please judge my welds

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Hello a while back I posted having trouble getting a good bead going with my mig welder (Lincoln Electric mig pak 180 with 75/25 shielding gas) on 1/8 x 1  flat bar. as per listed inside the welder door the setting should be 8E setting. I have the shielding gas at 22 l/min. I have stick welded in the past with great results with this welder I cant seem to get it right I see 1. not much penetration and 2. the bead doesnt look right. too fast? too slow? Im looking for suggestions/tips thanks and by the way this forum is the best!Last edited by franklarabie; 02-12-2009 at 02:22 PM.
Reply:A little fast...Slow down and at the end, hold the gun still and fill the crater on the end..Penetration looks okay. Its hard to tell on this piece. Is this a lap joint or a butt?I see from your heat lines, you are probably having problems with gun angle. You can see you concentrated the heat more on one side than the other.  The wire should feed directly into the crack.  On something this small, weaving is not necessary.  Angle your gun into the puddle and watch the "tilt" of your arm and the angle of your wrist as you may not be keeping the neck of the gun nearly perpendicular to your work.Last edited by lugweld; 02-12-2009 at 02:41 PM.Esab Migmaster 250Lincoln SA 200Lincoln Ranger 8Smith Oxy Fuel setupEverlast PowerPlasma 80Everlast Power iMIG 160Everlast Power iMIG 205 Everlast Power iMIG 140EEverlast PowerARC 300Everlast PowerARC 140STEverlast PowerTIG 255EXT
Reply:its a butt weld and where you see the crater on the right it's the start believe it or not. How can I correct this problem?
Reply:That crater isn't the start, that's the end.   I can tell by the direction of the weld.   You welded left to right in all 3 pics of the topside of the weld.   Hold the torch a bit with the trigger down at the end of the weld to fill the crater before releasing the trigger and lifting the torch away.You either need to gap the plates apart from eachother, or bevel the edges, or use more heat in order for the weld to penetrate instead of sit on top of the joint.   You did get some penetration so you're not too far off.  Crank it up a bit more, or change the joint prep as noted above.Follow Lugweld's advice on the torch angle and travel speed.Overall, you're doing good, moving the torch fairly straight and fairly constant speed.Last edited by DesertRider33; 02-12-2009 at 03:13 PM.MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op
Reply:Exactly,A seasoned welder can tell where the weld started or ends.  The V's or U's always point away from the direction of <<<<<<<<<travel.Esab Migmaster 250Lincoln SA 200Lincoln Ranger 8Smith Oxy Fuel setupEverlast PowerPlasma 80Everlast Power iMIG 160Everlast Power iMIG 205 Everlast Power iMIG 140EEverlast PowerARC 300Everlast PowerARC 140STEverlast PowerTIG 255EXT
Reply:sorry for my ignorance. Correct the crater is the start I spun the pieces when I took the pictures. I will try to hold the torch to fill the crater next time. You said to leave a gap how big of a gap would be neccesary?all part of the learning process I guess thats why I love this forum! thanks guys illl try that and ill post new picturesLast edited by franklarabie; 02-12-2009 at 03:27 PM.
Reply:Try a 1/16" to 3/32" gap.  Tack the pieces at each end before you make the weld to maintain the same gap while welding.That little dot of weld before the start on the left, was that your tack, or did you touch the wire down with the trigger pulled, then jerk the torch forward and start welding?MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op
Reply:yes it was a tack. I had a long peice of steel and tacked it then cut up peices to practice on. I also had approx 1/16 inch gap to experiment. Well ive tried the torch angle like you mentioned and wow a difference right there more penetration! the crater, I tried to hold it a little longer but i this it wasnt long enough. here are some pics of the retry.  let me know what you see wrong thanks againunder side
Reply:Now you are on the right track.You did fill the crater. a little manipulation of the torch may help just at the last.You might also want to brace off a little better.  It looks a little wobbly.Esab Migmaster 250Lincoln SA 200Lincoln Ranger 8Smith Oxy Fuel setupEverlast PowerPlasma 80Everlast Power iMIG 160Everlast Power iMIG 205 Everlast Power iMIG 140EEverlast PowerARC 300Everlast PowerARC 140STEverlast PowerTIG 255EXT
Reply:Torch angle, gap between plates.  You're getting there.  When I'm doing continous welds with MIG on light gauge metal, I make several tacks to keep gap alignment.  When I start the weld on the end, I start the arc ahead of the end, move back to the beginning and weld right through where I struck the arc (this works well in arc welding also).  Eliminates that "cold start" hump.  However, don't do this in any code welding as it may not pass x-ray.Typical electrode angle on a flat weld with ARC is 5-15 degrees leaned forward in the direction of travel.  Electrode should be 90 degrees to each SIDE.  I just reverse the angles when MIG welding as I'm generally "pushing" the mig torch.  Lean your torch 5-15 degrees back over your completed bead, keep the nozzle 90 degrees to each side, wire centered on the puddle.  At the end of the weld, I actually make a small circular motion to fill in the crater.  Works good.Another hint when doing sheet metal.  Do the "Back Step" method of welding to help prevent distortion from welding heat.  Prepare your pieces, tack along the entire length of weld.  Instead of starting from right to left welding (if right handed), start on the left end, move your MIG torch in about 2" from the end, weld RIGHT to LEFT that 2".  Allow to cool a little, move another 2" to the right from that completed weld and repeat the procedure.  Repeat until your entire weld is done.  If you don't care about warping and distortion, just weld the regular way.Looking good.
Reply:Looks good, you got the penetration now.  MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op