Flux Cored VS Gas Shielded

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So I broke down and got a welder for home.  I want a 220V, but I currently live in an apartment with only a single set of standard household outlets in the garage.  If I had gotten the bigger welder, I would have had to run an extension cord from the dryer upstairs, out my kitchen window, and down to the garage ... every time I wanted to weld.   Since I'm gonna be in the apartment for a little while longer, I got the Lincoln 3200HD. I plan on doing sheet metal with the new welder right at the moment (obviously after a lot of practicing).To get to my question, I was reading the chart on the inside of the door and noticed that for gas shielded solid wire, you can't go as thick as you can if you're using flux cored wire.   This kinda ticked me off because I was anticipating setting this up for gas and being able to weld both  1/4" plate and sheet metal.  Maybe I'm not using the right search terms, but I was looking on here for some discussion on why flux cored welds thicker and what the Pros and Cons are of flux cored and gas shielded.  I had always heard that flux cored spattered a lot and gas shielded was a little better weld.   Correct me if I'm wrong.Thanks a ton.EDIT:Actually, I got to looking at this and see where it says gas shielded spatters less and makes a prettier bead.  But they indicate that solid wire can do thick metal, too.  What gives?http://www.millerwelds.com/education...tips/MIG_tips/Last edited by 98SS; 01-09-2007 at 08:32 AM.->Project Thread - 98SS BaggedAir Ride Questions Answered on AirRideTalk.com!!!DOT PTC FittingsDOT Compression FittingsAdaptersDOT Airline
Reply:Originally Posted by 98SSI got the Lincoln 3200HD. I plan on doing sheet metal with the new welder right at the moment (obviously after a lot of practicing).
Reply:Like most of life, there are trade-offs and limits.In general, flux-core wire runs 'hotter' than solid-core wire of the same size and can weld a little bit thicker materials.  The flip side is that solid-core wire runs a little 'cooler' and can weld slightly thinnner materials a little easier.  That and in the smaller size wires solid-core goes down to 0.023/0.025 wire and flux-core goes down to 0.030 and 0.035.Flux-core wire has, well, flux inside of it.  The burnt/melted flux is what makes the shield to protect the molten metal weld pool from the air during the welding process and it also makes slag.  Flux-core wire is essentially a stick electrode turned inside out, and flux makes slag.  Flux-core spatters more than GMAW (MIG welding), in general.Solid-core wire needs a shielding gas to protect the molten metal weld pool from the atmosphere.  It -can- produce cleaner and prettier welds than FCAW, with less spatter and no/minimal clean-up needed after welding.Next, wire is not just wire.  There are many different wire 'recipes', and they each have their limits and trade-offs as well.  You should look up the manufacturer's info on the wire regarding that wire's recommended uses and it's limits and trade-offs as well before using it.  One example is that Lincoln's NR-211-MP Innershield wire in 0.030, 0.035, and 0.045 is recommended for 5/16 inch plate MAX.Next, the material thickness limits also depend on the wire AND the machine.  The machine has its voltage and current (and current on a wire-feed welder is related to the wire-feed speed) performance and limits.And the door chart is not necessarily the absolute final word on setttings.  It is a general set of parameters that should get you close to do-able, but may or will have to be fine-tuned depending on operator skill and preferences and the specific physical joint characteristics being done (bevel, pre-heat, inside vs outside vs corner vs lap-joint, etc).Can 1/4 material be welded with a 3200HD welder?  Carefully, yes.  But the smaller 120V MIG welders are best on thinner stuff and sheet metal, that's where they really shine.  Thicker stuff generally needs more amps than the little guys can supply, and/or a thicker wire (which need more amps) to get enough heat into the work to get proper weld fusion across the joint.Can solid wire do thick stuff?  Sure, with a different machine and thicker wire than the little machines use and a different process (spray transfer instead of short-circuit transfer) it's quite easy.
Reply:Thanks guys.  That helps.   I'm gonna go ahead and set it up for gas for now, because pretty much all I'm gonna need to do in the near future is sheet metal anyway.  The bigger stuff I'll take to my friend who has a Miller 250DX TIG. He's getting me a bottle today, and I told him to go ahead and get the 75/25 mix.   He said the mixed gas will weld a tiny bit hotter than pure argon.Thanks again.->Project Thread - 98SS BaggedAir Ride Questions Answered on AirRideTalk.com!!!DOT PTC FittingsDOT Compression FittingsAdaptersDOT Airline
Reply:Oh, another set of trade-offs is in the gas used.Your 75/25 is a good general-purpose gas mix.A trade-off is to use 100% CO2 for a little more penetration and a little more spatter and less cost (note that a different regulator is usually needed for running straight CO2 than the argon/argon-mix regulator) on mild steel.  Running straight CO2 on thin sheet steel will make your life a bit more difficult, so an argon-CO2 blend is a better choice and standard 75/25 is just fine.Don't try to TIG (GTAW) with 75/25 though.  The result would be a toasted tungsten.Oh, and if you're just starting out with welding and GMAW, don't start your practice on the thin stuff.  Pick some 'medium' thickness practice pieces.  The thin stuff is easy to melt holes through pretty quickly, in addition to warping from the heat of welding.
Reply:98SS, take a look at the thread, "MIG Welds don't Stick".You will find a good comparison the challenges of using 117 VAC wire-feed welder and the loss of thickness capability when changing from flux-core to MIG welding.Rick V
Reply:I'll try and check out that thread soon.  Thanks.I laid down a couple beads last night on some 1/8".  I set it up with the 75/25 mix and the .025 solid wire that came with it.  My friend that I have been mentioning was there last night and he said he was kinda impressed with how well it did.   I'll get a couple pics up this evening.->Project Thread - 98SS BaggedAir Ride Questions Answered on AirRideTalk.com!!!DOT PTC FittingsDOT Compression FittingsAdaptersDOT Airline
Reply:98SS, take a look at the thread, "MIG Welds don't Stick".
Reply:Originally Posted by Rick V98SS, take a look at the thread, "MIG Welds don't Stick".You will find a good comparison the challenges of using 117 VAC wire-feed welder and the loss of thickness capability when changing from flux-core to MIG welding.