Welding Noob - Welded 1/2 plate. How'd I do?

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Okay, so I figured I'd take up welding as a hobby. I'm a bit of a procrastinator though.I bought a Lincoln PowerMIG 180C like last year. Or maybe it was a couple of years ago. I can't remember. I've done little mending projects here and there. But I'm doing more stuff now.Some of the projects I have lined up are:Grinder Stand using 1/2" plate for the foot, 4x4 column, and 1/4" plate for the topGo Kart projectSo, I started work on the Grinder Stand. I had 2 pieces of 1/2 inch plate that I needed to butt weld together to make it a larger foot.I grounded the edges and I grinded a bit of chamfer at the joint so the weld can go deeper inside the joint.Anyway, I welded both sides of the plate. Here are pictures. I did a continuous line on the first side, but it got so hot that it bowed. You'll notice that in the pictures that I have attached.What should I do next time so that it doesn't bow/bend like that? I'm sure it just got way too hot.I think the second side came out better (last two pictures). The first side I was doing "little C's" the second side I was doing "little circles" as I moved the torch.Thanks!Joey Attached Images
Reply:Looks fine for what you are doing. You need to work more on your stop / starts in the 1st pict as well as your consistency of movement.As far as warping, you need to understand why the material is going to warp, and then work to counter it in advance. Even when you do everything right, chances are it may still warp if the conditions are right. Keep in mind many times steel, especially plate which comes in rolls, may have residual stresses in the material. As soon as you heat the material, those stresses will want to rearrange the steel in ways it can some times be hard to predict.Lots of weld and heat on one side tends to want to pull the metal towards the bead. You can counter this by adding a bit of positive angle to the material so it will pull straight. Tacking things up in the right order can also help. That way things are less likely to move. While you need "heat" to get good penetration, some times too much heat can cause you issues as well. There's a fine line between too little heat and too much in some cases. You learn this thru experience. In some things you take the risk that too much heat and the warpage you get is the sacrifice you have to make to make sure you get good penetration. On other things where strength is less important, minimizing warpage may be of greater importance, so you run with less heat..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 DSWLooks fine for what you are doing. You need to work more on your stop / starts in the 1st pict as well as your consistency of movement.As far as warping, you need to understand why the material is going to warp, and then work to counter it in advance. Even when you do everything right, chances are it may still warp if the conditions are right. Keep in mind many times steel, especially plate which comes in rolls, may have residual stresses in the material. As soon as you heat the material, those stresses will want to rearrange the steel in ways it can some times be hard to predict.Lots of weld and heat on one side tends to want to pull the metal towards the bead. You can counter this by adding a bit of positive angle to the material so it will pull straight. Tacking things up in the right order can also help. That way things are less likely to move. While you need "heat" to get good penetration, some times too much heat can cause you issues as well. There's a fine line between too little heat and too much in some cases. You learn this thru experience. In some things you take the risk that too much heat and the warpage you get is the sacrifice you have to make to make sure you get good penetration. On other things where strength is less important, minimizing warpage may be of greater importance, so you run with less heat.
Reply:Ummm, a 180-class machine and short-circuit transfer-mode GMAW on 1/2 inch thick steel plate?  No matter how many passes you do, short-circuit transfer with even 0.035 solid wire just does not have enough energy ('heat') to fuse into 1/2 inch thick steel plate. That thickness of plate is in the realm of spray transfer or SMAW (which is pretty much a 'type' of spray transfer) or maybe (just a maybe on that) some 0.045 FCAW wire.  But not Lincoln NR211-MP, as that has a workpiece thickness limitation of 5/16 inch thick plate MAX with 0.045 and smaller wires (0.068 and larger wires raise the workpiece thickness limit to 1/2 inch thick max, but that won't be be a wire size you'd ever run through a 180-class machine).  NR-212 has a workpiece thickness limit of 3/4 inch thick max.Grinding the joint edges to get a V or U shape is common on 'thicker' materials, so that the electrode can physically reach the "root" area of the joint in order to get the arc and electrode and filler metal 'down there'.  But even that joint prep does not get around the physics that 1/2 plate is rather thick for the amount of energy that a 180-class machine can put into the arc.  Not enough arc energy for the thickness of material being welded = "lack of fusion" aka "cold lap" aka "inadequate penetration".  Classic problem with MIG aka GMAW, the weld looks OK, but didn't penetrate/fuse into the base material worth a darn.  The weld is just sitting on top of the parent material.The arc has to melt -into- that base/parent material and then the filler has to 'fill in' the joint, so that the weld has achived a state of Zen beingness.    You have to get the parent material and the filler to all melt together and turn into one 'lump' of metal.  Multi-pass SMAW on some 1/2 inch thick steel plate?  Sure.Multi-pass short-circuit transfer-mode GMAW with a 180-class machine on some 1/2 inch thick steel plate? Nope.  Right from Lincoln's product 'spec' / sales sheet on the PM180C, 0.035 solid GMAW tops out at a 'rated' 3/16 inch thick.  For 1/2 inch thick steel, the sheet says multi-pass with 0.045 NR-212 FCAW.http://assets.lincolnelectric.com/as...473-1/e724.pdfSolid-wire GMAW on 1/2 inch thick steel is in the realm of the 'big-boy' PM256 (current model number) or similar machines than can do spray transfer GMAW.  The best laid schemes ... Gang oft agley ...
Reply:I totally agree with you MoonRise and I do understand what you're saying.I know my little machine isn't up to the job at REALLY welding those two pieces together. Rest assured, I wouldn't use my machine to do this kind of job if I was building something where safety was an issue.I just wanted to get these two pieces "glued" together for the base of a Grinder Stand. I used 1/2" plate because I wanted the base to be sturdy and heavy. Also, that's what I found at the local steel supply (BobCo in Los Angeles).I really do appreciate the word of warning though. That's how I learn.By the way, I did use .035 flux-cored wire since I'm out of gas. Not that it matters that much since my 180 still is a small machine.Thanks for the input!Joey G.
Reply:There are all sorts of ways to straighten plate. You could do it cold with a big enough press.  I've bent things back using heavy equipment to "lean" on things or in some cases hydraulic jacks if you can find something strong enough to push on. You usually need to bend well past straight to do this and you need to be careful when applying lots of pressure. You could also heat it up with an OA torch and then straighten it several ways.Moonrise is right about your machine not having enough output for 1/2" material to make code quality welds.  That doesn't mean you can't use the machine for some uses with thicker material however. That's why I said for what you were doing it was fine. All you really needed to do was hold the two pieces together like "glue".A couple things to think about. Flat plates don't make the best bases. Any floor irregularity will cause it to rock and not sit flat.  That's why most bases either have feet or have limited contact surfaces. Some thing as simple as 3 or 4 washers tacked to the bottom might be enough to let this sit "flat" and deal with small irregularities in a smooth floor. On a rougher surface maybe some leveling legs made up of some bolts in threaded holes..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:DSW - you make a good point about the irregularities of the floor.The threaded holes and bolts idea seems pretty doable. The plate is thick enough to probably tap threads into it. Add some bolts and a lock nut and I should be good to go.Originally, I did think about bolting this thing to the floor, but being able to move it would be nice.Joey G.Downey, CALincoln PowerMIG 180C
Reply:Make it with 3 legs instead of 4 and it won't rock
Reply:As far as bending the base, you don't need to if you just weld something under it to make it solid.Welder- Miller Thunderbolt AC 225-DC 150 Plasma cutter, Miller Spectrum 300O/P torch- Victor 100
Reply:You can tap the base plate and then use bolts. Instead of a lock washer, use a nut under the bolt head. When you adjust the bolt to level every thing out, then tighten the nut against the plate to lock it and it will not move. You can put the bolt head down and tighten every thing from underneath, or put the head up and use the threaded end on the floor. It's easier to adjust and lock that way. If you go with the top of the bolt sticking up, you probably want to grind the last few threads off so if they get dragged on the floor they won't get messed up. Then clean up the threads with a die or back off a nut you already installed to straighten out the threads. They sell specialty leveling legs for this use as well if you want to go that route..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:One shop I worked in, the pedestal grinder base was welded to a heavy old presumably sawmill oriented sprocket!  Let me tell you, that was the best dang, silent and sturdy pedestal grinder I've ever used!  If you left it on by accident, you wouldn't even hear it whirring away.
Reply:Heck - no need for extra feet.  Just put the arch facing the floor, and tell people you did it on purpose so it would sit on the 4 corners -DaveXMT304 with: 22A Feeder, or HF251 Hi Freq DC TIG air cooled
Reply:save the plate for a nother project and make a 3legged base or weld it to a truckrim...
Reply:Originally Posted by davecHeck - no need for extra feet.  Just put the arch facing the floor, and tell people you did it on purpose so it would sit on the 4 corners
Reply:If you not want to tap the hole you can through drill the holes and use full thread bolts with nuts above and below the plate. Also a piece of rubber mat under the plate! can keep it from movingMillermatic 252millermatic 175miller 300 Thunderboltlincoln ranger 250smith torcheslots of bfh'sIf it dont fit get a bigger hammer
Reply:I would save the drama if u don't need anything special and get the hf grinder stand http://www.harborfreight.com/bench-g...and-42986.html fill the tube with concrete and u gtgLast edited by Malave16; 01-14-2012 at 10:16 PM.
Reply:Originally Posted by Malave16I would save the drama if u don't need anything special and get the hf grinder stand http://www.harborfreight.com/bench-g...and-42986.html fill the tube with concrete and u gtg
Reply:On picture #2, you can still see the joint prep for the butt weld. As you can see it didn't burn in. Will be fine for your intended use though.You could have also put more of a bevel on the plates. Next time try about about a 40 degree bevel on each plate, and leave a gap in between them of about 1/8". Might need to use a backing strip of some sort though. Copper should work, find some copper tubing and cut lengthwise through the wall, then upon it up and beat it flat. One way to minimize distortion while welding is to "clamp down" the pieces to be joined. Use C-clamps or something similar. However, once welding is done and clamps are removed, the material will still have a tendency to "spring", but it won't deflect as much.Miller Bobcat 225Miller Diversion 180 - sold searching for a DynastyHobart TigmateMillermatic Challenger 172
Reply:Originally Posted by gcnettlOn picture #2, you can still see the joint prep for the butt weld. As you can see it didn't burn in. Will be fine for your intended use though.You could have also put more of a bevel on the plates. Next time try about about a 40 degree bevel on each plate, and leave a gap in between them of about 1/8". Might need to use a backing strip of some sort though. Copper should work, find some copper tubing and cut lengthwise through the wall, then upon it up and beat it flat. One way to minimize distortion while welding is to "clamp down" the pieces to be joined. Use C-clamps or something similar. However, once welding is done and clamps are removed, the material will still have a tendency to "spring", but it won't deflect as much.
Reply:to prevent to much buildup on the backside and/or to prevent welding it to table top.225NT bobcatAEAD200LEScott 125mm175, mm252 w 30A, PT225mm211, TA 181iHyper Therm 380, cut master 529100X & XX, Digital Elite6 Victor setssmith little torch, meco midget kalamazoo band sawsteel max saw evoulution circular saw
Reply:Originally Posted by jbmprodsto prevent to much buildup on the backside and/or to prevent welding it to table top.