Learning the realworld way....

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Hi guys,The wall of text begins now!I'm working on bettering my welds with my mig machine. I have been reading, scoping photo's, and trying to take in everything I can really. Now I'm starting to form some questions about the process and some things I'm running into. I really don't mean to be a pest (*insert flatery here*) but you guys are all so ****** good, I'm hoping I can get some light to shine on my subject  I have been playing with different thickness of metal and heat settings of course and running into a few snags.1. Sometimes I start to weld something and when I pull the trigger I get a "pop..pop..pop..pop" and small clumps.2. Other times the weld will take off, but the sound will change from the sizzle of eggs so to speak to a hummm, when this happens the wire seems to burn back from the work and a small bubble starts to form at the tip of the gun.I'm going to start working on some projects and will require 1" DOM .083, I've been trying to use the circle weaving approach but sometimes the welds look great most of the time they just look like crap  I can't allways seem to get the welds to stack on top of each other they seem to flow into a wider straight bead.Should I continue to try this approach or stick with the straight and narrow beads?I hate to throw all this out at one shot, and REALLY appreciate the time anyone spends to read and reply to the puddle I'm creating
Reply:It is mostly practise like even if you learn everything about how to weld right you still won't be able to do it right intill you practise it. For the Mig when the weld gets going it should sound like a bunch of continious poping. Try looking behind what you weld intead of the arc when welding because then you will know what to adjust.
Reply:I for one talk a lot ot talk, only I know for certain whether Im all that and a box of timbits IF it Catches...Let it Burn
Reply:Hi, 1- either too high wire speed or not enough heat. 2. Too high heat or not enough wire.Try  just one thickness of material at a time. Don't jump around if you can help it. The hardest part of welding isn't the welding, its the troubleshooting. Get your berrings on one thickness and you will develop a feel for whats happening. Hope that helps a little.B
Reply:Ricker -I am certainly not an expert, and am maybe a couple of hours ahead of you in experience :-)A couple of things to consider:First, you need to keep the electrode fairly close to the base metal - 1/4" to 3/8" is what Miller recommends. You may have too much "stickout" which could be causing the pop-pop-during the weld. Second, MIG is very fast. If you are trying to weld at the same rate that you would with OA, you will just build up a big fat pile of weld behind your gun.Third, make sure the base material is squeaky clean. Most metal stock has a pretty rough surface and wire brushing will not do a very good job of getting down into the pits and cleaning out junk. You should sand or grind the surface to smoothness, then use a degreaser like acetone, or MEK or even Formula 409 or Simple Green to get all the oils off of it. On thicker material, it helps to bevel the edges too. I figure I spend about 10 minutes of prep to every minute of actual welding. YMMV.The guys are right about the practice. There are no born welders, just folks who are willing to play for hours trying different things until they start to get the hang of it. I'm not there myself, but at least my MIG welds dont look like they have arthritis anymore.Revenos
Reply:Originally Posted by RickerHi guys,1. Sometimes I start to weld something and when I pull the trigger I get a "pop..pop..pop..pop" and small clumps.2. Other times the weld will take off, but the sound will change from the sizzle of eggs so to speak to a hummm, when this happens the wire seems to burn back from the work and a small bubble starts to form at the tip of the gun.
Reply:I ran into that humming problem you describe when I first started Miggin but it was such a long time ago I can't remember how i fixed it or if it fixed itself.  It doesn't lay down a weld when that happens, huh?  Sorry I can't help much but if somebody knows the answer to that particular problem I'd like to hear it cuz now I'm curious.
Reply:note the title of the threadnow its time to figure it out the "real world way"   ...zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Originally Posted by WHughesTry  just one thickness of material at a time. Don't jump around if you can help it. The hardest part of welding isn't the welding, its the troubleshooting. Get your berrings on one thickness and you will develop a feel for whats happening. B
Reply:Number one sounds like a cold start or voltage too low.  Number two sounds like you're getting into globular transfer or simply have your voltage set too high.I'm assuming that you're using short-circuit transfer and it might help if you told us what kind of welder you're using.  The 120VAC units often have to be run at the edge of their capabilities and have a tendency to get tired as you're welding with them.  That is, they start to get hot and I believe the voltage starts to sag.  To get very consistent short-circuit MIG welds you need to do everything you can to keep the voltage and the wire speed consistent.To keep a consistent wire speed, you need to make sure that the gun lead is as straight as you can make it.  Avoid having the slack lie in a coil on the ground and don't have any sharp bends in the lead.  Make sure the liner, drive rolls, and wire are clean and also make sure that the tension on the drive rolls is properly adjusted.  A common error is to use too much tension which sets a bend in the wire causing it to feed poorly.Consistent voltage is also important and perhaps not quite as obvious to maintain.  The material should be properly prepared and cleaned as mentioned above.  Someone also mentioned keeping a consistent stickout, which is also important.  What hasn't been mentioned thus far is the need for a good ground.  Make sure that the ground clamp is attached to clean metal and that it is clamped as near to the welding as is convenient.  Also make sure that the line voltage is sufficient by using thicker gauge extension cords that are as short as possible and connected to an outlet that isn't too far from the breaker panel.  The last bit about extension cords is also a pretty common problem with 120VAC MIG welders connected to questionable 15A outlets with too long or too thing extension cords.Once you've accounted for all the things that could create inconsistencies, then it's time to dial in your arc.  Use the door chart, or Miller's MIG Welding calculator to figure out what your voltage should be for a given thickness.  You should also have an idea of what the wire speed should be.  Get yourself a piece of scrap similar to what you're going to be welding on and set it up such that you can run a stringer bead on it with one hand and adjust the wire speed with the other.Start the arc and try to keep your stickout a consistent length.  I usually do this by resting the nozzle on the material.  Adjust the wire speed with your other hand as you're running the bead.  If you got your settings right, it should give you a decent short-circuit arc to begin with (frying bacon sound).  Turn down the wire speed until you start to get burnback and then turn it back up until you start to get stubbing.  The optimal setting should be somewhere in the middle of that range.  It should be obvious as there will be a very pronounced crackling sound and it should feel just right.Following that process, weld up a test piece of the same thickness and joint type that you intend to weld and then check for penetration.  You could either do destructive testing by banging it apart with a hammer or cut through the weld and etch it to see how things went.  I generally like to be in a range where I am almost but not quite burning through the material that I'm welding, but I also have a fair amount of experience and like to run hot and fast.  Someone without a lot of experience might like to run a bit cooler.  If you find that you aren't getting enough penetration or that you're running too cold, bump the voltage up a bit and then go through the procedure again to set the WFS.  If you're running too hot, bump the voltage down a bit and do the same.After following this procedure a few times, it should be very easy to get an optimal short-circuit arc dialed in very quickly.  I had to learn how to do this as my rig has no door chart or recommended settings.-Heath
Reply:in practice time - start hot an fast , then - you can adjust to your needs but it all comes down to stinger time -practice-practice-ect..... stay with one thickness on metal till you do good with that then go up--1/8 -1/4 good to staRT