O/A - Second-pass welding

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For thick plate steel fillets, etc.  I've read mention of second-pass welding (have even seen illustrations) in books, but have never seen it demonstrated.I'd imagine that you have to take care that the two pieces of plate being joined melt (puddle), as well as the first bead that you previously laid down.  Any other considerations or tips?One other question occurs to me: cleaning up.  Is there any advantage or disadvantage to grinding or wire-brushing the first bead plus the edge surfaces of the fillet (the "parent metal") before laying down the second bead?Thanks.
Reply:Cleaning is always an important step before putting down any bead. And before putting a second bead, it is just as important. This holds true for any process, but it is imperative with tig (GTAW), and mig (GMAW). I don't know if you meant to say that you are using oxyacetylene to weld these, but cleaning will always help. The code book says to clean everything within 2 inches of a weld zone.City of L.A. Structural; Manual & Semi-Automatic;"Surely there is a mine for silver, and a place where gold is refined. Iron is taken from the earth, and copper is smelted from ore."Job 28:1,2Lincoln, Miller, Victor & ISV BibleDanny
Reply:Joel, a second pass is also refered to as a hot pass and basically is just a second bead in the groove before you start building the joint with succesive passes to fill the groove.  A second pass is usually a harder rod like a 7018 behind the root pass with a 60xx.  It is supposed to give additional strength to the joint prior to build up and capping.  All slag must be cleaned between all passes to prevent an inclusion from screwing up your work.  Slag in a weld is a definate No-No.  If you go to Millerwelds and search Multi-pass they have an excellent drawing there that illustrates the concept and designates all of the elements in that weld.I'm spending my Kids inheritance, I dont like him that much anyway!!!!!!Enuff tools to do the job, enough sense to use em.Anybody got a spare set of kidneys?  Trade?
Reply:Originally Posted by RbeckettJoel, a second pass is also refered to as a hot pass and basically is just a second bead in the groove before you start building the joint with succesive passes to fill the groove.  A second pass is usually a harder rod like a 7018 behind the root pass with a 60xx.  It is supposed to give additional strength to the joint prior to build up and capping.  All slag must be cleaned between all passes to prevent an inclusion from screwing up your work.  Slag in a weld is a definate No-No.  If you go to Millerwelds and search Multi-pass they have an excellent drawing there that illustrates the concept and designates all of the elements in that weld.
Reply:Your right I miss read the OP.  I thought he was talking about stick or elec welding.  Sorry.I'm spending my Kids inheritance, I dont like him that much anyway!!!!!!Enuff tools to do the job, enough sense to use em.Anybody got a spare set of kidneys?  Trade?