Any advice for arc gouging on cv?

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Hey guys, in my shop we have an older 600amp Lincoln transformer (I think an rd35? I,ll confirm tomorrow) we have set up as our air arc rig. There are times when having 2 setups would greatly expedite work, so I am looking for a way to set the miller delta weld 652 I use to weld with to quickly switch to gouging. However I heard there are concerns when gouging on cv, something to do with the voltage spiking and embedding bits of the carbon electrode into the work? I've looked at the manual for this machine online and all it really says is it is capable of the air arcing without going into detail of set up or anything.If its as easy as hooking up a gouging stinger and striking an arc does anyone have recommended settings? Cranking the voltage to the max could be a fun experiment... Looking forward to your input!
Reply:on CV, you can "dig" in the base metal, whereas on CC you get a more uniform penetration depth.other than that, both ways seems to work just fine.
Reply:Do a search, there is a link to the Arcair user manual. It will explain the process in CV mode."Where's Stick man????????" - 7A749"SHHHHHH!! I sent him over to snag that MIC-4 while tbone wasn't looking!" - duaneb55"I have bought a few of Tbone's things unlike Stick-Man who helps himself" - TozziWelding"Stick-man"
Reply:Originally Posted by JoedanHey guys, in my shop we have an older 600amp Lincoln transformer (I think an rd35? I,ll confirm tomorrow) we have set up as our air arc rig. There are times when having 2 setups would greatly expedite work, so I am looking for a way to set the miller delta weld 652 I use to weld with to quickly switch to gouging. However I heard there are concerns when gouging on cv, something to do with the voltage spiking and embedding bits of the carbon electrode into the work? I've looked at the manual for this machine online and all it really says is it is capable of the air arcing without going into detail of set up or anything.If its as easy as hooking up a gouging stinger and striking an arc does anyone have recommended settings? Cranking the voltage to the max could be a fun experiment... Looking forward to your input!
Reply:I was doing a writing project and queried ArcAir directly by email.  A rep phoned me back personally and urged me not to recommend CV for gouging.  Yes you get less "sticking or erratic arcs" but the amperage spikes drive carbon particles into the parent metal.  This is no big deal until you weld over the surface and end up with a weld bead with higher than normal carbon content which makes for a less ductile metal and a failed bend test.   If you gouge with CV you will not see a "bad" weld afterward.  The cracking is likely to show itself while in service.  I have seen people come in to do a challenge test where they back gouged with CV.  The bend test failed and the instructors were scratching their heads wondering why the failure when the guy doing the test seemed to be perfectly capable of passing.
Reply:A little info. on CV page 27.http://victortechnologies.com/IM_Upl...August2013.pdf
Reply:Interesting.Normally, if something is in the least bit critical I use a grinder to clean up (take a thin surface layer off) a back gouged weld prep before welding it.  I think that's just standard industry good practice.   Even if you're gouging with a CC power source.Another "good practice" is that if a particular base metal requires pre-heat prior to welding you also pre-heat prior to gouging.Last edited by HT2-4956; 07-08-2014 at 11:33 AM.
Reply:We do it all the time DC 1000. Arcair Automatic 5/8 carbons 900 amps backgouging railroad girders full pen welded.
Reply:Originally Posted by PavinsteelmanWe do it all the time DC 1000. Arcair Automatic 5/8 carbons 900 amps backgouging railroad girders full pen welded.
Reply:Idealarc DC-1000 - CC/CVhttp://www.lincolnelectric.com/en-us...roduct=K1386-3"USMCPOP" First-born son: KIA  Iraq 1/26/05Syncrowave 250 w/ Coolmate 3Dialarc 250, Idealarc 250SP-175 +Firepower TIG 160S (gave the TA 161 STL to the son)Lincwelder AC180C (1952)Victor & Smith O/A torchesMiller spot welder
Reply:Originally Posted by OldendumIdealarc DC-1000 - CC/CVhttp://www.lincolnelectric.com/en-us...roduct=K1386-3
Reply:Originally Posted by HT2-4956Oldendum,Thanks for the link.  That's a beast of a power source.   It would be my guess though that they use it in CC mode when they gouge.   Especially with an automatic (machine) gouging set up.   It would be my guess that doing it in CV mode would probably interfere with any voltage sensing feed back used for process control.  But I don't know that for sure.
Reply:Arcair auto is cv electronic electrofeed 5/8 900 amps , looks like a milled joint . Lincoln made a DC -1500 vv subarc 1940s sub arc and gouge supply. Was 2 SAE 750 hooked together.
Reply:Well, to all who have had trouble sleeping at night. I answered my own question last week while I was messing with the rig. it happens to be a 600 amp cv only machine.....  We have it set at 40 volts for all the carbons we use ranging from 3/16-1/2in.The gouges in the right hands are excellent, very smooth and controllable. In hind sight, gouging on cv makes perfect sense, to maintain arc length and all. There was a job we had to do rework on, had to cut off 2 in base plates off some beams, due to the design that entailed digging 1-1/2 in into the base plate to avoid parts that could not be scrapped. I could pretty much bury the carbon as deep and fast as I liked ( which I liked very much...)  and was like a knife through butter.
Reply:I read that for larger carbons over a certain amperage range(can't remember, 400 maybe?) that CV works better because there is nothing to limit the amperage other the maximum of the machine. Gouging should always be cleaned up with a grinder.
Reply:Arc gouging in CV is amazing. In CC the voltage will spike blowing a divot, with CV you mine layers out as even as you can hold your hand.  I think this is the secret of Lincoln Vantage's arc gouge mode.Constant Current Weldor.
Reply:Originally Posted by Joedan I heard there are concerns when gouging on cv, something to do with the amps spiking and embedding bits of the carbon electrode into the work?