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I bought this 250A 3ph MIG some months ago:http://www.iskra-varjenje.si/html/ang/ecoline.htmland today have had the pleasure of attacking itlike a real beginner Before this, I had dug around info and watched a few videosto be a bit prepared to have a little success but like Ilearned with stick and tig welding, things are not so easywhen youre on your own, so I have a few questions.Before the questions, a bit of info on the settings/machine.The machine has following features: LED display of instantaneous Amps or Volts,10 step volts, continuous wire feed speed, burnback setting, 2T,4T,spot,gas test.Wire 0.8mmMaterial 2mmTo get ball park on wire speed, I used 39.4A/mm material thickness in 2/min/Amp formula(as seen on wledingtipsandtricks) and I had measured wirefeed speed on severalsettings, so it was easy to get the setting approx to what I thought it should be Voltage : In machine instructions, it mentions 1mm&1,2mm wire for 2mm material 19-19.5V,So I tried setting something a bit lower since I was using 0.8mm wire (17.5V but thisvaries a bit depending on distance to workpiece)Current: I saw 86A on the meterQuestions:(1)Again maybe to some basics on identifying what is wrong with the weld on the photo& what should I be looking / hearing for ? (2)When adjusting/increasing the wire speed(on two voltage settings), I did get slow sizzling , then fast sizzling and followed bybroken tacking and a lot of spatter which sizzling should I aim for and what else should I look for to be sure I am on the right voltage/wirespeed ? (3)When cleaning the nozzle and tip is a steel or brass brush supposed to be used(tip looks like copper, so I presume anything harder than a brass brush would notbe good) ?(4)How do you incorporate the burnback setting when tuning in the wirespeed/voltage ? How long should the wire stick out be after a weld ?I presume you always cutoff the balled end / shorten the wire after each weld (I didnt on a couple of occasions and noticed bad starts) ? Attached Images
Reply:What gas are you using? Looks to me like straight argon. I don't know the metric thing to well but it looks cold. Knowing gas type, flow rate, and wire type would help.Miller xmt304, Miller S22 p12, Miier Maxstar SD, Miller 252 w 30A, Miller super32p12, Lincoln Ranger 9, Thermal Arc 181I with spoolgun, Hypertherm 10000 ,Smith torches. Esab 161lts miniarc.
Reply:weld 3 is perfect. 17 too fast travel. 9 too high voltage.Hope this helps.
Reply:MJD - when I wrote this post first time, I had a timeout and the post was lost , secondtime around forgot to give the gas details - here we use 82/18 for steel.mikecwik - if it's not too much trouble, could you indicate which welds you arereferring to and what aspect of the weld makes it good ? From your comments, looks like there's hope for me yet - at leastI was pleasantly surprised how little if any spatter there is and how easy it is tolay the bead down compared to stick welding (not that I'm "good" at that either). Forgot to mention - looking from top of phototowards bottom, I initially started with 8l/min of gas and a lower voltagesetting, then towards the end(bottom), I'm at the next voltage setting and 10l/min of gas.In between, for some of the welds, I was setting the sizzling and trying toweld, so it's not a weld with one continuous setting. Any feedback about my other questions especially about the sizzling ? With that infoI can hopefully get closer to the right setting and post some more pictures.Also one more question - I did initially go over the steel with a grinding disc. Now withall these small welds, is it enough to just wirewheel over and keep welding (I'll try to be neater ) ?P.S. do I need to wire brush the welds before taking photoor is color etc. relevant for identifying how good the weld is/probswith gas etc. ?- just interested anything/everything you're lookingat to judge the weld.Last edited by vjeko; 12-01-2013 at 07:15 AM.
Reply:From what I see is your standoff is waaaayyy too long. Looks like your wire is floping around while trying to maintain an arc.Push the cup right up as close as you can, get your face off to the side and right in there and slow the heck down.Good luck.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:shovelon - thanks for the feedback. I tried to aim for somewhere around 10mm (3/8") stickoutbut as I said - quite a few of the welds were one hand behind on the wirefeed and theother in front with the Mig gun without proper distance control - any answers to other questions ?If I don't get any more clarification on the sizzling/voltage, maybe best if I try a properweld on the low setting and send a photo again.
Reply:Originally Posted by vjekoshovelon - thanks for the feedback. I tried to aim for somewhere around 10mm (3/8") stickoutbut as I said - quite a few of the welds were one hand behind on the wirefeed and theother in front with the Mig gun without proper distance control - any answers to other questions ?If I don't get any more clarification on the sizzling/voltage, maybe best if I try a properweld on the low setting and send a photo again.
Reply:No you don't need to clip off the ball. Shorten the burnback time and your ball will be smaller. Your arc bubble will be about 1/3rd of your wire stickout, and driven wire will be about 2/3rds. So if your stickout is 3/8ths of an inch, your arc is 1/8", driven wire 1/4". From what I see in your picture, you have at least 1/4" of burnback, add that to what I see at least 1/2", and that total is 3/4" stickout. Did that make sense?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:OK, I worked a bit more on this / some more feedback would be appreciated.Shovelon, from your comment about recessed tip, and further reading, I came to the conclusion that for short circuit transfer, the tip should not be recessed but for spray transferit is better that the nozzle covers the tip for better cooling and weld protection - if thisis not correct please advise. I therefore further shortened the nozzle (maybe didn't flattenthe nozzle end perfectly) as per photo - any further advice on this ?You're right about pulling back - I did it quite a few times again but mainly as the machine is positioned ackwardly (behind me) and when fiddling with thewire speed knob or taking a peak at the instantaneous voltage/current, I was puttingdown the bead "by hearing" Attached Images
Reply:I went back to trying to identify what voltage/wire speed settingis correct, would appreciate your feedback (hopefully I will thenbe able to better identify the right settings for other thicknesses- need to work on 3mm & 4mm after):Material 2mm mild steelWire 0.8mmGas Argon/Co2 82/18On the photos you will see 3 weld beads (view from top & underneath)Before doing the weld beads, I tried to check the voltage/current/wire speedThe voltage knob has 10 steps, wire speed is continuous (as mentioned before,I have measured wire speed at quite a few settings, so I have includedit here in case it helps)."V4" indicates step 4 on the voltage knob. I did not do a V1 weld as Ifelt there was insufficient power - depending on wire speed, the wireseemed to be wandering as if it was not melting fast enough and itwas pushing against the surface being welded. The other thingI noticed was that there seemed to be a much more pronounced"sizzling capability" from V3 and above.V4 16.6V 90A wire speed 3 = 88mm/sec or 180"/minV3 16V 90A wire speed 2 = 68mm/sec or 160"/minV2 15V 54A wire speed 1.5 = 51mm/sec or 120"/minP.S. The chief engineer at the company which makes the machinesaid that the machine can certainly work in spray transfer modewith this gas mix and 0.8mm wire Attached Images
Reply:V4 looks the best of all. The toe of the weld looks well wetted in and the width looks about right. V3 has some possibilities but is a tad too cold. The bead looks too tall and the toes are at a much more vertical angle than those in V4. To me V3 looks like it has a bit too much wire for that voltage. I will admit that sometimes the flash will make beads look harsher than they really are, so it is possible that V3 is a bit better than it looks, but I still think there is room for improvement.Wire is a bit on the large size for material that thickness for my taste. It's certainly doable and I'd run that size if I was also doing larger work. Dropping down to say .06mm ( .023) wire might help make V3 work a bit better. Depends a lot on what you are trying to accomplish. In a production environment where time is money, running bigger wire faster is fairly typical. I prefer to run a bit slower on my own projects, and smaller wire often allows me to fine tune things a bit more than running wire the next size up does. It gives me a bit more control over the weld puddle and allows me to move a a bit more relaxed pace when making the weld..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:Any comments about post #9 about the nozzle length /recessed tip ?Do you use a brass or steel wire brush for cleaning the mig nozzle/tip ?Regarding V4 - what do you mean by "width looks about right" ?What is the penetration supposed to look like (on backside) like V4,V3 or V2 ?OK, will try to get some 0.6mm wire when I get the chance.Last edited by vjeko; 12-06-2013 at 06:42 AM.
Reply:At the school, so many of the nozzles are so F'd up I hardly pay much attention to them unless the gas shieldind is bad. I tend to measure stickout from the gun tip, not the nozzle. There are a few "tricks" I've seen guys do with thin sheet. One is they pull the nozzle out away from the tip. All this really does though is increase the distance from the gun to the work. I can do the same thing without extending the nozzle. Only advantage of the extended nozzle is that they get a bit better shielding gas coverage if there is a slight breeze since the gas is contained longer.As far as cleaning the nozzle, I don't use a brush. I usually use the tip on my welpers ( mig pliers) as a reamer and just twist it around inside. At home I sometimes spray the nozzle with anti spatter or dip it in mig gel to reduce the spatter and make it easier to clean. At the school, we run 92/8 and the spatter is pretty small. Only time it becomes an issue is doing vertical and overhead when molten steel drips into the nozzle or the kid drags the nozzle in the puddle. Than most times if you just bang the nozzle on the work, the stuff comes right out, though occasionally if it's really bad, you might have to grab it with the pliers.As far as width, there's usually a width to height ratio that is about "right" depending on material thickness. What I see in V4 just "looks" right to me. Now beads on flat plate always stand a bit taller than the same settings on a joint. I kind of have a feel for what looks about right for beads on flat plate. I will admit it's tough to judge without a good reference in the pict, but lots of experience judging beads on flat plate makes me confident of what I'm seeing.As far as what the back looks like, heat marks generally don't tell you anything about penetration. I can make beautiful heat marks on the back of thin plate with the machine set way too low to give good penetration. All it tells me is it got hot back there. If you really want to know penetration, you need to cut and etch the piece so you can tell the depth of fusion for the weld. The only time you can really tell if you are getting penetration from the back on flat plate is when the bead is melting thru. I see that in that top "bead". Chances are then you have too much penetration. On flat plate it's tough. Looking at the back I'd say the bead that show on the back was penetrating too much. However that's about right if you were going to try and do a tight fitted but joint. Then I'd want to see the machine set that hot ( if not just a tiny bit hotter) to make sure you could punch thru both pieces 100%. ( see below) Normally, especially on thin material all that extra heat means you'll blow holes thru if your fit up isn't perfect and all that extra heat will tend to warp things.Joints are a bit different. If it's a but joint, you should be able to see if you are going thru 100%. You should not see that nice crisp line from the original joint. Same applies to an outside corner with the inside edges touching. You should just begin to see the bead penetrating thru the back. Fillet joints like laps and T's though rely on the reinforcement in front of the joint vs penetration like the other two. Because of the extra mass, you seldom see as much penetration on these unless you bevel..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:OK, thanks - one thing still unclear and then I think it is time to do a bitmore practice and start making something simple and get further feedback then.Regarding the nozzle - it wasn't clarified - should the nozzle be shortenedso that the tip sticks out and how much and in which case ?Last edited by vjeko; 12-06-2013 at 10:26 AM.
Reply:I generally have the tip flush with the nozzle if I can set the gun up that way. I try not to have the tip protrude from the nozzle if possible since you don't always get good gas coverage it it's set up that way. If the tip is recessed, it's not that big of a deal, but it might cause you to have a longer stick out, and thus you might have to adjust your voltage up to make up the difference. When you get up into voltages where you are running in spray, then having the nozzle sticking out past the tip can help some with gas coverage because you often have a longer stick out with voltages that high..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:OK, so I made a boo boo with the nozzle this time - won't make that mistake in the future.Thanks - back to practicing.
Reply:Yours isn't sticking back all that far. I don't know how it attaches, but you might just be able to pull it forward some. Even where it is I doubt it will cause major issues. I've seen a lot worse at the tech school after the kids abuse the nozzles. The only reason I'd mess with it is if you are having issues with poor gas coverage. If your coverage is fine, don't worry. If coverage is spotty or poor, turn up the gas a bit and see if that helps..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 |
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发表于 2021-8-31 22:39:03