angle grindersLincoln Electric PROMIG 175that´s it!
Reply:I think if I understand Weazy correctly he is trying to describe the stack dimes look "so that the weld looks like fish scales" that one gets when Gas or Tig welding. No one I know & trust when it comes to the use of a mig welder thinks they are the strongest. Most of the comments I have heard on this where made in regard to welding aluminum.
Reply:When stick welding with 6010 you need to stitch the bead along, giving it that stack of dimes finish. This is necessary to preheat and scour the metal ahead of the weld pool. As far as mig welding steel, I don't see any advantage to stitching the joint along. Could you just clarify that when you refer to weaving you are talking about side to side in the joint, as opposed to stitching front to back along the joint? What I've learned and practiced in weaving is it can be used on flat and vertical-up joints, but not on fillets or overhead. These should be stringers only. What position are you welding in? And let's see those pics!If you don't have the time to do it right, then you definitely don't have the time to do it over.
Reply:The sort of torch motion required for the GMAW process depends entirely on the position, the fillet size required, the wire size, wire speed, and heat output.  Generally speaking, some sort of non-linear torch motion is required unless you're running a stringer root pass for a multi-pass weld or you're running hot and fast with GMAW-spray.  The trick to torch-motion in any position is to keep the arc out of the pool, it should be ahead of the pool or you won't achieve proper penetration.  Following that, it's just a matter of figuring out what kind of motion is required to achieve the necessary cross-section in a given position.  For example, on a horizontal fillet you'll want move quickly across the bottom of the fillet and pause slightly on the top as the pool will tend to slump with gravity.There are several techniques that I am sure that people here will mention, which should give you a good starting point.  Following that, the best thing to do is to practice a lot with various positions and focus very closely on what you're doing.  You want to watch the pool and see how it moves in different positions and how you can move it around with different torch motions.-Heath
Reply:Originally Posted by halbrittThe sort of torch motion required for the GMAW process depends entirely on the position, the fillet size required, the wire size, wire speed, and heat output.  Generally speaking, some sort of non-linear torch motion is required unless you're running a stringer root pass for a multi-pass weld or you're running hot and fast with GMAW-spray.  The trick to torch-motion in any position is to keep the arc out of the pool, it should be ahead of the pool or you won't achieve proper penetration.  Following that, it's just a matter of figuring out what kind of motion is required to achieve the necessary cross-section in a given position.  For example, on a horizontal fillet you'll want move quickly across the bottom of the fillet and pause slightly on the top as the pool will tend to slump with gravity.There are several techniques that I am sure that people here will mention, which should give you a good starting point.  Following that, the best thing to do is to practice a lot with various positions and focus very closely on what you're doing.  You want to watch the pool and see how it moves in different positions and how you can move it around with different torch motions.
Reply:hey, thanks for all the opinions guys, i will be getting a sh!tload of pictures very soon, i have been meanign to bring home soem stuff from work but i havent.... as soon as i get the materials home i will get heaps of pictures and post them for you to look at.....and yes i mean horizontally doing the weave, and by the weave, i mean like go forward, then go back and let the weld pool build up, so that it give the stacked dimes effect as mentioned earlier...... i have no problems doign this, as i do it every day and can do it with ease, bringing out a nice clean, even weld with even toes and good penatration.... when i get the pictures i will post them asap so you can see what i mean, thanks for the help guys.... greatly appreciated"One World...One Muay Thai...Muay Thai Never Dies..."
Reply:I personally like the whip, but it has to be done at a faster pace.my technique is to move ahead of the puddle pause let it fill whip it back slightly and quickly, once you hear the crackling on the back whip move to the front of the weld pool and repeat.another technique i like is to just step it.pause let it fill move ahead and pause lt it fill and so on.you can move along a seam at a steady pace, but it is harder to keep the weld pool the same size an if you slip you will see where you did in the weld.a wise man once told me not to be afraid of movement!