Mig question

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hi! ive got a question regarding mig welding, happens that i work in a small fabrication shop, and i am a sort of welder helper and apprentice, i do ofc everything "my" welder tells me to do so, i do also weld some minor parrts ie some square tubing and other minor stuff such as reinforcements plates and other things i dont know what to call them, one question is about the square tubing i mentioned, they are about 6mm thick or 1/4 inch aprox and we do some bevels to them, btw they are U tubing, long butt welds i got to do, but i dont know how could i do it so the bead penetrates all the way through without blowing a hole, (which has happened about 3 times), i try to make kind of deep and i widen up a bit the bevel, even doe it has happened 3 times the thing of blowing a hole or burning thru i think its called, when i see that its going too hot/ too much bevel, or bad fit or theres a gap i do some quick whip and pause or move forth and back in that way ive avoided it, that part ends up being totally flush compared to the rest of the bead and what technique would u guys recommend for long beads, no technique at all doesnt work. and what settings would u guys recommend we use aprox 200amps and 26volts i think is too much for short circuit transfer. thanks in advance Last edited by ianS; 04-17-2016 at 07:17 PM.
Reply:It sounds like English may not be your 1st language from your post.I have a difficult time explaining how to "see" the puddle to students. It's like trying to explain "red" to a blind person. With out refernces, nothing I say is going to make good sense to you. As you practice welding over and over, at some point what you are seeing will start to click and you will hopefully have an "ah ha!" moment and it will all begin to make sense.Most new welders just see the arc. Some will begin to see the puddle but not understand it. I often run exaggerated vertical weaves to try and get students to be able to see the puddle and watch it follow my arc as I weld. however they have to 1st have welded long enough that they have begun to see the puddle for themselves, otherwise it's pointless.Once you can see and read the puddle, everything becomes a lot easier. You manipulate the gun in such a way to get the puddle to do what you want it to do. I've seen guys with almost no mig experience pick it up almost immediately, but that's because they had already been welding with tig or stick and knew how to "see" the puddle. At that point all they really needed to learn was the basics of manipulating it..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:Originally Posted by DSWIt sounds like English may not be your 1st language from your post.
Reply:You can fudge the heat or amperage by pulling back on the gun and giving a longer stickout to reduce heat and closer to increase heat.  Depending on the situation you can change the amps from ten to about a max of 20 amps.  I am guessing that your wire is sticking out past the copper contact tip about 3/8th inch?  When you see the heat starting to give you a melt through pull back to half inch... no more than 5/8 inch.  When you are in control again start moving the gun closer.  If you pull back like an inch you will lose your gas shield and get porosity.  Also if you see the beginning of melt through pull back and get moving forward to reduce the size of your puddle.
Reply:Originally Posted by mikecwikThat is rough DSW.
Reply:I've read some posts by folks on the other side of either pond who have better mastery of English, spelling and punctuation than some of our American born and raised ones who spent too much time playing video games and texting and then sleeping through English classes. Then their schools pass them even though they're damned near illiterate because we want no child left behind.                                           MikeOl' Stonebreaker  "Experience is the name everyone gives to their mistakes"Hobart G-213 portableMiller 175 migMiller thunderbolt ac/dc stick Victor O/A setupMakita chop saw