pinhole at end of bea

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I am a novice welder and occasionally get a small pinhole at the end of my bead.  I am working on some 3x1 16 ga tubing that I had to roll into 30" diameter circles so I cut slots every couple inches so it would roll better and welded up after.   This is not a critical structure (16ga) but would like to prevent this in the future. This was done with mig using .035 wire and c25 at about 15cfh and I was pulling it.  It had a slight gap that closed up at the corner where the pinhole occured.
Reply:When you come to the end of the weld stop and count to two and then just hit the trigger a couple of times and fill in the hole....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:I tried dwelling at the end to fill it in and pulling the puddle further past the corner but it still would pinhole.   I could watch it do it, as weld would cool from Red hot I could see it form.  Wasn't sure if it had something to do with heat dissipating differently at the corner.   I will try holding longer and see if that helps.   16ga is kinda sensitive with the heat.  Had to play around with settings and technique to get past the welded seam without blowing through. Sent from my SCH-I545 using Tapatalk
Reply:Don't hold longer. Stop, wait a second or two, then hit the trigger and add a bit more filler metal to fill it in, just like zapster said.JasonLincoln Idealarc 250 stick/tigThermal Dynamics Cutmaster 52Miller Bobcat 250Torchmate CNC tableThermal Arc Hefty 2Ironworkers Local 720
Reply:So double tap at the end.   Gotcha.   And here I thought double tapping was only useful in shooting.  Thanks guys. Sent from my SCH-I545 using Tapatalk
Reply:Originally Posted by Going nowhereSo double tap at the end.   Gotcha.   And here I thought double tapping was only useful in shooting.  Thanks guys. Sent from my SCH-I545 using Tapatalk
Reply:To me it seems your arc length changed when you rounded the corner. The beads look like you went further than where your pin hole was. I would just focus on your stick out and try and keep it more consistent when getting into contour changes. If you long arc your stick out and it sputters you will poke holes in your weld while it's still molten. It throws the whole parameter setting off for a bit on the machine like a car if you play with the timing. Was there a lot of spatter on the corner before you wire wheeled it?I hate being bi-polar it's awsomeMy Heroes Have Always Been Cowboys
Reply:I welded both sides of tubing first going just past the edge.  Then welded the "face" downhill skipping 2 joints to prevent to much distortion.   I also welded 1" sq tube on each side to minimize shrinking.   I found downhill was best way to prevent blowout at the weld seem.  The joints were a pain to see because they were so tight, I whiffed on a few and ground them out and redid.   I thought my stick out was okay and there was minimum spatter.   I believe it was about 140 cuts and welds.Sent from my SCH-I545 using Tapatalk