DCEN or DCEP ????

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Help me figure out which is which.  Obviously "Electrode Positive" and "Electrode Negative" are self explanatory, but I'm having a little difficulty determining which has which characteristics.  Getting ready do a little welding (SMAW) and it's been a while and I';m pretty low on experience anyway, so I thought I'd review the basics.  Went to the local library and was thumbing though their collection of welding books.  Out of 4 books, 2 say that DCEP has greater penetration and slower rod burn than DCEP and the other two books say the opposite.  I thought I must have misread, so I opened all 4 books to the relevant pages and compared directly.  Sure enough, 2 were saying the exact opposite of the other two.  3 are fairly thick, detailed, technical seeming books and the fourth, is a "here's how to weld" type aimed at hobbyists.   So which do I believe?
Reply:A quick google search came up with this:http://www.hobartwelders.com/weldtal...ead.php?t=6196Depends on the process...consumable or non-consumable electrode.Hobart Handler 140Everlast PowerMTS 200SHypertherm Powermax30
Reply:Originally Posted by Thumper99A quick google search came up with this:http://www.hobartwelders.com/weldtal...ead.php?t=6196Depends on the process...consumable or non-consumable electrode.
Reply:try it each way  at several different amp settings, with several different rod types,  and you will know the answer. should take you ten minutes.
Reply:I'm sure someone else could explain it better, but it's to do with the flow of electrons, DCEN puts more heat into the work piece and DCEP puts more heat into the electrode. Different processes require different things, generally with a non consumable electrode it is desireable to have more heat in the work piece and with a consumable electrode the opposite.
Reply:For most SMAW using DC, I think you'll find that you want to use EP.Once in a while, when welding real thin stuff for example, you might want to switch to EN.
Reply:some rods will only run on certain polarities properlyMiller Xmt 350Lincoln Ln-25Ahp 200xSmith Gas Mixer AR/HTig is my Kung FuThrowing down dimes and weaving aboutInstagram http://instagram.com/[email protected]
Reply:Originally Posted by A SquaredI opened all 4 books to the relevant pages and compared directly.  Sure enough, 2 were saying the exact opposite of the other two.
Reply:Yep called Electron flow theory........  Miller Dynasty 350Twenty Six HammersThree Crow BarsBig Rock
Reply:With GTAW/DCEN, the flow of electrons from the electrode to the work, and the impact of the electrons with the work, produces the majority of the heating to produce the weld.  If you've ever tried GTAW/DCEP, you know that the majority of the heat occurs at the electrode.With SMAW, DCEP puts the majority of the heating into melting the electrode, the molten electode is then propelled to the work and very efficently transfers the heat to the work, producing greater melting than DCEN.  SMAW with DCEN can be used for low penetration applications such as a welding sheet stock or applying a surface cladding where you don't want to dilute the filler by melting to much base metal.GMAW is similar to SMAW in how polarity works with heat transfer.With FCAW, I have to say I am guessing and have not taken the time to research the physics, but as I understand it the self shielded wire is designed to operate DCEN, apparenty having something to do with generating shield gas from the flux core, and the gas shielded FCAW wire operates like GMAW, with more heating to the work with DCEP.  Here's one reference that mentions FCAW polarity.  http://www.thefabricator.com/article...nders-requiredLast edited by pulser; 03-17-2011 at 11:18 PM.Reason: added reference
Reply:Hmmmmmmmm interesting, I have never used DCEP for anything other than "Balling " the tungsten.........What would you use that setting for?  Miller Dynasty 350Twenty Six HammersThree Crow BarsBig Rock
Reply:Originally Posted by KelvinI suspect you're reading about two different processes – SMAW (stick) and GTAW (TIG).
Reply:Just go to https://www.awspubs.com/product_info...roducts_id=270It is a Pocket handbook about 1/4 inch thick and will fit in your pocket.Choose the printed HARD COPY.#7 in the series. They are plastic coated and spiral bound for hard use.It tells you everything you need to know all in one little book.It is sad but these little handbooks used to be for sale, or free in every welding supply store.Now you see NO book or pocket guide books in the welding stores VERY SAD.The American Welding Society a welders best friend.One more thing.... On the outside of the box of electrodes, the information on the box that most people do not read usually tells you of the rod is DCEP or DCEN  " prefered."Last edited by Donald Branscom; 03-20-2011 at 04:03 PM.Reason: spellingAWS certified welding inspectorAWS certified welder
Reply:Here is one of the books I have and I have had it since I was 16 years old.HOBART WELDING GUIDE (pocket size) 4 inch x 7 inchhttp://cgi.ebay.com/Welder's-Bible%3...QQcmdZViewItemOnly 3 left as of today March 20th 2011.AWS certified welding inspectorAWS certified welder
Reply:Originally Posted by B_CHmmmmmmmm interesting, I have never used DCEP for anything other than "Balling " the tungsten.........What would you use that setting for?
Reply:Wow 1/4 "  tungsten.......Hmmmmmmm  I bet a pack of that would set you back a few bucks...  Miller Dynasty 350Twenty Six HammersThree Crow BarsBig Rock
Reply:I think I remember seeing a pack of 1/4's for around $3-400. I look at 1/8" and it looks like a small tree. Even 3/32 looks big to me after using 1/16 and smaller for a while