tie ins with mig

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is there any good way to tie in with mig? i try and tie in but it just leaves a big hump or i don't get up close enough to it and then it just seems like there is a space in between welds.
Reply:What is thickness of base metal? Mild Steel I presume?  What is your voltage and wire feed speed set at? If you are getting a high ropy looking bead with a big hump, try increasing your voltage by a  couple volts, then try again. Just remember that voltage controls the height and width of the weld bead, and that wire feed speed is current, (or amperage) Give us a little more info, and we should be able to give you some good parameters to start out with. As far as your comment of not being close enough, depending on if you are in short circuit transfer (typically 22 volts or less) or spray transfer (which can start at 25-26 volts and up, depending on the gas mix) Your contact tip to work distance should be about 3/8" for short circuit, and 1/2" to 5/8" for spray transfer.
Reply:Shoot for the center of the crater you leave.  Sometimes I find myself backing up into the puddle (habit) when stopping a weld, so, when I restart, I get a hump.  When you restart at the craters center, do a quick circle to outline the crater, gotta be quick.  Let me try this again...start arc at center of crater, outline crater quicker than travel speed, continue bead.  Love to here if anyone else has a better method myself.Various GrindersVictor Journeyman torch200cf Acet. 250cf oxygenLincoln 175 plus/alpha2 gunLincoln v205t tigLincoln 350mpEsab 650 plasmaWhen you can get up in the morning, Its a good day.Live each day like its your last.
Reply:Originally Posted by DoolittleShoot for the center of the crater you leave.  Sometimes I find myself backing up into the puddle (habit) when stopping a weld, so, when I restart, I get a hump.  When you restart at the craters center, do a quick circle to outline the crater, gotta be quick.  Let me try this again...start arc at center of crater, outline crater quicker than travel speed, continue bead.  Love to here if anyone else has a better method myself.
Reply:awesome! i am in school right now and am close to finishing the mig process. my instructor gave us all a blue print and we had to execute it. i had to do an all around fillet groove. anyways, i was on short circuit at around probably 17 or 18 or so, and i was using 1/4 steel. my welds looked good accept for my tie ins which kind of sucked. also when i do wrap arounds on pipe, i find it hard to get a good tie in with those as well. i never would have thought about starting in the center of the crater cause that is a no no in stick. ha ha. i'm gonna give it a try tomorrow in class. i start spray tomorrow so i am looking forward to something new!! thanks everyone
Reply:Originally Posted by zeezawesome! i am in school right now and am close to finishing the mig process. my instructor gave us all a blue print and we had to execute it. i had to do an all around fillet groove. anyways, i was on short circuit at around probably 17 or 18 or so, and i was using 1/4 steel. my welds looked good accept for my tie ins which kind of sucked. also when i do wrap arounds on pipe, i find it hard to get a good tie in with those as well. i never would have thought about starting in the center of the crater cause that is a no no in stick. ha ha. i'm gonna give it a try tomorrow in class. i start spray tomorrow so i am looking forward to something new!! thanks everyone
Reply:zeez,  one reason you might be having problems with your tie-ins... You mention you were running 17-18 volts on 1/4" steel,  I usually run 17 volts on 12ga -11ga sheet metal.  I think your machine is set to low. Try running your volts up to say 21.  You could be just running to cold and causing the problem...I'm a Lover, Fighter, Wild horse Rider, and a pretty good welding man......
Reply:rojo - is it good to end weld passes on corners? i could have done that, but i guess i thought i heard you shouldn't do that. i'm not trying to be a smart *** or anything, i'm just curious.
Reply:It's wrapping the corner, just a tiny bit. If the welds were not good, then it would be a bad idea. All you need to do is to roll the corner, not run into the flat. Sometimes with round tube, you don't have much of a choice, you have to stop somewhere.
Reply:gotchya, ya, i am new to all this welding stuff, so i am trying to learn as much as possible. ha ha.