FCAW (Dual shield)

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Started FCAW this term. First up is dual shield. 1F on 1/2" mild steel. 1/2" (3 passes) deposited. I have another layer to do before the assignment is finished. Quick and smooth. I love how easy the slag comes off, too. A heck of a lot better than 7024 and 7018.Do what it takes to get the job done right.
Reply:Dual shield is nice . I am still trying to get it down for some reason I kept on getting porosity until I turned the gas flow way up.
Reply:on the 71C we run here at the shop the CO2 flow is 45 CFHVantage 500's LN-25's, VI-400's, cobramatics, Miller migs, synch 350 LX, Powcon inverters, XMT's, 250 Ton Acurrpress 12' brake, 1/4" 10' Atlantic shear,Koikie plasma table W/ esab plasmas. marvel & hyd-mech saws, pirrana & metal muncher punches.
Reply:45cfh is what they have us running for these assignments. We're using E71T-1 electrode wire also.I ran those welds at 24 volts and around 200 wfs.Do what it takes to get the job done right.
Reply:I run about 30 cfh for the t1 stuff. As far as getting any porosity, it may be your stickout. You need quite a bit more stickout then hard wire to make sure the flux gets warmed up and has time to do its job or it can get trapped and gas out of the puddle. Dual shield is fun and fast. Like zen welding.Millermatic 252Lincoln 175 plusTA 185tswTA 161stlhypertherm pmax 45Victor torchHenrob torchAn S10 for each day of the week
Reply:Ok that makes sense at first my gas flow was around 25 cfh after turning it p to around 40 cfh it went away. I will try to use longer stick out also. Thanks.
Reply:Originally Posted by S obsessedI run about 30 cfh for the t1 stuff. As far as getting any porosity, it may be your stickout. You need quite a bit more stickout then hard wire to make sure the flux gets warmed up and has time to do its job or it can get trapped and gas out of the puddle. Dual shield is fun and fast. Like zen welding.
Reply:Maybe it is just me but the edges of your beads seem not straight like you are having speed problems or something.  The edge of your passes should be straighter.  That flux core is dead easy to use on flat and horizontal.  It seems to me it is something like running without quite enough heat of maybe a smidgen more voltage is needed to make the puddle more fluid.  Maybe a circular motion or slight weave? I mostly run metal core so I can't say positve.  the beads look good enough for school. ... but then if you want to get a really good mark...  :')
Reply:Originally Posted by lotechmanMaybe it is just me but the edges of your beads seem not straight like you are having speed problems or something.  The edge of your passes should be straighter.  That flux core is dead easy to use on flat and horizontal.  It seems to me it is something like running without quite enough heat of maybe a smidgen more voltage is needed to make the puddle more fluid.  Maybe a circular motion or slight weave? I mostly run metal core so I can't say positve.  the beads look good enough for school. ... but then if you want to get a really good mark...  :')
Reply:With slag you drag.  Just a little motion should wash the puddle into the edges better I think.   Had a lecture on how to stand?  Standing on two legs with helmet down is like a pilot trying to fly a plane in the fog.  You have no horizontal/vertical reference.  Lean against something or set one leg up like on a bar stool and lock your body.  Once your body is locked then the only muscle groups your brain has to deal with are your arms and hands.  When you stand free your nervous system has to monitor and control your legs as well as your arms.  That is extra work and you fatigue sooner.
Reply:Ha, that's a cool rhyme. I usually drag with 7024 and 7018 and drag on 6011. One of my teachers prefers dragging on dual shield and another prefers push. They told me either will be good and, if you do them correctly, will give you quality welds. I was leaning against a pole with my helmet, so, I was pretty steady, just not steady enough. I think I might have had my arms extended too far. Next time I'll be closer to the work and make sure that I lock myself down.Do what it takes to get the job done right.
Reply:Deffinitely pull that stuff. I use 1/2" stick out at most. I rest my nozzle on the work and pull the nozzle/gun. You should be able to get perfectly straight and smooth welds. It just takes practice. deffinitely get stable and smooth, but try resting your nozzle on your work and drag it slowly and smoothly. Keep the same speed and you will get a very nice weld. Hope that  helps, doug.
Reply:I'll give it a try tomorrow and take a few more pictures. I have one more layer to go on that 1f t-joint before I need to turn it in. Next up is a 2f t-joint.Do what it takes to get the job done right.
Reply:With FCAW you want to be careful with a push technique. You're more likely to trap slag on a fillet weld or root pass. If you're putting down you're cap passes pushing would help to keep a flat profile.  Even when dragging you want to keep in mind to keep the wire at the leading edge of the puddle. Keep a faster travel speed up to insure good penetration.CAW/MWF Local 1Halifax Shipyard
Reply:I've always wanted to give Dual-Shield a try. It looks like it lays down some very nice welds. I've welded with gasless 0.035 flux-core and I've MIGed with 75/25 and solid 0.035" wire with great results. I've always wanted to give Dual-Shielded wire a try. I'm still fairly new at welding, I've been welding(MIG/Flux-core) for quite a few years, but I've still got A LOT to learn yet. What are some of the advantages of Dual-Shield over say gasless flux-core or solid wire with 75/25?Brad GeorgeCurrent Equipment:AIRCO Heliwelder IV 300Amp Model - Total Awesomeness!Old 120v Hobart Handler MIGVarious grinders, cutting tools, hammers, clamps, ect..."I'm an amateur welder with lots left to learn..."
Reply:I've never used the gasless  flux-core, but the dual shield gives a weld similar to 7018 as far as strength and ductility.It's mainly what I use for fab on anything over 1/8", under that I use the solid .035" indoors. Everything else gets 6010 and 7018. I use 75/25 gas for the dual shield and solid.Leo
Reply:Originally Posted by blasphemy000I've always wanted to give Dual-Shield a try. It looks like it lays down some very nice welds. I've welded with gasless 0.035 flux-core and I've MIGed with 75/25 and solid 0.035" wire with great results. I've always wanted to give Dual-Shielded wire a try. I'm still fairly new at welding, I've been welding(MIG/Flux-core) for quite a few years, but I've still got A LOT to learn yet. What are some of the advantages of Dual-Shield over say gasless flux-core or solid wire with 75/25?