Why is a grounded workpiece called "Reverse Polarity"?

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Probably a stupid question, but this bothers me. Normally, I ground the workpiece and attack it with the electrode. So normal = reverse?(Let's ignore the fact that I only have an AC welder for a second...)It just seems like one would logically think that the workpiece would "normally" be grounded, not hot, and the active part you are using would be the hot part. So calling the reverse of that "reverse" doesn't make much sense to me.Anyway, I guess I could live be being told that it's just that way, but I just read something else...I just read that the reason Reverse Polarity means a hot electrode is because electrons flow from the ground to (+). This is what actually bothers me: No other engineering discipline in the world uses that convention. We all know it's true, but EVERY SINGLE OTHER FIELD uses a system that follows "hole flow". Even electrical schematics indicate diodes with arrows indicating the flow of positive current. Please, someone tell me that the weldors didn't decide to just be different from everyone else. Please tell me that there is no real reason behind the Reverse designation. Or maybe the first welding machines only did Straight polarity, and so they later designated EP as reverse. But please don't tell me that unlike every other mechanical or physics field, they decided to base welding on the direction of electrons."To tell which polarity to use go to the bathroom and pour some water down the drain. If it runs clockwise use straight polarity. If it runs counter-clockwise use reverse polarity. Or if it just gurgles use alternating current." -RandomDave
Reply:Electrons flow from "negative" to "positive" ...if I remember electrical theory correctly!therefore, "normal" flow would be from your tungsten (tig) or your electrode (stick) into your workpiece.  The electrons would be flowing from the torch into the workpiece....from negative to positve (electrode negative).....or straight polarity.I think what makes it "wierd" is because of the use of a "ground clamp."  We always think of a "ground" as being negative.  So, visually, you see your ground clamp, and you naturally think of it as the "negative" in the system.
Reply:BurningMetal hit the nail on the head Skippii.  At least you were willing to ask in an effort to understand.  Try explaining it to someone (a seasoned weldor) who refuses to accept basic electrical facts.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!
Reply:skippii,If you remember from basic electrical classes:Conventional flow is from Positive to Negative.Electron flow is from Negative to Positive.Let's blame this confusion on Benjamin Franklin.  He described flow from a positive source to a negative source.  It wasn't until years later after technological advances lead to the discovery of the electron that it was proved that electron flow is from negative to positive.  However, by that point, tradition was already firmly established (even though it was wrong).  Like BurningMetal said, just because it's called a ground clamp, doesn't necessarily mean it is negative.In the case of MIG, the gun is DCEP (Direct Current Electrode Positive) and the ground clamp is negative. In the case of Fluxcore (same machine reversed leads on the inside), the gun is DCEN (Direct Current Electrode Negative) and the ground clamp positive.  So you see, in this example positive and negative can change based on the weld process (MIG vs. Fluxcore) and internal lead arrangement.
Reply:Actually, straight and reverse polarity have nothing to do with electron flow.The names came about from bare wire welding and carbon rod welding. Both are run electrode negative. Bare wire because it is darn near impossible to control otherwise, carbon rod because the carbon spits and contaminates the weld if run electrode positive.Ref: 1938 Hobart Arc Welding Handbook;  Machinerys ref series vol 127 (http://books.google.com/books/downlo...Mdx5CnJs2tDpJA See page 4: Bernardos process)
Reply:Reverse Polarity= Rod Positive the to RP's go together, that's the way it is and I quit trying to explain it and confuse everything once I graduated.Tough as nails and damn near as smart
Reply:Originally Posted by enlpckActually, straight and reverse polarity have nothing to do with electron flow.
Reply:Originally Posted by tresiReverse Polarity= Rod Positive the to RP's go together, that's the way it is and I quit trying to explain it and confuse everything once I graduated.
Reply:Skippii, Skippii, Skippii, Skippii, stop thinking so much, stay in bed another hour.The term, “Ground” is thrown around with every change of the wind. The “ground” clamp doesn’t ground anything. The clamp and the wire attached to it is the current return path to the secondary coil in the transformer and NOTHING MORE. Transformer OUT>welding cable>rod clamp>rod>arc>work>GROUND CLAMP>welding cable>transformer IN, all forming a closed loop. Don’t believe me? Check for continuity from the GROUND pin on the power plug to the “GROUND” clamp.
Reply:This should have stopped at Burning Metal's explanation. If I read anymore, I will stab my eyes.UA Local 598
Reply:Holy Crap.... WAY too many people trying to sound like rocket scientists - And NO, it's NOT working.... LOLMight be easier to replace "Ground" with "Work Lead".... Just to sort your brain out.So you have the Elecrode, and the Work Lead....Whatever is "Positive" will be the hotter of the two...Straight Polarity - DC Electrode NEGATIVE - Work Lead (Work piece) will be "Hotter" than Electrode.Reverse Polarity - DC Electrode POSITIVE - Electrode will be "Hotter" than Work Lead (Work piece)As to the Specific Scientific Explanation - WHO CARES? - In the end, I just need to know how to hook up my cables to get the job done.Don't make Welding harder than it needs to be fellas.Last edited by Black Wolf; 03-06-2010 at 10:17 AM.Later,Jason
Reply:I generally stay away from referring to specific processes for the exact reason that was demonstrated in a previous post - The member claimed that GMAW (Mig) is Electrode Positive, wile FCAW (Flux Core) is Electrode Negative....This Information, while well intended by the member, is FALSE.FCAW(Flux Core) Dual Shield (With Gas)  is Normally Electrode Positive same as GMAW.FCAW(Flux Core) Self Shield (No Gas) is Normally Electrode Negative, the opposite to GMAWDon't take MY, or ANYONE'S word for it, read the Manufacturer's Recommendations on the product packaging.Later,Jason
Reply:Originally Posted by Black WolfThis Information, while well intended by the member, is FALSE.FCAW(Flux Core) Dual Shield (With Gas)  is Normally Electrode Positive same as GMAW.FCAW(Flux Core) Self Shield (No Gas) is Normally Electrode Negative, the opposite to GMAWDon't take MY, or ANYONE'S word for it, read the Manufacturer's Recommendations on the product packaging.
Reply:No Worries Boss...I wasn't meaning to single you out, or pick on you for it.... But it is very, VERY, easy to make small mental mistakes like that when we are explaining things to others.I am aware that you know what you are talking about on this topic, and know what you intended, but when typed in that form as an "Absolute" it is incorrect, and misleading.Have a Good Day.Later,Jason
Reply:lol.....this thread is still rolling!  I try to avoid talking "reverse/straight polarity" when talking to other welders.  It is easier and more straight forward to speak of the electrode (or torch) polarity. ....... either EN or EP.  then, there's no confusion.
Reply:I try to avoid talking to other welders, OR co-workers for that matter!I like to hook up the Air Arc and send 'em ALL running away SCREAMING!ROFLMAOHave a Good Day.Later,Jason
Reply:For an easy way to tell which polarity to use go to the bathroom and pour some water down the drain.  If it runs down the drain clockwise use straight polarity.  If it runs counter-clockwise use reverse polarity.  Or if it just gurgles use alternating current.
Reply:Because that is the way the electrical gods made it.Disclaimer; "I am just an a$$hole welder, don't take it personally ."
Reply:This has been very entertaining......zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Originally Posted by RandomDaveFor an easy way to tell which polarity to use go to the bathroom and pour some water down the drain.  If it runs down the drain clockwise use straight polarity.  If it runs counter-clockwise use reverse polarity.  Or if it just gurgles use alternating current.
Reply:Originally Posted by enlpckThe names came about from bare wire welding and carbon rod welding. Both are run electrode negative. Bare wire because it is darn near impossible to control otherwise, carbon rod because the carbon spits and contaminates the weld if run electrode positive.Ref: 1938 Hobart Arc Welding Handbook;  Machinerys ref series vol 127 (http://books.google.com/books/downlo...Mdx5CnJs2tDpJA See page 4: Bernardos process)
Reply:where's mc cormick with a polarized lightning strike story ?
Reply:I think I saw this here, back in the day rods were typically dcen so on welders the stinger was always on the "neg" or - and the work clamp was on the "pos" or + , with newer technology and improved rods and coatings they started making the rods run off of dcep so you would reverse the cables hence the name reverse polarity, I could be wrong though so don't take my word for it  hahahaha"Obstacles are those frightful things you see when you take your eyes off your goal"   -Henry Ford
Reply:Originally Posted by RandomDaveFor an easy way to tell which polarity to use go to the bathroom and pour some water down the drain.  If it runs down the drain clockwise use straight polarity.  If it runs counter-clockwise use reverse polarity.  Or if it just gurgles use alternating current.
Reply:Originally Posted by enlpckActually, straight and reverse polarity have nothing to do with electron flow.The names came about from bare wire welding and carbon rod welding. Both are run electrode negative. Bare wire because it is darn near impossible to control otherwise, carbon rod because the carbon spits and contaminates the weld if run electrode positive.Ref: 1938 Hobart Arc Welding Handbook;  Machinerys ref series vol 127 (http://books.google.com/books/downlo...Mdx5CnJs2tDpJA See page 4: Bernardos process)