What to use in a Carbon arc torch?

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Yes, I recently picked up a 'carbon arc torch'  at a garage sale.  AFTER TRYING    'arc air' rods in the torch, and having what I would consider poor results, I am now  wondering  what rods to use, my supply man says he doesn't know either, he has never had anyone besides me inquire  about rods for such a tool, and he has never seen one or knew of there existence! Has any of you suggestions, or know what rods or rod will work best?
Reply:Did you hook the air arc up to the welder and plug in the air? amperage set to cut? air pressure correct? hot lead hooked to the air arc? ground hooked up to piece being cut? thats all i got one more thing air should be comming off the bottom or under the air arc rod.Last edited by B2N3 Welder; 09-12-2006 at 03:10 AM.
Reply:The kind he's describing sounds like the kind that forms the arc between two carbons, not between a single carbon and the weldment, like a CAC-A torch.Like the ones in this thread: http://www.weldingweb.com/vbb/showthread.php?t=4090
Reply:Lincoln still makes an arc torch. I've had one for many years. I run it from my antique Trindle AC Buzz box welder. The Lincoln number for their arc torch is K1876-1. The electrodes come on two sizes: 1/4" (KP1905-1) or 5/16" (KP1905-2). The electrodes must have a copper-plated exterior to work. Sears used to sell the torches under their own Craftsman brand and they used to sell the electrodes. Most welding products dealers will have the electrodes. An arc torch does wonderful brazing and silver soldering and is far less expensive than oxy-acetylene.
Reply:gnm109 and Mac702 are correct, I am speaking about a two carbon rod , arc torch, there is no air attached.Besides the rods from Lincoln,  are there any other ideas / or sources for rods ?I think this tool needs solid carbon rods to work well, do you agree? But who has them?
Reply:I described a couple of successful applications of a single carbon "burner" in a couple of posts in the thread that MAC702 mentioned.As I stated there, I think that the carbon "torch" has some very useful applications, but it is certainly not a general purpose tool.  From the discussion here and in the other thread, I believe that most of the problems guys have described is that they do not have adequate control over the current and they are using the tool in the arc mode, rather than in the contact mode.If we speculate that the arc might have a voltage of about 25 volts and the current is, perhaps, 40 amps for a typical buzz box on low range, that's 1 kilowatt of power in the arc.  From what everybody reports, that will melt through sheet metal in a hurry.On the other hand, if you maintain hard contact of the carbon with the work, there will be very little voltage but. let's speculate, still 40 amps (depending on the volt/amp curve of the specific welder).  Let's say there is a voltage drop of two or three volts along the length of the carbon.  That's about 80 or 120 watts.  Actually, most of the power will be concentrated at the point of contact with the work due to the contact resistance.  And, of course, the contact resistance is subject to control by operator technique.My conclusion (and my experience) is that a single-carbon holder is quite useful for some specialized tasks in which you want to concentrate heat at a point of contact between a carbon and a workpiece, but is definitely not a general-purpose replacement for more conventional welding techniques.  My single-carbon torch with a 880-watt very low voltage, high current transformer has been very useful in the contact mode.  Try it out.Regarding carbon availability:  I hunt and gather  at surplus joints in the Los Angeles area a few times a year on family visits and I'm pretty sure that I have seen carbons there.  Didn't buy any because my carbon holder takes a stubby, large diameter carbon, not the copper-coated arc lamp carbons surplussed down there.  My guess is that they came out of the movie industry.Many of the surplus places are so disorganized that they might not even know what they have, but it's worth a try.  Two good possibilities are:Norton Sales, Inc. 7429 Laurel Canyon Blvd. North Hollywood, CA 91605 Phone: 818-765-1087, 800-946-6786 (toll free)Fax: 818-765-8969 http://www.nortonsalesinc.com APEX ELECTRONICS8909 San Fernando Rd.Sun Valley, CA, 91352Tel: (818) 767-7202. Fax: (818) 767-1341. Web: http://www.apexelectronic.com ...www.apexelectronic.com Email: [email protected]
Reply:I think Forney may still make them too. I have a box of carbons for mine, but haven't used it since I got Oxy-ace. What make is the torch?
Reply:As I informed Flywelder in a private message...In my carbon arc set up, described in another post, I went to two welding suppliers (BOC and Air Liquide) and both carried carbon electrodes. It is possible, that if you walked in there and spoke about twin carbon arc torch, you may have confused them (duh?); just ask for carbon electrodes for 'arc gouging' - that they understand!  Boxes of carbon electrodes are on the shelf!Both welding supply stores had carbon electrodes available in 12 and 14 inch lengths from about 3/16 inch diameter up to 5/8th inch, in plain carbon or copper coated, in paks of 50 or 100. I bought 3/16 x 12 inch copper clad - made by ARCAIR (Thermadyne), 50 in a pak for about $14 US. I could have done better on price - more like 100 pak for $18.My 3/16 electrodes burn up quickly (typically 30 seconds max burn before I have to adjust the gap between the rod tips) when running about 60 amps AC through them.  Note: I typically break a 12 inch rod into two 6 inch lengths and use the short lengths in my holder.  The 6 inch lengths lasts quite a while - several small jobs.  My 117 VAC welder can go as high as 85 amps AC but the arc is more intense than I need and the rods go quickly (15 seconds - then the arc goes out as the gap becomes too large for the arc to jump).  If I had to do it again, I would likely go for somewhat larger diameter rods say 1/4 inch to get a longer burn time. You don't want to go too big else you need a lot of amps to power the larger diameter rods.Anyway, carbon electrodes (for arc gouging) are standard fair in the welding shops here.Drill With Carbon ArcI have used a single carbon electrode to drill (burn) holes in very tough 1/4 inch plate - that liked to eat drill bits!  If you try this, the problem is creating the arc - between one carbon rod and the work piece; it just doesn't want to happen.  The trick is to soak a regular welding rod in water, then try burning the hole with that.  It may not work but ... it leaves behind a mound of weld covered by slag - that slag residue contains the chemicals that will maintain your carbon arc!  Change from the wet-welding rod to the carbon rod and - presto - instant arc to (drill) burn your hole with - at the right moment, just push it right on through the base metal.Rick V