First MIG welds ever. Please critique.

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Hi guys,My Passport Plus finally arrived, and I wasted no time making use of it. I'm working in my garage with nowhere to weld except the concrete floor, so my first practice session is actually putting together the frame for a welding table. I figured I'd might as well jump in with both feet. The material is 1-1/2 x 1-1/2 x 1/8 tubing. I'm using a C25 gas mix at a flow rate of 25, .030 wire, 5.1 volts, and wire speed is set to 52. I ran a few passes over some scrap tubing to find those settings based upon penetration. The main problem I'm having is not knowing what to look for in a good vs bad weld, so please take a look and feel free to speak your mind. If it's crap, go ahead and tell me so, but please also tell me what to try to make it better.Here are a few pics: Attached Images
Reply:Not bad, I like to run my mig a little hotter to keep the weld bead flatter. If you were to grind the weld zone first you will get better penetration. Keep playing and you will find the best setting for that welding machine gas and electrode. Keep good notes.
Reply:They look good, but maybe could be hotter.  Forehand or Backhand? Maybe you could weld through the corners and picking up the bead again on a straight part.Great startDavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:Nice work.
Reply:Originally Posted by David RThey look good, but maybe could be hotter.  Forehand or Backhand? Maybe you could weld through the corners and picking up the bead again on a straight part.Great startDavid
Reply:From a rookie, so take it with a grain of salt. The outside of the corner looks good to me, the top is a little too round, and the inside corner of the "L" looks the coldest, being "A" shaped.
Reply:I think the weld should be "sunk" into the plate a little more.  Try welding some flat plate and look at the other side to see how deep it went in.  For adjusting by the sound of the arc, you can have a really cold weld and the arc sounds like it is supposed to be.  Isn't there a chart in the machine that tells you where to set for the thickness of the material?  This is a good guide.  Once you START with those settings, tune the machine so you get a good arc like you have been doing.DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:Originally Posted by David RI think the weld should be "sunk" into the plate a little more.  Try welding some flat plate and look at the other side to see how deep it went in.  For adjusting by the sound of the arc, you can have a really cold weld and the arc sounds like it is supposed to be.  Isn't there a chart in the machine that tells you where to set for the thickness of the material?  This is a good guide.  Once you START with those settings, tune the machine so you get a good arc like you have been doing.David
Reply:Originally Posted by ManglerSo a cold weld is distinguished by the height of the bead?
Reply:They look great for someone's first beads... Just keep practicing... At least they don't look like chicken crap on the tube... Good luck..and remember BURN IT IN....
Reply:I have never tried the passport. The only thing that I might try is wiggling in the fillet on the inside corner. You probably got good penetration, but the weld has an odd shape. Like it is cold, and it sucked from the side walls. But I do not know that welder and your setup. Did you look inside to see how it penetrated? I am going to guess and say that it is penetrating well. From what I saw of that passport it looked like they designed it to penetrate. Pretty cool machine from what I saw of it.        Sincerely,             William McCormick
Reply:The profile of the bead is part of it, the width, the toe (that is the edge of the bead), the straightness will simply have to be practiced. Two schools of thought concerning manipulation of the whip might be whether to slightly weave or simply run a straight on bead, with no side to side manipulation at all. If you forego the manipulation of a slight weave, the settings on the machine, in my opinion, need to be hotter to accomodate this. Your beads appear to be straight forward, no weave at all. I always find this to leave a tall stacked up bead, compared to  using a slight weave.About heat input, if you don't put enough voltage into the bead, it will not dig in enough and will appear to be a like a worm laying on the table, very round on top and not fused well at the toes. Put too much in and you burn clean through the base metal! We must know how far we will penetrate into the base metal to accomplish sound welded connections. Other wise, we are just guessing and only kidding ourselves. There is the trick of it, getting just the right amount of penetration, too much and you are out of control.Nice machine, you will like it!Last edited by tanglediver; 02-10-2008 at 04:12 PM.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:Originally Posted by tanglediver it will not dig in enough and will appear to be a like a worm laying on the table, very round on top and not fused well at the toes. Nice machine, you will like it!
Reply:I can't pitch in any  suggestion as I'm a newbie myself.  I have about less than an hour's worth of mig time and more on Tig.  I just need to say my beads were not even as clean as yours my first time.  I guess I had it set too cold and just started piling up on the metal like a worm that was described earlier.  You're off to a great start!!  Goodluck!Did you have yours plugged 115 or 220V??_______Miller Maxstar 150 STLLincoln ProMig 140Hobart Handler 210
Reply:Here's one of the earlier ones from today. They did get a bit better as the day progressed, but the batteries died on my camera, so no additional pictures. They definitely looked flatter today.I took the advice and turned up the volts a bit as well as turned down the wire speed a touch. I also changed technique on the way I worked the wire, incorporating a bit more side to side and/or circular motion.Since I'm assembling my table with these welds, I can't see the back side once I'm done. In order to check penetration, I ran a few beads with the new settings on a coupon before I started on the table again.Can someone tell me what the brown spots on the bead are? Attached ImagesLast edited by Mangler; 02-10-2008 at 08:02 PM.
Reply:Originally Posted by William McCormick JrDid you look inside to see how it penetrated? I am going to guess and say that it is penetrating well. From what I saw of that passport it looked like they designed it to penetrate. Pretty cool machine from what I saw of it.        Sincerely,             William McCormick
Reply:Originally Posted by tanglediverThe profile of the bead is part of it, the width, the toe (that is the edge of the bead), the straightness will simply have to be practiced. Two schools of thought concerning manipulation of the whip might be whether to slightly weave or simply run a straight on bead, with no side to side manipulation at all. If you forego the manipulation of a slight weave, the settings on the machine, in my opinion, need to be hotter to accomodate this. Your beads appear to be straight forward, no weave at all. I always find this to leave a tall stacked up bead, compared to  using a slight weave.About heat input, if you don't put enough voltage into the bead, it will not dig in enough and will appear to be a like a worm laying on the table, very round on top and not fused well at the toes. Put too much in and you burn clean through the base metal! We must know how far we will penetrate into the base metal to accomplish sound welded connections. Other wise, we are just guessing and only kidding ourselves. There is the trick of it, getting just the right amount of penetration, too much and you are out of control.Nice machine, you will like it!
Reply:Originally Posted by stormI can't pitch in any  suggestion as I'm a newbie myself.  I have about less than an hour's worth of mig time and more on Tig.  I just need to say my beads were not even as clean as yours my first time.  I guess I had it set too cold and just started piling up on the metal like a worm that was described earlier.  You're off to a great start!!  Goodluck!Did you have yours plugged 115 or 220V??
Reply:Welding is like marriage no one knows anything about it really. Some just get lucky for a while here and there. Ha-ha.You are doing really well. Good choice of machines. I like the way they designed the machine to keep a tight or close arc.       Sincerely,             William McCormick
Reply:Originally Posted by ManglerThat was a good explanation. Thank you. I'm having some trouble getting even penetration across the entire bead. As the bead progresses, the material gets hotter and of course penetration accelerates as a result. I've tried slowing down right at the start of the bead to get the metal hotter but that just results in a fat bead at the start. I haven't figured this one out yet, but will keep working on it.
Reply:I think your still too cold and traveling too fast. Take it as hot as you can on a scrap piece to get an idea of how the puddle acts just before you burn through and then adjust it back just slightly. With your slight weave, be sure to linger at the toes of the weld as you weave back and forth. It all comes down to time spent behind the helmet. Your off to a good start
Reply:The brown spots are metallic vapor that have mixed with air and turned to something else. That is not terrible, however it also means that you are approaching the maximum limits for that wire size. The wire is starting to boil off.        Sincerely,             William McCormick
Reply:Originally Posted by William McCormick JrThe brown spots are metallic vapor that have mixed with air and turned to something else. That is not terrible, however it also means that you are approaching the maximum limits for that wire size. The wire is starting to boil off.        Sincerely,             William McCormick
Reply:Originally Posted by TinbasherI think your still too cold and traveling too fast. Take it as hot as you can on a scrap piece to get an idea of how the puddle acts just before you burn through and then adjust it back just slightly. With your slight weave, be sure to linger at the toes of the weld as you weave back and forth. It all comes down to time spent behind the helmet. Your off to a good start
Reply:As hot as the material will stand, thicker metal requires much more heat, thinner metal won't stand up to so much and so takes less to get the ideal full penetration.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 BibleDannyWhy not...that's how you learn...change things up and pay close attention to the results...I'd try every setting on the welder to become more familiar with it.
Reply:Originally Posted by TinbasherWhy not...that's how you learn...change things up and pay close attention to the results...I'd try every setting on the welder to become more familiar with it.
Reply:Just keep at it.  YOU ARE NOT EVEN CLOSE TO THE LIMITS OF .030 WIRE.  Its best to burn up some wire on test plates or practice stuff.  You need to bond with the machine.  Get to know it like tanglediver said.   Don't worry about the brown stuff.   If its on top of the weld, its impurities that have floated to the top of the weld. Its supposed to do that.  For the brown smoke, don't worry about that either, a wire brush will take it away.You are doing fine.  Keep at it.  You said it your self, as the day went on, the welds got better.  Think of how you will be after 100 hours.DavidReal world weldin.  When I grow up I want to be a tig weldor.
Reply:Originally Posted by David RJust keep at it.  YOU ARE NOT EVEN CLOSE TO THE LIMITS OF .030 WIRE.  Its best to burn up some wire on test plates or practice stuff.  You need to bond with the machine.  Get to know it like tanglediver said.   Don't worry about the brown stuff.   If its on top of the weld, its impurities that have floated to the top of the weld. Its supposed to do that.  For the brown smoke, don't worry about that either, a wire brush will take it away.You are doing fine.  Keep at it.  You said it your self, as the day went on, the welds got better.  Think of how you will be after 100 hours.David
Reply:Hi everyone!David I`m new to this interesting site. I know about stick weld, but I would like to buy a Mig machine to be able to weld copper, etc. and upgrade the quality of my work. Currently, I do iron and wood work. I will post some pics soon. Love to share my pics and watch everybody`s too. In fact, I`m confused in regards to buying a Mig or a Tig. Cannot afford buying both. I`ve read about it and received advised from people, but I`m not able to make up my mind yet.An outdoors sculpture project to be made using forged copper sheet over a steel shaped armature, will need either welding.My concern is what would happen to armature if  used mild steel. Will it rust some and galvanic corrosion stop since its sealed with welded Cu sheet? Should I used stainless for armature?If so, can copper and stainless be welded with Mig? And what is aproximate consumption of copper wire to weld 3/16" sheet? How long would it take to learn TIG weld copper, provided he knows arc weld and bracing.I really need some pro advise on this! Thank you so much. Baculus.
Reply:Originally Posted by ManglerSo I'm approaching the limits of the wire but still running cold?? If I crank the voltage up to run hotter does that mean that I need to go to a bigger wire? I'm running .030 on 1/8" material.
Reply:Originally Posted by ManglerThat's a relief. Thank's, David.I notice that my C25 is down to about 1700psi (it started at 2000). How do you tell when it's time to refill the bottle? I'm hoping it's not too soon... that gas is not cheap.
Reply:Originally Posted by baculusHi everyone!David I`m new to this interesting site. I know about stick weld, but I would like to buy a Mig machine to be able to weld copper, etc. and upgrade the quality of my work. Currently, I do iron and wood work. I will post some pics soon. Love to share my pics and watch everybody`s too. In fact, I`m confused in regards to buying a Mig or a Tig. Cannot afford buying both. I`ve read about it and received advised from people, but I`m not able to make up my mind yet.An outdoors sculpture project to be made using forged copper sheet over a steel shaped armature, will need either welding.My concern is what would happen to armature if  used mild steel. Will it rust some and galvanic corrosion stop since its sealed with welded Cu sheet? Should I used stainless for armature?If so, can copper and stainless be welded with Mig? And what is aproximate consumption of copper wire to weld 3/16" sheet? How long would it take to learn TIG weld copper, provided he knows arc weld and bracing.I really need some pro advise on this! Thank you so much. Baculus.
Reply:Originally Posted by ManglerThat's a relief. Thank's, David.I notice that my C25 is down to about 1700psi (it started at 2000). How do you tell when it's time to refill the bottle? I'm hoping it's not too soon... that gas is not cheap.
Reply:Originally Posted by littlefuzzwhenever your flow meter starts going down.  what size bottle do ya have?  I run 95/5 Ar/CO2, it' seems much smoother than the 75/25 and I get much nicer beads.
Reply:Originally Posted by David RReplace it when it gets down to 50 psi or less.  I run em till empty unless its a critical job.David
Reply:Mangler, I didn't see anyone else mention this so thought I might, you might back off on the gas pressure a tab. Try someplace between 15-20 cfh. I didn't notice what size bottle you have but if you can get by with a little less it will make your bottle go a tab longer. Just a thought. P.S. Your welds look good for just starting, keep up the good work, and keep the pictures coming.
Reply:Sounds like you have a  75cf cylinder.  The flowmeter only reads when there's gas flowing through it.  Whenever you're setting the flowmeter you can unclamp the tensioner on the wire so that you don't run out a bunch of wire, I don't do that but if you're concerned about wasting wire you can.  Also, be careful of the advise given by your LWS.  Just because they sell the stuff don't mean they know anything about it, they seem like they do but....Well they're salesmen, that's about it DewayneDixieland WeldingMM350PLincoln 100Some torchesOther misc. tools
Reply:This newby here learned much from this thread and perhaps I can make a contribution.I grind down most of my welds.  Primarily because it tells me what the weld looks like inside, whether or not a have undercutting, depth of penetration and porosity inside the weld.Secondly because my welds are not the prettiest, yet and I am still experimenting with technique.Self assessment:  My welds are not the straightest or the prettiest.  BUT 99% are good welds, strong welds.  Pretty and straight will come in time...DonScottsdale, AZwww.savagesun4x4.comMiller 180Hypertherm Powermax 30
Reply:Originally Posted by SavageSun4x4This newby here learned much from this thread and perhaps I can make a contribution.I grind down most of my welds.  Primarily because it tells me what the weld looks like inside, whether or not a have undercutting, depth of penetration and porosity inside the weld.Secondly because my welds are not the prettiest, yet and I am still experimenting with technique.Self assessment:  My welds are not the straightest or the prettiest.  BUT 99% are good welds, strong welds.  Pretty and straight will come in time...
Reply:Originally Posted by gnewbyMangler, I didn't see anyone else mention this so thought I might, you might back off on the gas pressure a tab. Try someplace between 15-20 cfh. I didn't notice what size bottle you have but if you can get by with a little less it will make your bottle go a tab longer. Just a thought. P.S. Your welds look good for just starting, keep up the good work, and keep the pictures coming.