How to fill voided areas?

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I'm a first time welder. I've been welding a few months with my Hobart handler 180 mig welder. With some of my projects I have trouble filling voided areas between pieces of steel .Mainly areas no wider than 1/4". Usually as a result of an uneven fit.
Reply:1/4" is a huge gap to try and fill. 1/8" is a lot more reasonable. Learning puddle control and how to read the puddle will greatly improve your chances of making this work well. On non critical welds, you can turn the heat down a bit and run a bead along one side to help close up the gap some, then try and weld the rest shut.Best solution is to take a bit more care in cutting and fit up. I usually tell most of the students at the tech school that fit up is 90% of the trick to getting good welds when they go to do their bevel but joints. Those that rush the prep usually fail almost every time. Those that take the time to prep their plates right  usually pass after one or two tries once they understand how the material will react..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:Got ya! So when I do try and fill a gap do I stay with the same settings?Last edited by bnew17; 01-30-2013 at 10:12 PM.
Reply:That would greatly depend on your skill level. For someone with a lower skill level, many times it would help to turn down the heat some. There are a number of "advanced" tricks a skilled welder can use to help fill joints and maintain the same machine settings. A lot of these "tricks" require that you can read the puddle and manipulate it well. It's not exactly something I can simply tell you to do X and you can replicate the same thing. It has to do with what you see and how you react to it more than anything else.One "trick" with mig would be to increase your stick out so you "cool" the puddle when needed. One problem with this is that you can easily make a cold weld at the edge and not get a good bond with the base material. Another "trick" would be to do a series of small "tacks" allowing the material to cool between each tack to build up the area. Again mig is notorious for cold starts, so you need to be able to come back and burn in all those cold spots when you weld up the area. Another one would be to weave back and forth between the two closing up the gap, but this really requires you have excellent puddle control or you will blow out the edge of the puddle and make your hole worse.Many times you use all of these and more, all at the same time to get the results you are looking for..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:I've used rod stubs to fill gaps. Just bust the flux off with a chipping hammer and lay the rod in there. Sometimes you have to tack it on one end. If the gap is 1/4 inch and you use a 7018 1/8 stub, be sure to run the "filler" from corner to opposite corner of the gap. Kinda diagonal. It gives more "filler" coverage. This isn't a procedure you would use in a test situation. It's dirty but fills the gap. When the gap is filled...be sure to run an extra hot cover pass. Thanks for reading!
Reply:Try a up side down u weave from one side to the other
Reply:I agree with DSW, improve your fit up and then you won't have to fill any voids.  However, there will be times you may need to fill a hole or make a repair where a gap is unavoidable.  Maybe this thought will help you visualize how you need to manipulate the puddle . . . you can't weld the gap . . . you weld the edges until the gap is filled.Dynasty 300DXSmith He/Ar gas mixerMM350PHobart Handler 120Smith LW7, MW5, AW1A
Reply:run a bead on each side, then go back and bridge across the gap, a technique called "buttering".
Reply:You can't magically conjure material to fill a gap, even with a wire feed.  Building up the edges to fill a gap will waste a lot of effort and give you a big blob in your project. Good practical welding is about making everything fit - putting as much as possible in the right place, in the first place, with planning, so that the welding is mostly an exercise in consistent seam sealing.  In art welding, anything goes, but in my experience, any gap such as you describe would need chunks of solid filler.  If it's linear, a length of filler rod, if wide or irregular, then maybe a strip of sheet or plate.  MIG is not all that flexible for dealing with this sort of creative problem, because you have a relatively unweildy gun and wire is always feeding.___________________________www.kevinwilbanks.comSmith AW series torch systemVictor 2-stage regulatorsWilbanks adjustable parrot vise standsHarbor Freight 6x48 belt sanderBeverly ShearMetabo, Bosch, Makita grinders
Reply:I think one of the first jobs which you might struggle with when your starting out as a welder is how to fill voids, gaps and holes.There may come a time where an over zealous operator has cut some material too short or plasma cut some shapes too narrow or even the guys in the machine shop drilling or punching holes in the wrong place.I can quite happily fill gaps of up 1/4 with welds holes upto 18mm (just over 1/2 inch) with welds.You just need to set your welder setting down and with holes  work one side until the hole is filled, then turn your set up and fill the other side, finally going back to the side you filled the center and weld that side, the idea is to have an appearance like a button weld both sides ready for sanding smooth.Filling in voids and gaps upto 1/4" needs a little bit more care, as if you attempt to weld one side first it will shrink as it cools and bend the piece. What you nee to do is to fill the gap up a little at a time all around, a series of tacks joining the top and bottom piece and do this on opposites until you have filled the void all round, Then turn your set up and make a nice fillet all around being  sure to include both pieces in the fillet.Next week, when i get a spare few moment i'll take some pictures and show you what i mean, its easier to show someone than trying to write about it
Reply:A lot depends on whether you're trying to fill a 1/4" gap in 1/2" steel or in 16 gauge steel. In other words on how thick the metal is. You simply can't let the metal around your weld get so hot it will deform. Which means on thin stuff you have to weld a little and then wait. Weld. Wait. Like that. I worked as a shipfitter for 13 years once. Fitting is actually a different trade than welding, although at home we all have to do both. There are many many tricks and techniques to fitting and if you want really outstanding results you really have to be able to use your brain a little. The first thing to master is can you cut a piece to length? I mean, if you need a piece 23-3/16" long and you mark it and cut it and measure it, how close is it to what you wanted? If you aren't real close every single time then you need to work on your techniques. It isn't easy to do precise cutting if you're using a gas ax, but it is possible. metalmagpie
Reply:Copper bar.... Put it under the joint, clamp it In place and burn the weld in and remove the bar.But I'd try and take better care of fitment. I understand it happens some times,.Miller bobcat 225g  - spoolmatic 1Mm250 - 30a spoolMiller spectrum 375Thermal arc 95 Everlast Ex 250As the boiler turns, these are the days of our lives