Help with plug welds

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I searched the site but could not really find any threads with tips on how to do a plug weld.  I also searched the web and found a few sites, but they were all referencing doing it with a mig welder, and I am trying to do it with stick.So I am trying to weld 12ga cold rolled steel to .065 square tubing.  This is for my insulated smoker that I am building so I have the whole frame build and the interior lining done, and now its time to put the skin on the outside.  I got high temp insulation to go between the inner and outer wall (good to 1,000 deg F).I tried to do the bottom piece of the smoker this afternoon with it flipped upside down.  The sheet that i am welding on is 28x36 so I drilled a 3/16" hole every 2".Originally I tried using 3/32 7014 at 90A  I filled the hole and everything looked nice and pretty but when I unclamped it there was no fusion to the bottom piece of metal.The technique I was using was to place the electrode in the bottom of the hole and strike an arc and fill up the hole.  But I am guessing either the electrode was too large and it just melted the 12ga sheet metal and the weld rested on top of the tubing.I then switched to 1/16 6013 at 60A and did the same technique making small circles as the puddle filled up the hole.  This time there was fusion to the base metal but after I popped off the slag there was a small hole which was not filled in.Any tips or tricks you guys can share would be greatly appreciated.  I can easily drill the holes larger because it would be a lot easier to use a 3/32 rod instead.  What size hole should I drill for that diameter rod?ThxGarrett
Reply:I personally would make your holes larger in diameter, like maybe 1/2" or larger if you have a bigger bit, and then just weld around the edge of the hole, joining the pieces together.  As opposed to trying to fill up the entire hole.
Reply:Definitely make the holes larger . . . I use 3/8 when plug welding 10 gauge material.  I'm  using MIG, but I think that would give you room to finish the weld without trapping flux.  Just start your arc on the bottom sheet and fill the hole from the center outDynasty 300DXSmith He/Ar gas mixerMM350PHobart Handler 120Smith LW7, MW5, AW1A
Reply:In as much as you have 3/16" holes every 2", I would change the plugs to slots 2" long.
Reply:Although the rods that you used should be okay for plugs, I would suggest that you go to a 6011 or 6010 if you have them.  Thet are better penetrators.StephenMillermatic 251Miller Syncrowave 200Miller 30A SpoolgunHypertherm Powermax 30Etc., etc., etc.............Cancer Sucks!