Reverse Polarity vs. Straight Polarity?

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Hey guys i just got my new welding machine today....  I went with the hobart Ac/Dc stick machine..... My question is.... I know the differnce and all, but i was just wonding yalls oppion on the pros and cons with reverse polarity vs. straight polarity.... So if yall would just give me some feedback id much apreciate it... Thanks...                                                                   John Deere
Reply:One of em is for hardfacing-or something like that, I forget been awhile since I had to stick."after a long day of doing nothing...its gooood to kick back" Pumbaa
Reply:http://www.sweethaven.com/academic/l...Num=7&modNum=3A true democracy is two wolves and a sheep voting on what's for lunch.
Reply:Crithpy,That's a great link.  Thanks.Be well.hankj
Reply:here's the whole showhttp://www.free-ed.net/fr02/lfc/0211...coursemain.aspA true democracy is two wolves and a sheep voting on what's for lunch.
Reply:Reverse polarity (D.C.+) = maximum penetrationA.C. = medium penetrationStraight polarity (D.C.-) = minimum penetrationI'll be the LAST one to let you down !
Reply:different rod are designed to work either ac/DCSP/DCRP some will work on all current setting some will only work on some of the current settings.  drcp will focuse the heat of the arc on the electrode making it easier to control the puddele, dcsp will but more heat on the work peice which will give you more penetration but will make more difficult to control whrn not working in the flat postion.
Reply:There are only a few rods that will run (or meant to be run) on straight polarity.  99% of the time you will run your rods on reverse (DC+) polarity.Here in the Great White NorthMosquitoes can't fly at 40 below
Reply:Originally posted by welder different rod are designed to work either ac/DCSP/DCRP some will work on all current setting some will only work on some of the current settings.  drcp will focuse the heat of the arc on the electrode making it easier to control the puddele, dcsp will but more heat on the work peice which will give you more penetration but will make more difficult to control whrn not working in the flat postion.
Reply:Gotta be Mac.DCRP IS high penetration. Straight is lower. That is unless you believe Richard Finch's masterpiece of welding literature!   We always used straight on sheet metal to minimize blow through. That is how I've always remembered which is which. Markopolo is spot on, too. Most mild steel rods can be used straight or reverse. Which to use would be based on application. Super strong or critical welds would be reverse polarity for penetration. Thin stuff doesn't need penetration as much since there isn't as much material to begin with.  6011 can go either way. Same with 6013.  6010 is reccomended reverse but will burn fine on sheet in straight. I can't forsee an application where 7018's would need straight polarity. That doesn't mean there isn't one.Hope this helpsDon
Reply:This can be a confusing issue to a lot of people.  "Welder" is 100% correct from a strictly electrophysics standpoint.  DCEN puts more of the heat into the work and DCEP concentrates the heat onto the electrode.  The problem arises in the fact that this only holds true if you are using GTAW or are stick welding with a bare electrode.  It does not take into account that penetration is greatly influenced by the plasma gases created by different flux coatings.  Markopolo and DDA52 are correct about 95% of the time when they state that in SMAW, DCEP gives deeper penetration.  You always have to go by what the manufacturer says concerning the use and characteristics of a particular electrode.  Most reverse polarity rods are designed to have the metal core melt faster that the flux coating.  This forms a cup like crater at the end of the electrode and the theory is that the molten metal and positive ions created in the arc plasma shoot across the arc with such force and attraction for the negatively charged workpiece that this is what causes you to get a more aggresive arc and deeper penetration.  Again, it depends on the flux coating, but most of the time in SMAW, reverse polarity will give you deeper penetration.  If you are TIG welding, then you will want to go with "Welder",  and get your deeper penetration with DCEN.   By the way, it is that same bombardment of positively charged ions in the plasma, being attracted to the negativlely charged work,  that breaks up the oxides when using AC GTAW to weld aluminum.
Reply:For stick welding guys should save themselves some anguish and debate,,, set the thing to DCEP and bust the knobs off so you dont fool with it again.www.urkafarms.com