Carbon arc gouging/cutting.

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I just got a screamin deal on an Arcair K3000 torch on ebay. Never used one. I am hoping to get some tips and tricks info. Especially from David R. Thanks"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:is that the stinger with the air compressor line hooked to it....?    that is the LOUDEST , COOLEST , DEEP Metal Gouging practice  i've ever seen and heard.  Man , i mean it just turns heads and demands attention when others r around . Dont u have to have like a 500Amp machine though.?        thermal arc 252i  -  millermatic 350P -   miller XMT, cp300ts, 30a 22a feeders, buttload of other millers, handfull of lincolns, couple of esabs  -   Hypertherm 1250 G3
Reply:Your Shopmaster will handle 3/16 carbons with no problem but make shore you have a lot of air compresser.I run in the 299-230A range and 60-80# on the air(did I say you need a LOT of air?)                                Bill
Reply:I should also add the a GOOD FIRE WATCH IS NEEDED                   Bill
Reply:It's like anti-welding! I love running those things! woi2ld is right, they do demand respect. Every time I had to run it, all the other guys in the shop would come by to check it out. Like "the hat" said, have a good fire watch. And wear thick clothing or layers. I've seen people get sun burn through their clothes from these things.
Reply:Leathers are your friend if you arc gouge. It's not that great for cutting but it rocks for unwelding.Tough as nails and damn near as smart
Reply:I have a 5hp 80gal comp and if that doesnt keep up I will fire up the IR 175cfm tow behind diesel, I know that will work.Push, drag, angle, depth control amps or pressure, arc or contact, ect. I did not think of a fire watch buddy, thanks. Basically I know NOTHING when it comes to this. I saw David R's bucket post, I liked the results and I found a deal I couldn't refuse.Sorry wrong forum, I meant to put it in cutting."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:Push it.Tough as nails and damn near as smart
Reply:Push it. keep the air under the gouging rod. Electrode posotive (at least thats what works for me), about 250 amps. Try not to take off to much at once. Better to make multiple passes than to take too much off. Once your done, if you want to re-weld the area, make sure you grind the area good. And wear a resperator or something, the smoke is harsh. Work from the top down if applicable, thats the way the metal will run. And in tight areas, watch the back of the rod, so it doesn't strike arc on some thing. You only want a few inches of rod sticking out of the front at a time, otherwise the air wont push the metal away. Have fun!
Reply:Torch positioned so that air jet has best possible blow-away of molten metal; that's usually with the jets closest to the work. Preserve torch head by avoiding blow-back and not using carbon down to a short stub. Flying hot molten metal will seek out and destroy cable-hose and air hoses which are not carefully positioned.It's okay to clamp the carbon anywhere in its length, to allow best access to the work.Try not to keep carbon positioned "too flat" so that it does not tend to burn away to an excessively long point.For gouging, push from a high angle with a side to side washing.Good LuckLast edited by denrep; 02-12-2010 at 10:10 PM.
Reply:you want to clamp the carbon about 4-5 inches from the end.  The carbon has a black end that resembles an electrode.  the black end is the working end.  As the carbon is consumed you will need to read adjust the carbon.  The air holes need to be on the bottom of the carbon.  The you will push the carbon at roughly 45 degrees and the metal will simply melt and the air stream will blow it out of the path of the carbon.  take it easy and don't rush, the carbon will do the work for you.  You can use it for weld removal, back gouging a weld for complete penetration, washing bolts, etc.  it is great for any thing that you need to remove metal.  You can remove the molten metal debris and start welding without further prep.
Reply:Hello Stick-man, the majority of items have been covered for you. I might only like to add a few additional topics for your consideration. Carbon arcs can be a bit hard on power sources, particularly smaller inverters, they can also be hard on machines that are tig-capable, for whatever reason, many folks have noticed performance issues after carbon-arcing if they go to use their machines to do any sort of precision tig work afterwards. A good size engine drive, 400 amps+, or an older transformer/rectifier machine of similar amperage is best suited for carbon arc work, the lighter duty high speed, air-cooled engine drives are not generally the best choice, especially if you have a lot of arcing to do. Main reason for shying away from using the smaller inverters is their inherent light-weight design, they use a lot of aluminum in their internals and aren't able to handle the type of heat that carbon arcing produces within the machine, the light-weight engine drives are classed similarly, I also believe that the "pulsing" that occurs during much of the carbon arc process contributes to being hard on the inverters or any machine for that matter, you are going from 0 to the high amp draws on and off at varying rates and somewhat shock loading the machine. Carbon rods are available from 5/32" on up to at least 5/8" diameter(roughly 160amps to 1500amps), they are also available in flat shapes, the flats are generally used for flushing applications and the rounds are generally used for weld bead removal, opening up cracks for repair work, and the other types of applications that the others have already mentioned. If you are using an auto-darkening hood while using this equipment and it has the capability to adjust the delay, you will probably want to adjust so that it is on a long delay mode, otherwise you may experience "flashing" when the arc initiates erradically due to an uneven contact with the material being arced. Have fun with your new tool, it can be an invaluable addition to your toolbox. A bit more for your consideration. Best regars, Allanaevald
Reply:A constant, smooth arc is what to shoot for. As with all welding, plan your manuevers a bit beforehand, and know what to expect. Attached ImagesCity 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:Hello again Stick-man, here's a night shot of a bit of air-arcing. 5/16" rod @ around 350 to 400 amps. We use a reliable old Lincoln DC-600 for just this purpose. Best regards, Allan Attached Imagesaevald
Reply:The "welders eraser". I used one once I doubled my ear protection.Dave ReberWadsworth Ohio
Reply:Here is a great file from Arcair with info about Carbon Arc gouging.http://www.thermadyne.com/arcair_pdfs/89_250_008.pdfI too am interested in learning more about this. I am doing a job right now that would be going twice as fast if I had an gouging setup.http://all-a-cart.comWelding Cart Kits and accessories
Reply:Just bought an air compressor and I am about to order a K2000 'light duty' torch for myself.  That K3000 you bought will demand 80PSI and 21 CFM, so you'll probably be firing up that tow-behind diesel air compressor.All the advice you've gotten so far seems sensible to me.  Plan on setting up a backstop with a fireproof blanket, or working in a wide open space.  The torch will easily throw molten metal 40-50 feet unless you block it.  This can start fires in the blink of an eye and far, far away from where you're working.ZTFab's link is great, I've got the hardcopy version from my LWS.  Pay close attention to the amperage requirements for the various size carbons.  1/8" carbon rods only require 60-90 amps DC+.  I would agree that the larger carbon rods are hard on power supplies.  I've seen big industrial engine drives rock and roll when running big carbon rods.  The current load demand at the start of gouging will literally rock the engine drive as the engine torque tries to maintain the generator rotation speed.Not sure what you have in mind for work with that K3000 torch, but it would be overkill for anything but foundry work, in my experience....Benson's Mobile Welding - Dayton, OH metro area - AWS Certified Welding Inspector
Reply:When someone mentioned current settings, I was going to say that it seems like it's always the same -  MAX. Large generator-type welders seem to be best suited for carbon burning.As  A_DAB_will_do mentioned, yes they will balk about carbon work, and may even try to walk off the job. This was a small carbon gouging job, chasing cracks. The grooves were deliberately kept narrow, so as not to remove excess material while following a crack to determine its extent. Any other burning process will usually not leave a groove so narrow and a crack so easily distinguishable.Attachment 46052Attachment 46053Attachment 46054But carbons have uses other than just gouging.Using only a carbon, this large rod was quickly heated hot enough to bend with just pliers:Attachment 46055Last edited by denrep; 10-19-2010 at 11:43 PM.
Reply:Air arcing is mucho fun!Especially like others said, it really demands respect.I have a K3000 I was planning on running off a TB 302, but finding a compressor to power it prooves hard in the sub 1k price range. Or even under 2k really...I do it at work quite often to fix mistakes people make... :]Definiately very quick at removing tons of material.Have to be careful if working near something that can get damaged (in my case, typically a flange w/ raised face or a bellow)Auto darkening helps quite a bit, to make sure you strike your arc in the correct spot, and not some random spot on the work piece that will have to get filled later ;pSeen people do that quite a bit.Keep your face pretty far away, for smoke reasons, and if you look in the miller thread about a helmet that's seen better days... that's another good reason why!nuked my miller elite by gouging in a cavity weld trying to see it ;d
Reply:Re-skinning a small dozer blade.   Note cutting out the weld, in the second picture, down to the depth of the fusion line.   I don't recall, this was a few years ago, but probably done with a Commander 500, either 3/8" carbons or 1/4" carbons.Using an air-carbon gouging torch, even thru the hood, you can find and follow the fusion line better than with any other process, including oxy-acetylene scarfing tip or grinding.  It wasn't particularly critical here, I went perhaps a sixteenth or an eighth deeper than I needed to; but even there, saved on grinding time.Again, this is old history, I'm not digging up old invoices, but due in a large part to the gouging, total hours on this job was less than 8 hours, both cutting off old skin, and installing new skin on this blade. Attached Images
Reply:I must be using it DCEN, as I always use about 225amps for 1/4", or 300 for 3/8".  I'll check on Monday, we've got a dedicated machine for gouging, I've never had to set up the torch on it, just grab and go.  I generally start with 1/3 to 1/2 of the carbon sticking out the working end of the torch.  I typically gouge with as smooth of a movement as possible, no weaving as I usually have to weld over the gouged area.  The smoother the gouging, the less grinding for weld prep.  A smooth even sound during gouging is a good indication.  If you leave a carbon deposit over the gouged area, you need to grind or chip it away before continuing to gouge, or trying to weld over the area.  It will look like a crusty coating that just won't blow away if you try to gouge over it.
Reply:If you are using it DCEN, the carbon will develop a needle-point, over a six inch stickout.   I do this occasionally, both gouge this way, and also prepare my carbon this way, on a piece of scrap, if I want or need a very precise cut.    Not normal, generally I turn the machine up correctly, and jump into it.   1/4" rod, approx 300-350 amps or so, 3/8" rod, 500 amps plus, DCEP.   In either case, air to match.   Change the air outputs, to fit the air you have available.  Two, three, four, or five holes, depending.Last edited by jsfab; 02-13-2010 at 04:45 PM.
Reply:Originally Posted by jsfabIf you are using it DCEN, the carbon will develop a needle-point, over a six inch stickout.   I do this occasionally, both gouge this way, and also prepare my carbon this way, on a piece of scrap, if I want or need a very precise cut.    Not normal, generally I turn the machine up correctly, and jump into it.   1/4" rod, approx 300-350 amps or so, 3/8" rod, 500 amps plus, DCEP.   In either case, air to match.   Change the air outputs, to fit the air you have available.  Two, three, four, or five holes, depending.
Reply:I've got a twin carbon arc torch at home I've used for heating. Usually only drag it out now if the O/A setup is emty. I have an old welding manual that depicts a guy cutting with a carbon rod with a regular stinger. Just kinda melt the material then push it out of the way with the rod. Not as nice as having a dedicated arc gouging torch, but it works in a pinch. Haven't tried it myself.
Reply:after learning about arcair in this thread i went and talked to a friend about it. he reaches up on a shelf and says here, you can have one for $50. score! i look it up online, and it is rated for up to 1/2 inch carbon rods and 1000 amps. thats a lot of power.Dynasty 200DXPassport plus w/ spoolmate 100victor 315c oxy/(act and prop)Miller digital elitemilwaukee power toolsOriginally Posted by turkafter learning about arcair in this thread i went and talked to a friend about it. he reaches up on a shelf and says here, you can have one for $50. score! i look it up online, and it is rated for up to 1/2 inch carbon rods and 1000 amps. thats a lot of power.
Reply:We had an auto carbon arc machine at a vessel shop I use to work in, we didn't use it very often but when we did it was cool. it would use rods up to 3/4 and we would run it at ~600 amps. the head was mounted to the sub arc positioning boom and it would rip down the length of a 10' seem in ~5 min. it would also throw metal 20' past the cut. It was actually much quieter than doing it by hand because it wouldn't chatter so it was a smoother noise that sounded like a 5/8" air house that was gushing air. sorry I never got any pictures of it running though.
Reply:We use a y to hook ours up on the job meaning we slave 2 welders together to get the ampage we need without destroying the welders.You can defiantly tell a difference on the machine after you gouge with it a couple of times they just dont seem to weld the same.They make awesome tools when used right but can be your worse nightmare in the hands of a rookie.After the arc has died the weld remains
Reply:Originally Posted by Boilermaker237We use a y to hook ours up on the job meaning we slave 2 welders together to get the ampage we need without destroying the welders.You can defiantly tell a difference on the machine after you gouge with it a couple of times they just dont seem to weld the same.They make awesome tools when used right but can be your worse nightmare in the hands of a rookie.
Reply:This is a job that required a little carbon gouging of cracks. Hope Stick-man doesn't mind hitchhikers on his thread.This was the dial-in test, performed  on a very rusty and scaly piece of scrap.Attachment 49410Just a dress rehearsal.This is Ye ol' Carbon Master:Attachment 49409GE motor-generator.Carbon Master is very powerful, and  inspired a phrase that previously had never been heard while carbon gouging: "Turn that noisy &^%* down." This was the main event:Attachment 49408With all cameras rolling.Last edited by denrep; 10-19-2010 at 11:44 PM.
Reply:Carbon arc and dual shield wire feed were made for eachother.  When welding inserts in plate, simply weld from one side, gouge the reverse side, and weld back in the other side.  This is a very common practice in shipyards and surely beats beveling plates prior to welding.Another note about carbon arc is that it will gouge cast iron and stainless.  The torch wont touch the stuff.
Reply:I don't mind at all. Very cool stuff you're doing there. I especially like the photography and your "special effects".What size carbons, 1/4"?"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"